Relatedly, there is evidence that certain types of "resistant starch" can help reduce visceral fat. This starch comes from green bananas, potatoes, legumes, etc. It has to be either raw (there are supplements for this) or cooked and cooled.
"Resistant starch intake facilitates weight loss in humans by reshaping the gut microbiota"
sample size n=37 of which recruitment only happened in Shanghai without any real control for confounders, only evaluated over a period of two weeks with no longterm follow-ups, the dosage of 40g RS/d is very high (would take about 4-5 large potatoes daily for equivalency or ingesting likely expensive supplement), the crossover compares RS vs CS in the same participants with only a 4 week washout which is a weakness since fermentable fiber persists >4 weeks, also the supplement they used was industry-provided by a starch manufacturer which was weirdly not disclosed
this is a great study if you are an overweight/obese adult without overt metabolic disease, willing and able to consume 90 g/d of starch supplement within a controlled diet, and living in Shanghai with similar baseline fiber intakes endemic to that population. it is extremely not generalizeable to you or even me though I fit more of those characteristics than I care to admit
Also, the authors claim the starch "inhibited lipid absorption." They do not argue why they used surrogate blood biomarkers instead of residual energy output in fecal samples (which is a better measurement).
You can just go on a calorie deficit and it will reduce your visceral fat when you start getting lean enough.
But obviously, most people are a lot more interested in finding a magic food which does this rather than a proven calorie deficit, which is highly effective.
Purely behavioral lifestyle interventions have the lowest long term success rates of all available treatments for obesity. It's especially unreliable if you have weight loss targets higher than 15%.
They are of course still widely recommended due to numerous benefits other than weight loss, but "highly effective" is just wrong in the context of obesity treatments.
> Purely behavioral lifestyle interventions have the lowest long term success rates of all available treatments for obesity.
What? Surely changing one's behaviour - particularly the parts of behaviour that caused the obesity in the first place - is a sure way to stop being obese.
To do it right it requires quite an effort to no go too much into calorie deficit.
It definitely is not "you can just go on a calorie deficit", that is how jo-jo effect works.
For average person that has children, full time job, and whole range of adult responsibilities it is hard. Not impossible but hard, this is why people are looking fo easier solutions.
Why not, though? Eating is fun and pleasurable. If we can figure out a way to eat the things that we want, in the quantities that we want, while maintaining our health, why shouldn't we try?
I've lost weight through forcing myself into a calorie deficit, and it works really well, but it's not particularly fun.
Abstention is commercially a no go zone, eating 'different' is a goldmine. It is why 'going on a diet' in the 1970's still meant eating less, while starting in the 1980's the phrase was turned into just eating the latest industry fad miracle food.
You can induce a calorie deficit by eating foods that fill you up but don’t have many calories. Also avoiding the sugar-spike carbs cause leaving you even hungrier shortly after works also.
A good dietician is worth a few consults if you don’t have the will power to just fast. And as a bonus you don’t lose muscle mass as well because they’ll focus on keeping protein up.
>A good dietician is worth a few consults if you don’t have the will power to just fast. And as a bonus you don’t lose muscle mass as well because they’ll focus on keeping protein up.
Fasting is like using a nuke where a bullet would do.
How will a dietician measure your maintenance calories? How will they continuously update your macros and calories when your maintenance calorie change week to week?
I am making a claim here: most dietician will not be able to track your maintenance calories better than MacroCodex's algorithm.
Many dieticians simply rely on BMR/TDEE static formulas, and the limitation of this approach is that it cannot reliably track a user's actual maintenance calories well through the span of their dieting journey.
The vast majority of people who lose weight by calorie restriction gain it back, so I wouldn't call it highly effective. Short term yes, but long term, definitely not.
How are you defining highly effective? In the sense that a body will definitely lose weight when starved? Or in the sense that counting calories is broadly effective as a weight loss strategy?
The former is painfully obvious and entirely unhelpful, and the latter is provably false.
Counting macros is extremely effective. The general population doesn't have the discipline for it, but amoung sport coaches, actors, models, bodybuilders, this is *the* technique for achieving goals.
Anyway what's cute about this is that this isn't novel phenomenon. There are lots of parallels to this in other fields where often effective solutions do exist, but at a system level don't seem to work.
Telling people to diet doesn't fix population level obesity. Telling people about personal financial management doesn't stop people from accruing too much high interest debt. Telling teenagers to stop idolizing instagram influences doesn't fix body anxiety issues. Telling people to stop smoking/drinking doesn't fix addictions. 3-2-1 data backups absolutely work but people lose files all the time.
>In the sense that a body will definitely lose weight when starved?
If your maintenance calories are 2700kcal and you eat 300kcal less than that, is eating 2400kcal starving for you?
Most people cannot tell a difference if they eat 100-150kcal less in a day.
>Or in the sense that counting calories is broadly effective as a weight loss strategy?
Yes, it is, and the reason people fail with it is not because calorie counting doesn't work, but because people's maintenance calorie estimates are often poor.
calorie restriction can cause a reduction in resting metabolic rate through "metabolic adaptation". that is, your body gets used to the deficit (by shedding metabolically active tissue and other things*) and burns less calories at rest. so, paradoxically, restricting or reducing your caloric intake can have no effect whatsoever on your weight.
The problem is: average person is bad at counting calories. They overestimate number of calories burnt, and severely underestimate number of calories consumed. Once you get your math right and get into real, not imaginary calorie deficit you'll start losing weight. Rule of thumb: whatever you think the amount of calories is in your current meal, double your estimate.
Mark Stache ( https://youtu.be/L-gNdQZorEE?si=nkwAhZOiAFtY2f44 ) just did a 90 day evaluation. The biggest problem at the level they mention is some intense flatulence. He is also in good shape and had mixed results compared to the study.
IMO my only concern is their dats shows they were actually able to maintain a pretty controlled diet for each participant, I wonder how selection was done. I also would've appreciated some bomb calorimetry of fecal samples, similar to [0] which is the widely cited paper that does link general fiber intake to a lower level of caloric/energy absorption.
Baer, David J., et al. "Dietary fiber decreases the metabolizable energy content and nutrient digestibility of mixed diets fed to humans." The Journal of nutrition 127.4 (1997): 579-586.
I seriously don’t understand why you people need to optimize every damn thing. Eat real food and take a walk for maybe an hour a day. Within a year you will have lost a lot of weight. Stop inventing new terms and just eat reasonably instead of eating like pigs FFS.
> The study was conducted in Shanghai, China from 3 July 2013 to 14 October 2016
Figuring out and understanding the physiology of different gut bacteria is not just for people trying to shortcut weight loss while still eating unhealthy food or to be sedentary all day.
Eh, the "real food" of Jamie Oliver and Michael Pollan (shop the peripheries) and such isn't very health promoting. So I'll pass and keep eating a mix of fresh food and cheap food that keeps for a long time like legumes. Kthxbai.
To Michael Pollan it seems they aren't worth mentioning right in the first breath when talking about real food, but perhaps an afterthought. "Shop the peripheries" causes them to be lumped in with potato chips and oreos and other stuff that aren't in the peripheries of a supermarket. I don't accept the same real food dichotomy that they do.
For non-invasive heart disease risk prediction nothing beat ECG, period.
Somehow American Heart Association and its European counterpart are in denial, and still pushing dinasour screening mechanism with very low accuracy for heart disease risk prediction.
The standard risk model for CVD based on PREVENT (US) and SCORE-2 (Europe) like parameters are very poor as reported in the recently published paper on the their accuracy performance by the Swedish team [1]. As all CVD risk stratification with cardiologist review (expert-in-the-loop), the most important accuracy metric is sensivity/recall (avoiding false negative that will escape review) of PREVENT and SCORE-2, 26% and 48%, respectively.
The paper alternative proposal increased the sensitivity to 58% by performing clustering instead of conventional regression models as practiced in the PREVENT and SCORE-2.
These type of models including the latest proposal performed very poorly as indicated by their otherwise excellent and intuitive display of graphical abstract results [1].
[1] Risk stratification for cardiovascular disease: a comparative analysis of cluster analysis and traditional prediction models:
I'm not sure how ECG relates, how would ECG predict heart disease risk? I don't see any evidence of that, it's not even mentioned in the article you linked, which is odd considering the whole approach of clustering is gathering as many risk factors and relevant test results as are available.
There are lots of different types of heart disease. An ECG can be useful for diagnosing some of them but you're overstating the relative value. For many patients, a CT coronary calcium score or CT angiogram may be more valuable in terms of detecting the type of arterial plaques that might require medical management or major lifestyle modifications in order to prevent a heart attack. These are also non-invasive, although they do involve some radiation exposure.
Having a CAC done is fairly cheap, ~$100 in the US. Insurance typically doesn’t cover it, but if anyone is concerned, it’s worth calling to set one up.
My dad’s doctor said he should get one, Medicare denied it, but he paid out of pocket to get one anyway. He found out he was 95% blocked pretty much everywhere and had a quadruple bypass. It likely added many years to his life and avoided a heart attack.
If you’re under a certain age (I want to say somewhere in your 50s), there isn’t any guidance for what normal is. If you’re in your 20s or 30s, I wouldn’t run out and get one. But if you’re in your 40s with a family history, or up into your 50s and beyond, it’s worth thinking about. I’ve also heard you’re only supposed to get them every 2-3 years, it’s not a yearly thing, due to the radiation.
It was just added to the recommended screenings list and my doctor expects that insurance will cover it soon because of that. Still at under $100, it was well worth knowing that i don't need aggressive treatment. (Though a quadruple bypass beats a heart attack)
Then again, CAC measures end-stage calcified plaque, not the soft plaque it started as, equally clogged arteries but also able to break off to cause strokes until the body calcified it.
The time to take action is long before you have a CAC score. e.g. Start tracking ApoB regularly, see if you have genetic LPa exposure, and avoid the foods that increase your exposure while ignoring the grifters telling you it's a nonissue.
Emphasis on non-invasive diagnostic screening as invasive testing like angiogram need to be operated by specialist and can take months to be arranged, and only done after incidents e.g heart attack.
ECG is excellent for generic top level CVD anomaly conditions for examples arrhythmia and ischemia.
Huh? I get a blood panel every year and 90% of the things it looks for are normal year after year. But there is always 1 or 2 things flagged that I need to pay attention to.
An ECG if it was just part of the normal yearly panel of things that get looked at I don't think ppl will stop doing it just because it doesn't find something right away
Nobody said anything is worse. Half this thread is satire. But on a serious note. ECG is really time prohibitive, drawing 3ml of blood is relatively quick, and doesn't require specialist training like an ECG does.
Get as many scans you can under insurance. Data is king and Claude happens to chew it all pretty well. Apple Health data by itself and family history is enough to make a starter PDF for your cardiologist.
Getting an ECG, EKG, TTE, CAC, carotid duplex US, lipid panel, CMP, TSH, 25-OH Vit D, B12 + folate were what my cardio recommended before appointment #2 on hypertension. Both of us are data guys.
You don't even necessarily need insurance. Some of those tests you listed are pretty cheap so most people reading this can afford to pay out of pocket even if they're not covered by insurance.
I thought this was pretty well known already. Being “overfat” is the problem, not being overweight (though they’re often correlated). BMI is really easy to measure, and is mostly accurate, that’s why it’s so pervasive. However it remains a pretty rudimentary metric (and really should use the third power or your height instead of the second).
> BMI is really easy to measure, and is mostly accurate, that’s why it’s so pervasive.
BMI is easily misunderstood by people who know just enough to see that it’s imperfect, but not enough to understand why it’s still a valuable screening tool.
I’ve been in the “overweight” BMI range with low body fat before. It’s not too hard to get there if you’re lifting weights and paying attention to your diet consistently for years, but it takes a lot of work to get there. It doesn’t happen accidentally except for people who win some genetic lottery to build a lot of muscle and keep body fat low without trying.
Getting all the way to the obese BMI range while having healthy body fat is only happening for people with an extreme dedication to body building and diet (and let’s be honest, a lot of the people in this category are manipulating hormones too).
Yet whenever BMI comes up some people try to dismiss it as too flawed based on these possible edge cases. The edge cases for BMI exist, but that doesn’t mean it’s not useful. It’s a good general purpose screening tool with numbers that are available. If someone has more precise measurements available, those should be used instead. BMI is a really good first pass screener to determine if a closer look should happen.
At a population level, it's great. For individuals, it can fail in all kinds of ways. For me: it is not very good because my body has very strange proportions. I'm 6'2", but my waist is barely higher than my 5'1" wife, and my torso is nearly the same length as my 6'7" brother.
In other words, for my height, I have a very long torso and very short legs. I think it should be relatively obvious that an inch of leg weighs significantly less than an inch of torso, so at a given level of body fat percentage, I'm going to weigh quite a bit more than someone my same height with more typical proportions, and thus my BMI reads me as more overweight than it otherwise would.
My point is not that BMI is bad or useless or anything else. My point is that it was designed as a population statistic and that it can be fraught when one tries to apply it to any individual with no nuance. A high BMI should cause one to consider and examine your health and weight. But it should not over-ride specific details about your physiology that point in the other direction.
> I’ve been in the “overweight” BMI range with low body fat before. It’s not too hard to get there
Did you do that as a natural lifter? It’s hard for me to imagine most guys being able to get into the “overweight” range at < 15% body fat without some assistance.
The farther from average height you are the worse it is. If you are from some part of the world where the average height distribution is near the point BMI based itself you will perceive it to be so much better.
I am only 6' and only an intermediate lifter. I'm overweight, but BMI makes me look obese. It really only takes a normal person a year or so to get to three plates on squat with no supplements other than chicken broccoli and rice if they don't skip workouts. Assuming no injuries. That level of strength easily distorts bmi wildly if you are even a little taller than average.
Yeah, people don't want to understand that your body structure messing with BMI is quite real but only a few points. It's unquestionably "wrong" in scoring me higher than my wife despite the fact that she's the one with a few extra pounds. But it scores us both as normal, the difference doesn't matter.
>Getting all the way to the obese BMI range while having healthy body fat is only happening for people with an extreme dedication to body building and diet
And sumo wrestlers.
The line seems to be drawn at (effortful) activity level more than anything else. And BMI doesn't say anything about that.
I think the vexation comes from the focus on an attribute that is not directly mutable, per one's agency, because that's easier to sell things related to. Versus action that you have a lot more direct control over (social or physical circumstances notwithstanding).
Yes, it is a pretty high level metric with good correlation a bunch of diseases, but really many of these is because it is ALSO correlated to percent of fat, which is often the more relevant metric. But as you said BMI is so much simpler to measure.
Many active gym people have pretty high BMIs but fairly low fat (because muscle is dense), and unsurprisingly have better outcomes than the average person (if you ignore the share that uses/overuses anabolic steroids and co)
> Many active gym people have pretty high BMIs but fairly low fat
I think this is greatly exhaggerated.
Yeah you can put on as much muscle as Arnold and have a FFMI of about 27 then maybe have a BMI of 34 if you have 20% body fat.
But a very gifted natty might cap out at maybe 24 with a BMI of 30 at 20% bodyfat. But let's be realistic. This is not "many active gym people". This is the guy winning the local strongman meet.
Yes a couple of years training for most people can add a couple of points to BMI but I think people exaggerate how much this is. Go look at a 20lb brisket at costco - you don't see people with that much extra muscle all that often.
I do agree to some extent, but really the overweight threshold for BMI is 25. And 30 for obese.
At 6 feet / 183 cm that it takes 184 lbs / 83 kg to be overweight. From what I could find, for regular gymgoers the typical weight for people around 6feet is 180-190lbs, which put many people around the overweight threshold. I am myself at 24.9, and while not skinny I am definitely in the skinnier half of the people at my local gym.
My completely made up rule is you get an extra point for every plate you bench (or squat etc). Its not a dramatic difference. If you bench 225 you’re not overwreight till 27 BMI, which iirc used to be the actual cutoff until they narrowed it.
Obese is hard. Overweight is easy if you walk, take the stairs, do the occasional pushup, and play something like hockey once week. Source: my entire life.
But specifically, it requires no gym time. Muscle mass is built with through reps not weight, and there are lots of non-gym-rat behaviors that do that. I'm not winning any comps.
> Many active gym people have pretty high BMIs but fairly low fat (because muscle is dense),
I’ve been in the overweight BMI category with low body fat by being active at the gym and focusing on diet. It takes some work to get there.
If I check the calculators for the obese BMI range, there was no way I could get there without either gaining a lot of fat on top of the muscle. The amount of muscle required to have an obese BMI with healthy amount of fat is absurd.
Not sure I follow the logic here, but happy to be proven wrong if I'm misunderstanding. It's not intuitive to me that a 300 lb. person at 20% body fat is generally at the same risk as a 200 lb. person at 30% body fat.
Fat is inherently unhealthy for you beyond some low baseline level.
Additional muscle is positive for health, but only up to some reasonable threshold. There is no health benefit to having very high levels of muscle, and in fact it may be negative for your health at extreme levels. E.g. many bodybuilders have trouble breathing, sleep apnea etc.
Both people in the example have 60lbs of fat. 1lb of muscle doesn't cancel out the negative health effect of 1lb of fat
Looking for some references on these claims, thanks! What you're saying registers as "makes some sense, but where's the evidence?" to me. I'm not seeing the connection where total lbs of fat is inherently worse than higher percentage.
The mean height for men at 20-29 is 69.2" and 80+ is 67.1" (measured in 2015-2018, the last data I've found) [1], which could be interpreted as shorter people having lower risk of all mortality. One could say that people are just getting taller over time and 80+ y.o. were shorter at their 20-29, but we also have the median height for 20-29 fro 1970s, when 2018's 80+ were 20-29 - it's actually 69.7" [2], men in the US are getting shorter over time, so unless people naturally shrink 2" with age the data points to shorter people having lower risk of death.
I am not saying that. I am saying that the theory about absolute amount of fat being bad for health, as stated by the comment you responded, seems to be supported by data.
"People typically lose almost one-half inch (about 1 centimeter) every 10 years after age 40. Height loss is even more rapid after age 70. You may lose a total of 1 to 3 inches (2.5 to 7.5 centimeters) in height as you age."
So people DO in fact tend to lose about 2 inches at age 80 versus their younger selves.
Some are more common in short people and some are more common in tall people. Hypertension is one of the ones more common in short people and is significantly more common than the rest combined, so your overall chance of having some form of heart disease goes down as you get taller. However, the forms of cardiovascular disease more common in tall people (e.g. atrial fibrillation) are more likely to actually kill you.
Do you have a citation for that? I've had thoughts in a similar direction (specifically around the upper/lower intervention points) but have had no luck finding data.
Another common misconception is that one is still healthy with high BMI that comes from having lots of muscle. It's not clear that lots of muscle is healthy.
How accurate is it, in practice, for a given individual? I'm not that out of the ordinary proportion wise. I have a slightly longer torso and arms versus my legs, a somewhat muscular-ish baseline and broad shoulders, but I accumulate fat almost exclusively abdominally. My teenage self, lifetime peak of my fitness, no visible body fat, hyperactive football player, qualified as solidly overweight. If I was to listen to it, I'd be called obese before I noticeably start to show body fat.
I often wonder far from the median I am in this regard. I was under the impression that it was pretty accurate for assessing populations, but fell apart very quickly at the individual level. How many "normal"/otherwise healthy people do fall outside BMI's numbers?
It’s a tool not the tool. If you have obese BMI you can… look in the mirror and see how accurate it is. If you aren’t sure take one of the dozens of other tests. People focus too much on it being a one stop shop - it’s not. It’s the start of a dialogue with your pcp and self on assessing your health that’s highly correlated with poor health outcomes.
I haven't been down in the normal BMI range since 8th grade. And I was measured at 6% body fat my senior year in high school! BMI has always run several points high for me. For that reason, I've always liked waist to height ratio better.
It's not really intended to be applied to individuals at all, but if you're in the "healthy" BMI range then you are probably fine just not thinking any further about your weight and doing something like measuring your body fat percentage would just be a waste of time and a source of stress for some people. If you're outside that range, then it is worth doing some of the more involved things to judge if your weight is healthy.
That was my impression as well. I'm just wondering if there are actual numbers to gauge by how much. I'd find it almost concerning anyone would draw any conclusions from it if it's not significantly any better at predicting health outcomes than a coin toss.
BMI is at best 66% accurate, so "mostly" is correct, but what is mostly good enough for?
BMI has known biases in gender, age, and race. It misclassified Asians, women, elderly w sarcopenia, and people with high body fat to lean tissue ratio.
Yeah BMI is sort of a 'good enough' technique but also has some very obvious areas that it can miss. If you fall outside the typical fat to muscle ratio is a good example.
A muscular person can be "overweight" by BMI standards but not overfat at all. This is the case for many types of athletes, specially in strength disciplines but not only. It is the case in the fitness world that people ignore BMI and are intesterested in body-fat-percentage instead. This is hard to measure accurately so not so useful metric for the general population.
It's also possible to be overfat without being overweight! These "skinny fat" people often look normal enough but they carry very little muscle. It is a concerning condition because a doctor might not recommend a normal-weight person to hit the weights.
I like to think of this as four quadrants around two axes. Low fat/low muscle is simply skinny. High fat/high muscle is the "big guy/gal" look that I associate with laborers. Low fat/high muscle is an athletic look; unhealthy in extremes (bodybuilding) but generally desirable. High fat/low muscle is skinny fat, which I associate with sedentary knowledge workers.
The dominant discrepancies are "expected" fat (boobs, etc), and "unexpected" muscle (cyclists, body builders, hard labour careers, etc). I'm currently around 10-15lb overfat and 40-50lb overweight [0]. Only the former statistic matters.
[0] And that, at least somewhat, tracks visual perceptions. Nobody looks at me with a shirt on and believes I need to lose weight, because 10-15lb isn't _that_ much extra on a tall frame. If I were 40-50lb overfat then that would be painfully obvious regardless.
In my mind, it's equivalent to subtracting a coarse estimate of how much extra muscle by mass I have compared to the median adult male they're using to construct BMI charts.
My actual methodology is pretty crude though -- when I was 15lbs lighter I had borderline visible abs and other visual indicators of being around the 15-20% body fat mark, and aside from gaining weight I don't have any reason to believe I've had any notable muscular atrophy since then, so I'm estimating the actual excess fat in that ballpark. It's be easy for numbers to be off 10lb or more, but even then it'd still indicate the overfat surplus being much less than the overweight surplus.
A better methodology uses calipers and various skin measurements to estimate true body fat percentage.
I've been considered borderline or obese by the standard BMI index for 20 years at least, but for a lot of that had very little to no visible extra weight. A lot of that was just plain having more muscle than the average the standards are built around, but I also suspect BMI gets to be really inaccurate for tall people. I would look anorexic if I had to drop enough weight to be considered not overweight.
"Overweight" can mean the same thing for weight, but it also refers to those with a BMI specifically between 25 and 30, and those with BMIs greater than 30 are classified as "obese".
It's specifically a high level of visceral body fat.
Genetics determines which parts of the body gain fat first as you gain fat overall, and some people have the unfortunate genetics to gain it first viscerally and some people have the fortune to gain it there last (and everything in between).
This means that you can have different people with the same body fat percentage but drastically different disease risks.
But yes this was also known already.
That's why it's been recommended to take a waist measurement alongside BMI to get a much more informative screening tool. Waist-to-height ratios are another alternative.
A nitpick about the title: Not strictly abdominal fat, but visceral abdominal fat, which surrounds the organs. Not all abdominal fat is visceral; in fact, in many people the majority is not.
The article mentions visceral early on, which is the subject.
Seriously, you don't think there's a connection between visceral fat and abdominal fat even though there's plenty of evidence that there is along with just common sense?
It's just a particular type of abdominal fat so obviously the more abdominal fat that you can see it means you also have more of the type that can't see as well... It's not that complicated
Thirty years after we learned that abdominal fat distribution matters, large-scale longitudinal evidence shows that waist measurements meaningfully reclassify cardiovascular risk beyond BMI alone.
BMI isn’t a good metric, this has been known for a long time.
For example, I’m 45yo/178cm/93kg and am obese by BMI measurement. However, my body fat is 20% (Dexa), VO2 of 50 (lab) & have the aerobic fitness to run a half marathon after work and not care.
I’m not surprised that you need other metrics like hip/waist ratio, measured body fat, visceral fat, etc to better understand the composition of someone’s body and how it might relate to health outcomes like heart disease.
Subsequent risk of nine cardiovascular/mortality outcomes in >260,000 people followed for ~20 years
To make it even more useful they should have included DEXA scan bodyfat%.
Also, BMI becomes somewhat biased at height extremes because body mass doesn't scale exactly with height². Humans aren't geometrically scaled copies of one another and empirical scaling exponents are often somewhere between 2 and 3. Conventional BMI tends to read relatively high in very tall people and relatively low in very short people. But changing the exponent would only fix one relatively small limitation of BMI
For better height adjusted replacement for BMI itself, one option is Trefethen’s BMI
WHR and WC is positively correlated to bodyfat% but this may get distorted for strongmen or sumo wrestler who tend to have much higher than average lean mass, may also have higher WC and WHR but difference maybe waist to shoulder ratio, they tend to have much bigger and powerful shoulders.
what's interesting is, for sumo wrestlers specifically, WC still correlates strongly with BF% one study reported r ≈ 0.86
There is a category in fitness called "skinny fat" where you are at low bodyweight (so low BMI) but your fat mass is relatively higher when compared to lean mass, so higher bodyfat%
Many skinny fat people refuse to believe they carry higher bodyfat% because they think they've low bodyweight so they can't possibly carry higher fat, which is wrong.
> Those with obesity and low WC [waist circumference] were not found to be associated with a significantly different risk of outcomes compared with those who had normal weight and low WC, except for all-cause mortality, for which risk was significantly lower.
If I'm reading that right, it sounds like obesity (and therefore BMI) is still a better predictor for all-cause mortality. Perhaps waist circumference is better at predicting cardiovascular risk but BMI is still useful.
Same for me, no one considers BMI to be a good indicator of anything, but it is better than nothing, and more importantly, it is super simple.
Any idiot with a bathroom scale and a measuring tape can do it. And by adulthood, height doesn't change significantly and you probably know it, so you may not even need that measuring tape. Other metrics need specialized equipment, error prone or complex procedures, etc... I don't even know how to make a waist measurement. Where exactly? How relaxed should the subject be? How long after eating?...
That's the value of BMI: simple repeatable. Not the best but enough to get and idea and make statistics.
> And by adulthood, height doesn't change significantly and you probably know it ...
But height does change in adulthood [0]. On average people living past 40 gradually lose height. At age 80, it's likely height loss will be >=2 inches. This loss is reflected in higher BMI even when body fat content hasn't changed. Average BMI increase isn't large, but think about a person losing 4 or 5 inches of height while maintaining body fat unchanged.
Self-reported height is generally greater than measured height. Adding 1/2 to 1 inch is common (per experience measuring height). "Height inflation" has modest effect on BMI but problematic in research and workup for medical procedures. In the latter cases, measuring height is necessary.
Cutting saturated fat to under 15g per day and increasing intake of viscose fibre (e.g. beans) will reduce your LDL particle count in a few weeks, which reduces your CVD hazard ratio. You can measure your LDL and look up the papers yourself. Statins will reduce it a lot too (potentially with side effects). Replace solid fats like butter with liquid fats like olive oil.
Literally any amount of regular exercise, including walking, will decrease CVD HR. The more the better (up until quite a large amount e.g. professional athlete). The more your heart is steadily pumping during exercise the better. Every bit helps reduce CVD risk. Movement is medicine.
For the love of God do not smoke. Literally one of the surest ways to die a horrible death. Stopping smoking reduces CVD risk by a large amount.
Do not give yourself diabetes by eating vast amounts of sugar. If you are doing this, stop. Not having diabetes decreases CVD risk.
Other factors you probably can't change so focus on these.
Doctors, if I got anything wrong please correct me.
> Do not give yourself diabetes by eating vast amounts of sugar. If you are doing this, stop. Not having diabetes decreases CVD risk.
Not eating vast quantities of sugar is good advice, but it's not the direct cause of T2 diabetes. The best evidence suggests that T2 diabetes is caused by the accumulation of fat in the liver and pancreas. See the twin cycle hypothesis. To prevent diabetes, one needs to maintain a weight low enough where the body isn't storing fat in the liver and pancreas (everyone has their own individual threshold for this). If you're pre-diabetic, lose enough weight and most people will regain insulin sensitivity.
> Do not give yourself diabetes by eating vast amounts of sugar.
This can help sustain a high level of exercise (the more the better). Certainly don't if you're sedentary, but the sugar during exercise is really helpful for getting in 10+ hours/week of exercise.
I think the recent stance (not really recent in terms of assumptive idea, but now there is evidence) is that not all forms of sugar intake are equal. For instance, habitually drinking beverages with sugar in them (what are called sugar-sweetened-beverages in literature) is associated with a risk of developing T2D, where getting sugar from normal foods isn't really.
You said all this like you know something, but you didn’t bring up oxidative stress once. I mean, smoking is the leading cause for increasing oxygen stress in the body so you kind of mentioned it there but oxidative stress can be controlled with nutrients like zinc, copper, and manganese.
> Studies have shown that visceral fat, which is fat that surrounds the internal organs in the abdominal area, is associated with chronic diseases like heart disease and diabetes, while subcutaneous fat, which is located directly under the skin, is not as strongly associated.
How does one determine if one has an excess of visceral fat?
A DXA (DEXA) scan will quantify visceral fat for you. This is a non-invasive scan which uses a low-dose x-ray. Most cities have some sort of sports medicine facility where you can get one. It's typically not covered by health insurance but fairly cheap to pay out of pocket.
whats wild is there are people who look very fat - who have lots of subcutaneous fat, who don't have visceral fat. The excessive subcutaneous fat can be hard on your joints but doesn't seem to correlate to other health issues.
For two people that are the same height, one could have X lbs of pure muscle, and one could have X lbs of pure fat, and they would have the same BMI. Color me shocked that it is not always a good predictor of disease.
The irony of BMI is that people with plenty of muscle mass are more likely to have a high BMI as well as lowered risk for heart disease.
BMI was never meant to be used as a diagnostic measure. BMI is just a rough filter for large data sets, and entirely dependent on the average height and habits of that population.
Anyone taller than about 6'3" could tell you the recommended weight according to their BMI has always been absurdly low. If it's a printed chart on the wall, they might not even be on it.
BMI is not a good metric for really short and really tall people.
The "ideal weight" of a person is proportional to height to an exponent somewhere between 2 and 3. Simple physics would say 3 but because tall people are not just scaled up copies of small people, it is closer to 2 in practice, maybe around 2.3, but we say 2 because it is easier to calculate.
The downside is that BMI overestimates the "ideal weight" for short people and underestimate it for tall people. But BMI is not great at capturing exceptions anyways, so there is little interest in "fixing" this.
This is a common misconception. BMI while an ok population metric, for individual's the biggest problem with is its poor sensitivity - it fails to classify people as obese who are obese.
Using your 6 3" male as an example, they are significantly more likely to be clinically obese (using waist circumference, body fat % etc) at a weight lower than BMI cut-off of 240 lbs.
Yeah because it has an actual correlation, whereas BMI is a ridiculously oversimplified measurement designed for population statistics based on what data is easily available, not individual assessment.
Relatedly, there is evidence that certain types of "resistant starch" can help reduce visceral fat. This starch comes from green bananas, potatoes, legumes, etc. It has to be either raw (there are supplements for this) or cooked and cooled.
"Resistant starch intake facilitates weight loss in humans by reshaping the gut microbiota"
https://pmc.ncbi.nlm.nih.gov/articles/PMC10963277/
Edit: Ah, HN submission 2 years ago: https://news.ycombinator.com/item?id=39592367
sample size n=37 of which recruitment only happened in Shanghai without any real control for confounders, only evaluated over a period of two weeks with no longterm follow-ups, the dosage of 40g RS/d is very high (would take about 4-5 large potatoes daily for equivalency or ingesting likely expensive supplement), the crossover compares RS vs CS in the same participants with only a 4 week washout which is a weakness since fermentable fiber persists >4 weeks, also the supplement they used was industry-provided by a starch manufacturer which was weirdly not disclosed
this is a great study if you are an overweight/obese adult without overt metabolic disease, willing and able to consume 90 g/d of starch supplement within a controlled diet, and living in Shanghai with similar baseline fiber intakes endemic to that population. it is extremely not generalizeable to you or even me though I fit more of those characteristics than I care to admit
stay skeptical of small studies like this, friend
> not generalizable
But there's already a general advise on this: eat more fiber.
https://med.stanford.edu/news/all-news/2017/08/hunter-gather...
We're a great ape, our body evolved to process a lot of fiber from fruits and starches. It's the modern fiber-deficient diet that's really weird.
90g/day of fiber is similar to the Hadza tribe diet, where they can consume 100-150g of fiber per day.
Also, the authors claim the starch "inhibited lipid absorption." They do not argue why they used surrogate blood biomarkers instead of residual energy output in fecal samples (which is a better measurement).
sample size is 37, number of authors 29
You can just go on a calorie deficit and it will reduce your visceral fat when you start getting lean enough.
But obviously, most people are a lot more interested in finding a magic food which does this rather than a proven calorie deficit, which is highly effective.
> highly effective
Purely behavioral lifestyle interventions have the lowest long term success rates of all available treatments for obesity. It's especially unreliable if you have weight loss targets higher than 15%.
They are of course still widely recommended due to numerous benefits other than weight loss, but "highly effective" is just wrong in the context of obesity treatments.
> Purely behavioral lifestyle interventions have the lowest long term success rates of all available treatments for obesity.
What? Surely changing one's behaviour - particularly the parts of behaviour that caused the obesity in the first place - is a sure way to stop being obese.
By this reasoning, abstinence-only sex education is a sure way to stop teen pregnancies and spread of STDs.
The issue is not whether it works; it’s whether someone can stay compliant long enough for it to work
Long enough in this case meaning forever.
Behavioural changes work, the issue is that most people don't actually change their behaviour.
To do it right it requires quite an effort to no go too much into calorie deficit.
It definitely is not "you can just go on a calorie deficit", that is how jo-jo effect works.
For average person that has children, full time job, and whole range of adult responsibilities it is hard. Not impossible but hard, this is why people are looking fo easier solutions.
Why not, though? Eating is fun and pleasurable. If we can figure out a way to eat the things that we want, in the quantities that we want, while maintaining our health, why shouldn't we try?
I've lost weight through forcing myself into a calorie deficit, and it works really well, but it's not particularly fun.
You always end up with the people pushing these foods being those who sell them. And then others start selling fake foods with similar claims.
For the "eat to get slimmer" claim, I think we're at the point where "extraordinary claims require extraordinary proof."
Did you get an iberian to lay the pattern in your vomitorium?
Abstention is commercially a no go zone, eating 'different' is a goldmine. It is why 'going on a diet' in the 1970's still meant eating less, while starting in the 1980's the phrase was turned into just eating the latest industry fad miracle food.
You can induce a calorie deficit by eating foods that fill you up but don’t have many calories. Also avoiding the sugar-spike carbs cause leaving you even hungrier shortly after works also.
A good dietician is worth a few consults if you don’t have the will power to just fast. And as a bonus you don’t lose muscle mass as well because they’ll focus on keeping protein up.
>A good dietician is worth a few consults if you don’t have the will power to just fast. And as a bonus you don’t lose muscle mass as well because they’ll focus on keeping protein up.
Fasting is like using a nuke where a bullet would do.
How will a dietician measure your maintenance calories? How will they continuously update your macros and calories when your maintenance calorie change week to week?
I am making a claim here: most dietician will not be able to track your maintenance calories better than MacroCodex's algorithm.
Many dieticians simply rely on BMR/TDEE static formulas, and the limitation of this approach is that it cannot reliably track a user's actual maintenance calories well through the span of their dieting journey.
The vast majority of people who lose weight by calorie restriction gain it back, so I wouldn't call it highly effective. Short term yes, but long term, definitely not.
Why do they gain the weight back though? I'd hazard a guess they stop the calorie restriction and go back to their old habits.
Short term "diets" are nonsense. The solution is permanent lifestyle changes.
> which is highly effective
How are you defining highly effective? In the sense that a body will definitely lose weight when starved? Or in the sense that counting calories is broadly effective as a weight loss strategy?
The former is painfully obvious and entirely unhelpful, and the latter is provably false.
Counting macros is extremely effective. The general population doesn't have the discipline for it, but amoung sport coaches, actors, models, bodybuilders, this is *the* technique for achieving goals.
Anyway what's cute about this is that this isn't novel phenomenon. There are lots of parallels to this in other fields where often effective solutions do exist, but at a system level don't seem to work.
Telling people to diet doesn't fix population level obesity. Telling people about personal financial management doesn't stop people from accruing too much high interest debt. Telling teenagers to stop idolizing instagram influences doesn't fix body anxiety issues. Telling people to stop smoking/drinking doesn't fix addictions. 3-2-1 data backups absolutely work but people lose files all the time.
>In the sense that a body will definitely lose weight when starved?
If your maintenance calories are 2700kcal and you eat 300kcal less than that, is eating 2400kcal starving for you?
Most people cannot tell a difference if they eat 100-150kcal less in a day.
>Or in the sense that counting calories is broadly effective as a weight loss strategy?
Yes, it is, and the reason people fail with it is not because calorie counting doesn't work, but because people's maintenance calorie estimates are often poor.
Deficit = maintenance calories (TDEE) - calorie intake
In this, even if your calorie tracking is on point, a deficit requires you to have a decent estimate of maintenance calories.
To throw a monkey wrench into all this, your maintenance calories often shift downward as you progress in your "diet" journey.
calorie restriction can cause a reduction in resting metabolic rate through "metabolic adaptation". that is, your body gets used to the deficit (by shedding metabolically active tissue and other things*) and burns less calories at rest. so, paradoxically, restricting or reducing your caloric intake can have no effect whatsoever on your weight.
see: https://pmc.ncbi.nlm.nih.gov/articles/PMC9036397/
No, that's incorrect reading of this.
It's already factored in our algorihtm: https://macrocodex.app/knowledge/macrocodex/smart-calorie-bu...
The problem is: average person is bad at counting calories. They overestimate number of calories burnt, and severely underestimate number of calories consumed. Once you get your math right and get into real, not imaginary calorie deficit you'll start losing weight. Rule of thumb: whatever you think the amount of calories is in your current meal, double your estimate.
Mark Stache ( https://youtu.be/L-gNdQZorEE?si=nkwAhZOiAFtY2f44 ) just did a 90 day evaluation. The biggest problem at the level they mention is some intense flatulence. He is also in good shape and had mixed results compared to the study.
IMO my only concern is their dats shows they were actually able to maintain a pretty controlled diet for each participant, I wonder how selection was done. I also would've appreciated some bomb calorimetry of fecal samples, similar to [0] which is the widely cited paper that does link general fiber intake to a lower level of caloric/energy absorption.
Baer, David J., et al. "Dietary fiber decreases the metabolizable energy content and nutrient digestibility of mixed diets fed to humans." The Journal of nutrition 127.4 (1997): 579-586.
I feel like I've heard this story 1 million times before.
I seriously don’t understand why you people need to optimize every damn thing. Eat real food and take a walk for maybe an hour a day. Within a year you will have lost a lot of weight. Stop inventing new terms and just eat reasonably instead of eating like pigs FFS.
"you people"
> The study was conducted in Shanghai, China from 3 July 2013 to 14 October 2016
Figuring out and understanding the physiology of different gut bacteria is not just for people trying to shortcut weight loss while still eating unhealthy food or to be sedentary all day.
Eh, the "real food" of Jamie Oliver and Michael Pollan (shop the peripheries) and such isn't very health promoting. So I'll pass and keep eating a mix of fresh food and cheap food that keeps for a long time like legumes. Kthxbai.
Are legumes not "real food"?
To Michael Pollan it seems they aren't worth mentioning right in the first breath when talking about real food, but perhaps an afterthought. "Shop the peripheries" causes them to be lumped in with potato chips and oreos and other stuff that aren't in the peripheries of a supermarket. I don't accept the same real food dichotomy that they do.
For non-invasive heart disease risk prediction nothing beat ECG, period.
Somehow American Heart Association and its European counterpart are in denial, and still pushing dinasour screening mechanism with very low accuracy for heart disease risk prediction.
The standard risk model for CVD based on PREVENT (US) and SCORE-2 (Europe) like parameters are very poor as reported in the recently published paper on the their accuracy performance by the Swedish team [1]. As all CVD risk stratification with cardiologist review (expert-in-the-loop), the most important accuracy metric is sensivity/recall (avoiding false negative that will escape review) of PREVENT and SCORE-2, 26% and 48%, respectively.
The paper alternative proposal increased the sensitivity to 58% by performing clustering instead of conventional regression models as practiced in the PREVENT and SCORE-2.
These type of models including the latest proposal performed very poorly as indicated by their otherwise excellent and intuitive display of graphical abstract results [1].
[1] Risk stratification for cardiovascular disease: a comparative analysis of cluster analysis and traditional prediction models:
https://academic.oup.com/eurjpc/advance-article/doi/10.1093/...
I'm not sure how ECG relates, how would ECG predict heart disease risk? I don't see any evidence of that, it's not even mentioned in the article you linked, which is odd considering the whole approach of clustering is gathering as many risk factors and relevant test results as are available.
There are lots of different types of heart disease. An ECG can be useful for diagnosing some of them but you're overstating the relative value. For many patients, a CT coronary calcium score or CT angiogram may be more valuable in terms of detecting the type of arterial plaques that might require medical management or major lifestyle modifications in order to prevent a heart attack. These are also non-invasive, although they do involve some radiation exposure.
https://www.mayoclinic.org/tests-procedures/heart-scan/about...
https://www.mayoclinic.org/tests-procedures/ct-coronary-angi...
Having a CAC done is fairly cheap, ~$100 in the US. Insurance typically doesn’t cover it, but if anyone is concerned, it’s worth calling to set one up.
My dad’s doctor said he should get one, Medicare denied it, but he paid out of pocket to get one anyway. He found out he was 95% blocked pretty much everywhere and had a quadruple bypass. It likely added many years to his life and avoided a heart attack.
If you’re under a certain age (I want to say somewhere in your 50s), there isn’t any guidance for what normal is. If you’re in your 20s or 30s, I wouldn’t run out and get one. But if you’re in your 40s with a family history, or up into your 50s and beyond, it’s worth thinking about. I’ve also heard you’re only supposed to get them every 2-3 years, it’s not a yearly thing, due to the radiation.
(I am not a doctor)
It was just added to the recommended screenings list and my doctor expects that insurance will cover it soon because of that. Still at under $100, it was well worth knowing that i don't need aggressive treatment. (Though a quadruple bypass beats a heart attack)
Then again, CAC measures end-stage calcified plaque, not the soft plaque it started as, equally clogged arteries but also able to break off to cause strokes until the body calcified it.
The time to take action is long before you have a CAC score. e.g. Start tracking ApoB regularly, see if you have genetic LPa exposure, and avoid the foods that increase your exposure while ignoring the grifters telling you it's a nonissue.
>For non-invasive heart disease risk prediction nothing beat ECG, period.
Emphasis on non-invasive diagnostic screening as invasive testing like angiogram need to be operated by specialist and can take months to be arranged, and only done after incidents e.g heart attack.
ECG is excellent for generic top level CVD anomaly conditions for examples arrhythmia and ischemia.
CT scans are non-invasive. In most US cities you can schedule one quickly. Screening tests are generally not time critical.
How many ECGs can you sell vs how many other snake-oil products? :)
(Edit: This is intended to be sarcastic. I agree 100% with the comment)
(Edit 2: Added the smiley face)
>How many ECGs can you sell vs how many other snake-oil products?
A lot, probably. You could sell people on the idea that it should be a part of your yearly health screening.
"And if you really care about your health you should do them every 3 months to catch problems early!"
or some such.
This will work short-term sure, but after about lets say, 3 years of no adverse findings, the average person will not take it seriously anymore.
Huh? I get a blood panel every year and 90% of the things it looks for are normal year after year. But there is always 1 or 2 things flagged that I need to pay attention to.
An ECG if it was just part of the normal yearly panel of things that get looked at I don't think ppl will stop doing it just because it doesn't find something right away
> the average person
I do not consider the average HN commenter to be average.
What does that have to do anything. The recommendation is to do a blood panel every year I don’t see anything worse about adding ecg to that
Nobody said anything is worse. Half this thread is satire. But on a serious note. ECG is really time prohibitive, drawing 3ml of blood is relatively quick, and doesn't require specialist training like an ECG does.
What’s the latest on better ecg tech? Can’t an Apple Watch basically do it but they can’t call it that because it’s not approved.
“You’re waiting 3 months between ECGs?”
Whistle: Hope you didn't burn those arteries there mate :)
You can still sell snake oil that's purported to improve ECGs.
We should talk, if you can't beat 'em, join 'em :)
Poe's law in a full swing.
I didn't know... Thank you
Get as many scans you can under insurance. Data is king and Claude happens to chew it all pretty well. Apple Health data by itself and family history is enough to make a starter PDF for your cardiologist.
Getting an ECG, EKG, TTE, CAC, carotid duplex US, lipid panel, CMP, TSH, 25-OH Vit D, B12 + folate were what my cardio recommended before appointment #2 on hypertension. Both of us are data guys.
You don't even necessarily need insurance. Some of those tests you listed are pretty cheap so most people reading this can afford to pay out of pocket even if they're not covered by insurance.
What would an uninsured person do if the tests suggested they needed an medical intervention?
> ECG, EKG
Those are the same thing, did you mean to type something else?
I thought this was pretty well known already. Being “overfat” is the problem, not being overweight (though they’re often correlated). BMI is really easy to measure, and is mostly accurate, that’s why it’s so pervasive. However it remains a pretty rudimentary metric (and really should use the third power or your height instead of the second).
> BMI is really easy to measure, and is mostly accurate, that’s why it’s so pervasive.
BMI is easily misunderstood by people who know just enough to see that it’s imperfect, but not enough to understand why it’s still a valuable screening tool.
I’ve been in the “overweight” BMI range with low body fat before. It’s not too hard to get there if you’re lifting weights and paying attention to your diet consistently for years, but it takes a lot of work to get there. It doesn’t happen accidentally except for people who win some genetic lottery to build a lot of muscle and keep body fat low without trying.
Getting all the way to the obese BMI range while having healthy body fat is only happening for people with an extreme dedication to body building and diet (and let’s be honest, a lot of the people in this category are manipulating hormones too).
Yet whenever BMI comes up some people try to dismiss it as too flawed based on these possible edge cases. The edge cases for BMI exist, but that doesn’t mean it’s not useful. It’s a good general purpose screening tool with numbers that are available. If someone has more precise measurements available, those should be used instead. BMI is a really good first pass screener to determine if a closer look should happen.
At a population level, it's great. For individuals, it can fail in all kinds of ways. For me: it is not very good because my body has very strange proportions. I'm 6'2", but my waist is barely higher than my 5'1" wife, and my torso is nearly the same length as my 6'7" brother.
In other words, for my height, I have a very long torso and very short legs. I think it should be relatively obvious that an inch of leg weighs significantly less than an inch of torso, so at a given level of body fat percentage, I'm going to weigh quite a bit more than someone my same height with more typical proportions, and thus my BMI reads me as more overweight than it otherwise would.
My point is not that BMI is bad or useless or anything else. My point is that it was designed as a population statistic and that it can be fraught when one tries to apply it to any individual with no nuance. A high BMI should cause one to consider and examine your health and weight. But it should not over-ride specific details about your physiology that point in the other direction.
> screening tool
People tend to think in absolutes. Even perfectly rational people fall logically foul to not considering outliers.
> I’ve been in the “overweight” BMI range with low body fat before. It’s not too hard to get there
Did you do that as a natural lifter? It’s hard for me to imagine most guys being able to get into the “overweight” range at < 15% body fat without some assistance.
The farther from average height you are the worse it is. If you are from some part of the world where the average height distribution is near the point BMI based itself you will perceive it to be so much better.
I am only 6' and only an intermediate lifter. I'm overweight, but BMI makes me look obese. It really only takes a normal person a year or so to get to three plates on squat with no supplements other than chicken broccoli and rice if they don't skip workouts. Assuming no injuries. That level of strength easily distorts bmi wildly if you are even a little taller than average.
What percentage of any random western country population do you think has reached three plates on squat, and therefore has to consider this?
IIRC, the farther you are from an "ideal" 19th century Frenchman, the less BMI says about you.
Yeah, people don't want to understand that your body structure messing with BMI is quite real but only a few points. It's unquestionably "wrong" in scoring me higher than my wife despite the fact that she's the one with a few extra pounds. But it scores us both as normal, the difference doesn't matter.
Anything to pretend they aren't too heavy.
>Getting all the way to the obese BMI range while having healthy body fat is only happening for people with an extreme dedication to body building and diet
And sumo wrestlers.
The line seems to be drawn at (effortful) activity level more than anything else. And BMI doesn't say anything about that.
I think the vexation comes from the focus on an attribute that is not directly mutable, per one's agency, because that's easier to sell things related to. Versus action that you have a lot more direct control over (social or physical circumstances notwithstanding).
> The lifestyle has a negative effect on their health, with sumo wrestlers having a much lower life expectancy than the average Japanese man.
(from https://en.wikipedia.org/w/index.php?title=Sumo&oldid=136533...), so I'm not sure this is a counterexample.
Average sumo wrestler bodyfat% is ~25–27%
Yes, it is a pretty high level metric with good correlation a bunch of diseases, but really many of these is because it is ALSO correlated to percent of fat, which is often the more relevant metric. But as you said BMI is so much simpler to measure.
Many active gym people have pretty high BMIs but fairly low fat (because muscle is dense), and unsurprisingly have better outcomes than the average person (if you ignore the share that uses/overuses anabolic steroids and co)
> Many active gym people have pretty high BMIs but fairly low fat
I think this is greatly exhaggerated.
Yeah you can put on as much muscle as Arnold and have a FFMI of about 27 then maybe have a BMI of 34 if you have 20% body fat.
But a very gifted natty might cap out at maybe 24 with a BMI of 30 at 20% bodyfat. But let's be realistic. This is not "many active gym people". This is the guy winning the local strongman meet.
Yes a couple of years training for most people can add a couple of points to BMI but I think people exaggerate how much this is. Go look at a 20lb brisket at costco - you don't see people with that much extra muscle all that often.
I do agree to some extent, but really the overweight threshold for BMI is 25. And 30 for obese.
At 6 feet / 183 cm that it takes 184 lbs / 83 kg to be overweight. From what I could find, for regular gymgoers the typical weight for people around 6feet is 180-190lbs, which put many people around the overweight threshold. I am myself at 24.9, and while not skinny I am definitely in the skinnier half of the people at my local gym.
Going from your size to 27 means putting on 10kg of muscle. That's a beef brisket. Half the guys in the gym don't have that much more musle than you.
Yeah really well muscled guy being BMI 27 is probably ok but by 30 it's not natural muscles that are making the scales go up.
My completely made up rule is you get an extra point for every plate you bench (or squat etc). Its not a dramatic difference. If you bench 225 you’re not overwreight till 27 BMI, which iirc used to be the actual cutoff until they narrowed it.
Obese is hard. Overweight is easy if you walk, take the stairs, do the occasional pushup, and play something like hockey once week. Source: my entire life.
N=1
But specifically, it requires no gym time. Muscle mass is built with through reps not weight, and there are lots of non-gym-rat behaviors that do that. I'm not winning any comps.
And obviously genetics matter, but it look at master level soccer players: athttps://pmc.ncbi.nlm.nih.gov/articles/PMC6239137/
> Many active gym people have pretty high BMIs but fairly low fat (because muscle is dense),
I’ve been in the overweight BMI category with low body fat by being active at the gym and focusing on diet. It takes some work to get there.
If I check the calculators for the obese BMI range, there was no way I could get there without either gaining a lot of fat on top of the muscle. The amount of muscle required to have an obese BMI with healthy amount of fat is absurd.
I believe evidence points towards absolute level of fat being more important than % for overall health.
E.g. 20% bodyfat at 250lbs is still a lot of fat.
Of course it's difficult to ever get very high on absolute fat if at 15% or below.
Not sure I follow the logic here, but happy to be proven wrong if I'm misunderstanding. It's not intuitive to me that a 300 lb. person at 20% body fat is generally at the same risk as a 200 lb. person at 30% body fat.
Fat is inherently unhealthy for you beyond some low baseline level.
Additional muscle is positive for health, but only up to some reasonable threshold. There is no health benefit to having very high levels of muscle, and in fact it may be negative for your health at extreme levels. E.g. many bodybuilders have trouble breathing, sleep apnea etc.
Both people in the example have 60lbs of fat. 1lb of muscle doesn't cancel out the negative health effect of 1lb of fat
Looking for some references on these claims, thanks! What you're saying registers as "makes some sense, but where's the evidence?" to me. I'm not seeing the connection where total lbs of fat is inherently worse than higher percentage.
You won’t find any reference for those claims. Did you know that the majority of people who have heart attacks have normal lipid levels?
It’s not the fat that kills. It’s oxidated lipids that kill.
I haven’t heard that as a cause of heart attacks. Is “oxidated lipids” the phrase to look for in research?
Do short people have much lower risk of heart disease?
The mean height for men at 20-29 is 69.2" and 80+ is 67.1" (measured in 2015-2018, the last data I've found) [1], which could be interpreted as shorter people having lower risk of all mortality. One could say that people are just getting taller over time and 80+ y.o. were shorter at their 20-29, but we also have the median height for 20-29 fro 1970s, when 2018's 80+ were 20-29 - it's actually 69.7" [2], men in the US are getting shorter over time, so unless people naturally shrink 2" with age the data points to shorter people having lower risk of death.
1. https://www.cdc.gov/nchs/data/series/sr_03/sr03-046-508.pdf
2. https://www.cdc.gov/nchs/data/ad/ad347.pdf
Short people have fewer incidences of cancer, so I don’t think you can say that lower overall risk of death implies lower risk of heart disease.
As for 2, men in the US are getting shorter because of immigration which adds many confounders.
I am not saying that. I am saying that the theory about absolute amount of fat being bad for health, as stated by the comment you responded, seems to be supported by data.
People do tend to shrink in height quite a bit at advanced age.
https://medlineplus.gov/ency/article/003998.htm
"People typically lose almost one-half inch (about 1 centimeter) every 10 years after age 40. Height loss is even more rapid after age 70. You may lose a total of 1 to 3 inches (2.5 to 7.5 centimeters) in height as you age."
So people DO in fact tend to lose about 2 inches at age 80 versus their younger selves.
Some are more common in short people and some are more common in tall people. Hypertension is one of the ones more common in short people and is significantly more common than the rest combined, so your overall chance of having some form of heart disease goes down as you get taller. However, the forms of cardiovascular disease more common in tall people (e.g. atrial fibrillation) are more likely to actually kill you.
Its not just absolute amount of fat though you also have to account for intra abdominal fat being much worse metabolically than subcutaneous fat.
Do you have a citation for that? I've had thoughts in a similar direction (specifically around the upper/lower intervention points) but have had no luck finding data.
Does that have to do with sizes of the heart and few other organs apparently being largely constant regardless of height?
Another common misconception is that one is still healthy with high BMI that comes from having lots of muscle. It's not clear that lots of muscle is healthy.
How accurate is it, in practice, for a given individual? I'm not that out of the ordinary proportion wise. I have a slightly longer torso and arms versus my legs, a somewhat muscular-ish baseline and broad shoulders, but I accumulate fat almost exclusively abdominally. My teenage self, lifetime peak of my fitness, no visible body fat, hyperactive football player, qualified as solidly overweight. If I was to listen to it, I'd be called obese before I noticeably start to show body fat.
I often wonder far from the median I am in this regard. I was under the impression that it was pretty accurate for assessing populations, but fell apart very quickly at the individual level. How many "normal"/otherwise healthy people do fall outside BMI's numbers?
It’s a tool not the tool. If you have obese BMI you can… look in the mirror and see how accurate it is. If you aren’t sure take one of the dozens of other tests. People focus too much on it being a one stop shop - it’s not. It’s the start of a dialogue with your pcp and self on assessing your health that’s highly correlated with poor health outcomes.
If bmi says you're obese, you very likely (~95%) are. The problem is that bmi only catches about half of people who are obese.
https://www.nature.com/articles/s41598-020-69498-7
I haven't been down in the normal BMI range since 8th grade. And I was measured at 6% body fat my senior year in high school! BMI has always run several points high for me. For that reason, I've always liked waist to height ratio better.
How about other categories, in either direction? I seem to remember it to be a lot less clean cut at the normal/overweight boundary.
It's not really intended to be applied to individuals at all, but if you're in the "healthy" BMI range then you are probably fine just not thinking any further about your weight and doing something like measuring your body fat percentage would just be a waste of time and a source of stress for some people. If you're outside that range, then it is worth doing some of the more involved things to judge if your weight is healthy.
It isn't accurate. It is a statistical tool meant for easily measuring populations of people. It does not apply in any meaningful way to individuals.
That was my impression as well. I'm just wondering if there are actual numbers to gauge by how much. I'd find it almost concerning anyone would draw any conclusions from it if it's not significantly any better at predicting health outcomes than a coin toss.
BMI is at best 66% accurate, so "mostly" is correct, but what is mostly good enough for?
BMI has known biases in gender, age, and race. It misclassified Asians, women, elderly w sarcopenia, and people with high body fat to lean tissue ratio.
Yeah BMI is sort of a 'good enough' technique but also has some very obvious areas that it can miss. If you fall outside the typical fat to muscle ratio is a good example.
Which for the majority of the population isn't relevant.
The people most obsessed with "BMI isn't accurate" are overweight people making excuses for themselves.
Genuine question: What is the difference between overfat and overweight? Isn’t the extra weight in an overweight person comprised of fat?
A muscular person can be "overweight" by BMI standards but not overfat at all. This is the case for many types of athletes, specially in strength disciplines but not only. It is the case in the fitness world that people ignore BMI and are intesterested in body-fat-percentage instead. This is hard to measure accurately so not so useful metric for the general population.
It's also possible to be overfat without being overweight! These "skinny fat" people often look normal enough but they carry very little muscle. It is a concerning condition because a doctor might not recommend a normal-weight person to hit the weights.
I like to think of this as four quadrants around two axes. Low fat/low muscle is simply skinny. High fat/high muscle is the "big guy/gal" look that I associate with laborers. Low fat/high muscle is an athletic look; unhealthy in extremes (bodybuilding) but generally desirable. High fat/low muscle is skinny fat, which I associate with sedentary knowledge workers.
Different athletes look different. A runner vs a Olympic powerlifter vs a quarterback.
Not necessarily, a bodybuilder or very athletic person might be overweight in the sense of above average for their height but not overfat.
The dominant discrepancies are "expected" fat (boobs, etc), and "unexpected" muscle (cyclists, body builders, hard labour careers, etc). I'm currently around 10-15lb overfat and 40-50lb overweight [0]. Only the former statistic matters.
[0] And that, at least somewhat, tracks visual perceptions. Nobody looks at me with a shirt on and believes I need to lose weight, because 10-15lb isn't _that_ much extra on a tall frame. If I were 40-50lb overfat then that would be painfully obvious regardless.
What is the line for "overfat" in this framework?
In my mind, it's equivalent to subtracting a coarse estimate of how much extra muscle by mass I have compared to the median adult male they're using to construct BMI charts.
My actual methodology is pretty crude though -- when I was 15lbs lighter I had borderline visible abs and other visual indicators of being around the 15-20% body fat mark, and aside from gaining weight I don't have any reason to believe I've had any notable muscular atrophy since then, so I'm estimating the actual excess fat in that ballpark. It's be easy for numbers to be off 10lb or more, but even then it'd still indicate the overfat surplus being much less than the overweight surplus.
A better methodology uses calipers and various skin measurements to estimate true body fat percentage.
I've been considered borderline or obese by the standard BMI index for 20 years at least, but for a lot of that had very little to no visible extra weight. A lot of that was just plain having more muscle than the average the standards are built around, but I also suspect BMI gets to be really inaccurate for tall people. I would look anorexic if I had to drop enough weight to be considered not overweight.
"Overfat" just refers to having too much fat.
"Overweight" can mean the same thing for weight, but it also refers to those with a BMI specifically between 25 and 30, and those with BMIs greater than 30 are classified as "obese".
But it's actually not just being "overfat".
It's specifically a high level of visceral body fat.
Genetics determines which parts of the body gain fat first as you gain fat overall, and some people have the unfortunate genetics to gain it first viscerally and some people have the fortune to gain it there last (and everything in between).
This means that you can have different people with the same body fat percentage but drastically different disease risks.
But yes this was also known already.
That's why it's been recommended to take a waist measurement alongside BMI to get a much more informative screening tool. Waist-to-height ratios are another alternative.
A nitpick about the title: Not strictly abdominal fat, but visceral abdominal fat, which surrounds the organs. Not all abdominal fat is visceral; in fact, in many people the majority is not. The article mentions visceral early on, which is the subject.
If you have a lot of abdominal fat then you also have visceral fat so it's just a proxy
This is not true.
It is what is called “skinny fat“.
If you are skinny fat you still have noticeable abdominal fat. You might not see it when somebody has a t-shirt on but it's still very obvious
It's not a remotely good proxy
Seriously, you don't think there's a connection between visceral fat and abdominal fat even though there's plenty of evidence that there is along with just common sense?
It's just a particular type of abdominal fat so obviously the more abdominal fat that you can see it means you also have more of the type that can't see as well... It's not that complicated
A summary:
Thirty years after we learned that abdominal fat distribution matters, large-scale longitudinal evidence shows that waist measurements meaningfully reclassify cardiovascular risk beyond BMI alone.
BMI isn’t a good metric, this has been known for a long time.
For example, I’m 45yo/178cm/93kg and am obese by BMI measurement. However, my body fat is 20% (Dexa), VO2 of 50 (lab) & have the aerobic fitness to run a half marathon after work and not care.
I’m not surprised that you need other metrics like hip/waist ratio, measured body fat, visceral fat, etc to better understand the composition of someone’s body and how it might relate to health outcomes like heart disease.
So this study basically compares,
BMI
Waist circumference (WC)
Waist to hip ratio (WHR)
Subsequent risk of nine cardiovascular/mortality outcomes in >260,000 people followed for ~20 years
To make it even more useful they should have included DEXA scan bodyfat%.
Also, BMI becomes somewhat biased at height extremes because body mass doesn't scale exactly with height². Humans aren't geometrically scaled copies of one another and empirical scaling exponents are often somewhere between 2 and 3. Conventional BMI tends to read relatively high in very tall people and relatively low in very short people. But changing the exponent would only fix one relatively small limitation of BMI
For better height adjusted replacement for BMI itself, one option is Trefethen’s BMI
WHR and WC is positively correlated to bodyfat% but this may get distorted for strongmen or sumo wrestler who tend to have much higher than average lean mass, may also have higher WC and WHR but difference maybe waist to shoulder ratio, they tend to have much bigger and powerful shoulders.
what's interesting is, for sumo wrestlers specifically, WC still correlates strongly with BF% one study reported r ≈ 0.86
There is a category in fitness called "skinny fat" where you are at low bodyweight (so low BMI) but your fat mass is relatively higher when compared to lean mass, so higher bodyfat%
Many skinny fat people refuse to believe they carry higher bodyfat% because they think they've low bodyweight so they can't possibly carry higher fat, which is wrong.
If you are interested in knowing more about bodyfat, this may help you: https://aretecodex.pages.dev/knowledge/measure/bodyfat
> Those with obesity and low WC [waist circumference] were not found to be associated with a significantly different risk of outcomes compared with those who had normal weight and low WC, except for all-cause mortality, for which risk was significantly lower.
If I'm reading that right, it sounds like obesity (and therefore BMI) is still a better predictor for all-cause mortality. Perhaps waist circumference is better at predicting cardiovascular risk but BMI is still useful.
This is new? I thought they have been saying this for years
Same for me, no one considers BMI to be a good indicator of anything, but it is better than nothing, and more importantly, it is super simple.
Any idiot with a bathroom scale and a measuring tape can do it. And by adulthood, height doesn't change significantly and you probably know it, so you may not even need that measuring tape. Other metrics need specialized equipment, error prone or complex procedures, etc... I don't even know how to make a waist measurement. Where exactly? How relaxed should the subject be? How long after eating?...
That's the value of BMI: simple repeatable. Not the best but enough to get and idea and make statistics.
> And by adulthood, height doesn't change significantly and you probably know it ...
But height does change in adulthood [0]. On average people living past 40 gradually lose height. At age 80, it's likely height loss will be >=2 inches. This loss is reflected in higher BMI even when body fat content hasn't changed. Average BMI increase isn't large, but think about a person losing 4 or 5 inches of height while maintaining body fat unchanged.
Self-reported height is generally greater than measured height. Adding 1/2 to 1 inch is common (per experience measuring height). "Height inflation" has modest effect on BMI but problematic in research and workup for medical procedures. In the latter cases, measuring height is necessary.
[0] https://www.uhhospitals.org/blog/articles/2024/10/why-do-peo...
They have. BIM is usually talked about in the same breath as waist circumference which would be a better measure of abdominal fat.
I
and because it is comparative ratio (cm / cm), it works in any length metric. CMIIW
You can control your CVD risk.
Cutting saturated fat to under 15g per day and increasing intake of viscose fibre (e.g. beans) will reduce your LDL particle count in a few weeks, which reduces your CVD hazard ratio. You can measure your LDL and look up the papers yourself. Statins will reduce it a lot too (potentially with side effects). Replace solid fats like butter with liquid fats like olive oil.
Literally any amount of regular exercise, including walking, will decrease CVD HR. The more the better (up until quite a large amount e.g. professional athlete). The more your heart is steadily pumping during exercise the better. Every bit helps reduce CVD risk. Movement is medicine.
For the love of God do not smoke. Literally one of the surest ways to die a horrible death. Stopping smoking reduces CVD risk by a large amount.
Do not give yourself diabetes by eating vast amounts of sugar. If you are doing this, stop. Not having diabetes decreases CVD risk.
Other factors you probably can't change so focus on these.
Doctors, if I got anything wrong please correct me.
> Do not give yourself diabetes by eating vast amounts of sugar. If you are doing this, stop. Not having diabetes decreases CVD risk.
Not eating vast quantities of sugar is good advice, but it's not the direct cause of T2 diabetes. The best evidence suggests that T2 diabetes is caused by the accumulation of fat in the liver and pancreas. See the twin cycle hypothesis. To prevent diabetes, one needs to maintain a weight low enough where the body isn't storing fat in the liver and pancreas (everyone has their own individual threshold for this). If you're pre-diabetic, lose enough weight and most people will regain insulin sensitivity.
> Do not give yourself diabetes by eating vast amounts of sugar.
This can help sustain a high level of exercise (the more the better). Certainly don't if you're sedentary, but the sugar during exercise is really helpful for getting in 10+ hours/week of exercise.
I think the recent stance (not really recent in terms of assumptive idea, but now there is evidence) is that not all forms of sugar intake are equal. For instance, habitually drinking beverages with sugar in them (what are called sugar-sweetened-beverages in literature) is associated with a risk of developing T2D, where getting sugar from normal foods isn't really.
https://link.springer.com/article/10.1007/s13668-026-00740-w
You said all this like you know something, but you didn’t bring up oxidative stress once. I mean, smoking is the leading cause for increasing oxygen stress in the body so you kind of mentioned it there but oxidative stress can be controlled with nutrients like zinc, copper, and manganese.
> Studies have shown that visceral fat, which is fat that surrounds the internal organs in the abdominal area, is associated with chronic diseases like heart disease and diabetes, while subcutaneous fat, which is located directly under the skin, is not as strongly associated.
How does one determine if one has an excess of visceral fat?
A DXA (DEXA) scan will quantify visceral fat for you. This is a non-invasive scan which uses a low-dose x-ray. Most cities have some sort of sports medicine facility where you can get one. It's typically not covered by health insurance but fairly cheap to pay out of pocket.
https://health.ucdavis.edu/sports-medicine/resources/dxa-inf...
A waist measurement is the cheapest and simplest way other than just looking.
You want to make sure you measure under similar conditions, like in the morning after relieving yourself (for example).
If it's too high, losing a ~0.5-1 lbs per week while strength and endurance training with progressive overload will get it down sustainably.
https://www.barbellmedicine.com/blog/visceral-fat-waist-vs-w...
There are scans for like $50 that will tell you. Google Dexa scan or something like that.
$50? Are you talking about US Healthcare where $50 just gets you a call to the receptionist?
Calls to the receptionist are universally free. Your hate on the US healthcare model (not without flaws) is detached from reality.
whats wild is there are people who look very fat - who have lots of subcutaneous fat, who don't have visceral fat. The excessive subcutaneous fat can be hard on your joints but doesn't seem to correlate to other health issues.
Very interesting, now if only you could measure abdominal fat without need expensive specialists.
https://www.lih.lu/en/visceral-fat-calculator/ (thigh one)
https://en.wikipedia.org/wiki/Waist%E2%80%93hip_ratio (hip to waist)
take a look at myticker.com
(previously at https://news.ycombinator.com/item?id=45857053)
Sugar is a drug and this whole discussion beats around the bush.
For two people that are the same height, one could have X lbs of pure muscle, and one could have X lbs of pure fat, and they would have the same BMI. Color me shocked that it is not always a good predictor of disease.
My problem is it’s usually the second guy advancing this argument.
I am not sure if this is adjusted appropriately for different groups who are much more or less pre-disposed to heart disease.
The irony of BMI is that people with plenty of muscle mass are more likely to have a high BMI as well as lowered risk for heart disease.
BMI was never meant to be used as a diagnostic measure. BMI is just a rough filter for large data sets, and entirely dependent on the average height and habits of that population.
Anyone taller than about 6'3" could tell you the recommended weight according to their BMI has always been absurdly low. If it's a printed chart on the wall, they might not even be on it.
BMI is not a good metric for really short and really tall people.
The "ideal weight" of a person is proportional to height to an exponent somewhere between 2 and 3. Simple physics would say 3 but because tall people are not just scaled up copies of small people, it is closer to 2 in practice, maybe around 2.3, but we say 2 because it is easier to calculate.
The downside is that BMI overestimates the "ideal weight" for short people and underestimate it for tall people. But BMI is not great at capturing exceptions anyways, so there is little interest in "fixing" this.
This is a common misconception. BMI while an ok population metric, for individual's the biggest problem with is its poor sensitivity - it fails to classify people as obese who are obese.
Using your 6 3" male as an example, they are significantly more likely to be clinically obese (using waist circumference, body fat % etc) at a weight lower than BMI cut-off of 240 lbs.
It only fails to classify people with excess body fat who are in the healthy weight range.
It's really good at catching people who are obese who are overweight.
Americans that are 6'3" (190.5cm) are about 1.5% of the population. It is a tiny fraction of the population.
It's like 25% of the men in my family. I am but a mere 6'1". What do?
Yeah because it has an actual correlation, whereas BMI is a ridiculously oversimplified measurement designed for population statistics based on what data is easily available, not individual assessment.
It doesn’t matter how fat you are or how much cholesterol you have in your blood. What matters is the oxidative stress that oxidizes the lipids.
They need to figure out a way to reliably Measure OXLDL.
The 2000's called. We've known this for decades because we did a LOT of studies back in the day when you could still get government funding.
how does it compare to cholestrol ?
just got statin at 44 :(
i am not fat and workout ( although diet can use some improvment)