Do Fat People Live Longer? | Chris Kresser

Do Fat People Live Longer?


Published on

do fat people live longer, overweight people live longer
Avoid turning to BMI as an accurate measure of health. Digital Vision/Digital Vision/Thinkstock

We’ve all heard the recent news story splashed all over the TV and internet: overweight people actually have a lower risk of dying than those of normal weight.  (1) What a shock to the millions of Americans on a weight-loss diet, not to mention the hundreds of health professionals, research scientists, and government policy makers who are working around the clock to combat the obesity epidemic in this country! Could it be that we’re all wasting our time trying to lose weight if we want to maximize our life span? Do fat people really live longer?

As with most epidemiological research, this report needs to be taken with a big grain of salt. While there may be some level of protection to the “extra padding” that many Americans are trying to lose, there are also serious shortcomings when using BMI as a determinant of body fatness. Someone with a normal BMI may have a high body fat percentage, while your average bodybuilder can have a BMI that falls within the obesity range while still boasting a single-digit body fat percentage. So is being overweight really health protective, or is this another case of mass media jumping to unfounded conclusions?

Are you wasting your time trying to achieve a “perfect” BMI?

Tweet This

When Body Fat Is Protective

First, the authors of this study admit that its limitations include a narrow focus on BMI as opposed to body composition as a predictor, and an outcome of all-cause mortality without addressing morbidity or cause-specific mortality. (2) This generalized view of the data leads to an omission of certain factors such as body fatness, overall indicators of health besides mortality, and risk of dying from obesity-related disease as opposed to risk of dying in general. In other words, body composition likely plays a significant role in overall mortality, and overweight people may still be more likely than normal weight people to die from certain diseases attributable to excess body fat. This study does not control for these important factors, and therefore cannot be used to make general health recommendations to the public.

However, this study does bring into question the benefits of weight loss for those who are metabolically healthy. It is reasonable to suggest that having a bit of extra body fat may be generally protective. In an accompanying editorial to this report, Drs. Heymsfield and Cefalu of the Pennington Biomedical Research Center observed that the “obesity paradox” of all-cause mortality may have more to do with survival rates during both chronic and acute disease states, where a small excess of adipose tissue may provide the extra energy needed for recovery during catabolic illness. (3) A slight excess of body fat may also protect against death from traumatic injury, when metabolic rate skyrockets in response to inflammation and infection following the trauma, and body tissue is broken down rapidly.

In any situation where the body’s energy needs are high, having extra fat stores can help prevent the deadly tissue wasting that can cause deterioration of vital organs such as the heart. So if you’re trying to lose the last ten or fifteen pounds, you may be reassured to know that body fat can serve a purpose when it comes to protection against catabolic illness or traumatic injury. Thus, if your overall goal is to live a long, healthy life, that “extra padding” could actually be helpful rather than harmful in the long run.

BMI versus Body Fatness

On the flip side, BMI calculations pay no attention to a person’s body composition. As I mentioned before, a person can be quite lean but still fall into an overweight BMI category if they’re stocky or extremely muscular. And we’ve all heard about the danger of being “skinny fat”, where one’s BMI appears healthy but his or her body fat percentage is dangerously high. In fact, research suggests that the sensitivity of classifying a high body fat mass from a high BMI may be as low as 20 to 50%, demonstrating the potential inaccuracy of judging one’s health based solely on BMI. Therefore, we must consider body composition more carefully when determining the health risks or benefits of being in a higher BMI class. What does the research have to say about the role that body fatness plays in overall health and mortality?

A comprehensive analysis of NHANES data found that for men, an overall BMI of 27 was associated with the lowest risk of mortality, but that both fat mass and fat free mass were more directly correlated to mortality. (4) When body composition was controlled for, the data demonstrated the lowest risk for men at a BMI between 19.5 and 20.5, suggesting that mortality risk is more related to leanness than it is to BMI. Another study conducted on 60 year old Swedish men found that a high percentage body fat was significantly associated with a 40% increase in total mortality, compared with a low percentage body fat, suggesting that a high fat mass is more strongly associated with mortality risk than a high BMI. (5)

A 2012 study found that body fat is inversely associated with mortality in patients with already-established coronary heart disease (CHD), with low body fat being an independent predictor of an approximately 3-fold higher mortality in these patients. (6) This is surprising, considering that high body fat is generally associated with a worse overall CHD risk profile. The researchers also found that higher lean mass was associated with a better prognosis for survival. They theorized that those patients with higher body fat and/or higher lean mass had a better response during times of negative caloric balance (catabolic stress) and may have had more muscular strength than patients with lower body mass, protecting against death.

Another 2012 study found that there is a significant gender difference in survival rates for older adults (≥65 years) with varying BMIs. (7) In both men and women, lean body mass was associated inversely with mortality, where those with the lowest lean mass had the highest risk of dying. The results also showed that higher body fat in women was generally protective against mortality, provided that the waist-to-hip ratio was low. This is an important distinction, as healthy men and women have very different body compositions and must be studied independently from one another.

Take Home Message: Body Composition Matters!

These studies all have their limitations, but the general pattern seems to suggest that a slightly higher BMI with a higher proportion of lean mass is associated with better mortality outcomes for both men and women. For women specifically, healthily distributed body fat is actually protective against mortality, even at higher levels. There are several explanations for this finding, including a greater caloric reserve during catabolic illness, overall greater muscle strength, and possibly a more adequate food intake, particularly for older adults.

It’s important to remember that a person’s body fat may increase for a variety of reasons, and that BMI is a poor indicator of overall health in most cases. As a clinician, I believe certain indicators of health such as insulin sensitivity, markers of inflammation, and overall digestive function are far more important predictors of health than BMI or total body weight. If you’re a metabolically healthy person with a few extrapounds that just won’t budge, current evidence suggests that getting to your “perfect” weight may not increase your lifespan. In fact, if you’re a woman, it may even be counterproductive. This casts doubt – at least from a scientific perspective — on our culture’s (pathological?) obsession with skinniness. It also suggests that maintaining adequate lean body mass by eating a nutrient-dense diet and doing regular weight-bearing exercise may be more important than shaving off those final few pounds of fat.

These findings do not, however, detract from the large body of evidence linking significant excess body fat and positive calorie balance (i.e. overeating) with numerous health problems ranging from metabolic dysfunction to cardiovascular disease. So if you’re substantially overweight and have a higher than normal body fat percentage, nothing in this article gives you an excuse to abandon your fat loss efforts.

Eat high quality, nourishing food, find strength-building exercise that you enjoy, get enough quality sleep, and manage your stress, and you’ll set yourself up for a long and healthy life – even if you’re carrying a few extra pounds along the way!

  1. The BMI scale has always been a ridiculous one size fits all measurement which doesn’t take into account build or musculature.

    The American Institute for Cancer research states “BMI may not be an accurate measure for everyone, including people who have more muscle mass, like athletes; seniors with less muscle mass; or for people under 5 feet tall.”

    Assuming this is correct, and that shorter people are deemed to have higher BMIs than taller people with an equal percentage of fat, I’d suggest that if height has any influence on mortality at all this could skew any calculations of BMI mortality one way or the other.

  2. They also didn’t take into account the fact that many obese people don’t get out and about much, and therefore are less likely to die in car accidents, and other activity related accidents. Living longer does not necessarily indicate living better.

  3. Careful there Chris, fat is now becoming politically incorrect word. Maybe you can use metabolically challenged or something.

  4. Perhaps in a society with a nutrient deplete diet overeating provides more vitamin and antioxidant goodness that those who eat less miss out on.

  5. Is life span the issue or disability? If I am very over weight, how likely is it that I will be disabled or not as I age? Is not the real toll of chronic illness that it robs us of the ability to be independent?

  6. The Pima Indians of North America may be a good example of this. The women become obese in response to the SAD, whilst the men were less likely to, but at the expense of higher rates of type 2 diabetes among the male population. Could this be because the women who became obese had a better capacity to partition excess calories into fat stores, thus protecting them from the ravages of excess blood glucose and PUFAs?

  7. I think there is some merit in the claim, but from a completely different viewpoint. From an Ayurverdic medicine standpoint, people who have a tendency towards being overweight are Kapha types. It is observed that these people, if they don’t become obese, have the most potential for a long life. So, from the Indian medicine perspective, if these people drop the weight, they will live longer and be healthier than other constitutional types, i.e., those with Vata or Ptta as the main constitution, with little Kapha.

  8. This may very well be a case of the age old quality over quantity bit. Think about it. Overweight people may be restricted to doing numerous things and activities, they may suffer from depression, not to mention the social stigma too that comes with tipping the scale way too high. Just look at mass media and how it portrays this whole “thin is in” bit- and that definitely has a huge influence. So overweight people may live longer, but the quality of their life is decreased due to their size.

  9. I honestly believe it depends on the person, their health, level of exercise, etc. I had a great aunt who was ‘obese’ almost her entire life. I have a picture of her in her 20’s and she is at least 200 pounds or so in the picture. She was around 5′ 4″ tall. She had always been a big woman. Into her 70’s & 80’s, she lost some weight and might have weighed around 160 when she died at the age of 86, a few weeks from her 87th birthday.
    My husband’s grandma has always been a large woman, close to 6′ tall, about 200 pounds or so, We have pictures of her in her 50’s and up and she was NOT a small woman in height or weight. She is now 102 1/2 years old and just recently began to have some health issues. And though she is over 100 years, she is far from being thin, though she is much smaller than she was when much younger.
    I’ve known people who are thin who died young (heart attacks, cancer, other diseases); I’ve known people who are fat who have died of the same problems as their thin counterparts. I’ve also known both thin and heavy who have lived well into their 80’s, 90’s, and 100’s. Currently, I have a great aunt (other side of family not related to aunt above) who just turned 86, is disgusted she can’t lose weight (she is definitely overweight), but otherwise, she is in quite good health and gets around well. I like to tease her and tell her she is America’s oldest teenager (like Dick Clark) as it is so easy to forget how old she is as she is active and has a sharp mind.
    I think it is more important to eat well (good real food), move every day, and keep one’s mind active. We’d all like to look like the statues of David and the Venus De Milo, but the reality is, we are all different. One size does not fit all in health or length of life.

    • There is a book called The Obesity Myth by Paul Campos that agrees with you. He maintains that it’s not how fat/thin you are, but rather how active you are that determines health. He also claims that dieting is the best way to GAIN weight. Yo-yoing is very very unhealthy.

  10. Hi Chris

    This is a very timely article for me since I’ve been working, for the last couple of months, on the idea of obesity being a CA (compensatory adaptation).

    I’m a KPT2 (ketosis prone type 2) diabetic and I write a blog on this subject. One of the seminal papers on this type of diabetes shows obesity as being protective. I discuss that here.

    This paper is a perplexing thing that I keep returning to because its data and others like it suggests to me that obesity may be a CA to toxicities in our environment and what we see with obesity is our individual relative sensitivity to these toxicities.

    I am slowly being prodded up a path that is saying that the strong correlation between diabetes and obesity is akin to that of smoke and heat to fire.

    Anyway that is my view from the weird diabetes section.


  11. It’s very simple. If your tummy sticks out more than your boobs or pecks, you are overweight.

    If you carry on eating such huge portions and don’t exercise, you will get fatter.


    • Except that it’s not really that simple Neale. I eat way more in calories than I used to, and only walk to keep my joints flexible, relax my mind, and fight depression in the winter months. I have gone months without walking due to an injury, and continued to lose weight eating like this. I have lost weight, and am continuing to lose weight, eating more saturated fat and calories than I ever did when I ate junk food and when my ratio of meat and fat to carbohydrates was more even. Your body simply processes macro-nutrients differently – it sees excess carbs as something that needs to be stored and stores it as fat. By tweaking the ratios of your intake of fats, protein, and carbs, you can most definitely gain or lose weight without exercise.

      • I agree with you, Ann. Every body is different. Based on my BMI, I am overweight, but I weigh 125 lbs and am 5’4″. I have low muscle mass and more fat than I would if I exercised, which I haven’t done for years. I can eat just about anything and remain the same weight, but I do not consider myself healthy because of this. I do eat pretty well, but have a long way to go in order to be truly healthy. My belly does not stick out past my boobs, either, but that by no means tells the whole story.

        • How are you doing your BMI calculations? I am 5’4″ and 139 lbs. My BMI is 23.9 which is in the normal range.

          • When I calculate it with the formula, my numbers are fine. The problem comes when I get on a scale that calculates BMI or have the skin fold test done. I have low muscle mass, apparently, and fat makes up more of my weight than it should. I always get 30% fat on those things. I am not sure which is more accurate, but my guess is the scale because it actually looks at my individual body composition? Not sure.

      • I agree with everything you said. It sounds like you are eating a paleo diet. So am I. Basically eating this way makes weight loss effortless. I have lost 30lbs in year and half. Kept it off close to 3 months. I have no grains in the house. I eat pastured meat eggs and poultry, greens, cruciferous veggies, tomatoes, avocado, carrots beets and sweet potatoes make up the bulk of my diet. The biggest gains are from going almost pure paleo several months ago. I do calisthenic weight bearing exercise and go for long walks. I am in the best shape of my life. As you said all calories are not treated the same. I

  12. I’ve always been happy to be a little curvy or padded. Health issues aside, I’d like to be slim enough to wear the clothes I like, but curvy enough to have obvious breasts and hips.
    Nothing could make me want to be skinny if it meant losing those two things.

  13. I think another factor is that often, people who have chronic illnesses are very skinny. So it’s not only that extra body fat can protect you in the event of illness, but that illness often causes decreased body fat, skewing the statistics. I would guess that cancer patients, Crohn’s patients, people with eating disorders, etc.. will all tend to have lower BMIs.

    • Bingo Alyssa. That is the BIIIIIG problem with all epidemiological accounts of BMI and mortality. My jaw dropped when I learnt in my biomedical sciences degree recently that no study, including this one, has ever controlled for underweight in smokers, the malnourished and the terminally ill. So actually we still do not know if being thin is a health risk of any kind in general. It still seems likely that it is not.

      The “when times grow hard…” concern makes sense IF times are EVER hard! But if they’re not….?
      Of course there are always unpredictable misfortunes that can befall a person. But the more likely misfortunes are those which come from lifestyles of poor health…

      The jury is still out for me. Personally if I put on weight I put it on around my waist and become less feminine looking, so there is no real appeal for me in plumping myself up.

      • I would venture that Alyssa’s grandfather may have had real-life experiences with world wars and/or depression area economics. Times are hard for many in our country, just NOT, seemingly, for those of us who obviously have enough time/resources to obsess about our health on internet blogs and forums…

        Hard times, the kinds of hard times I referred to above, could happen to any of us at any time. Long-term unemployment due to the economy, natural disasters that disrupt the shipment and delivery of our food sources, chronic illnesses – perhaps this IS the time to get our bodies healthy for the lean times to come?

        I think that as long as we eat a clean diet (for me this means grass-fed and pastured meats and eggs, organic vegetables, nuts, and seeds, and no dairy or grains) our bio-markers SHOULD be okay, whether we are overweight or not. I am significantly overweight, but since adopting a meticulously healthy diet with few cheats or indulgences that aren’t on the “plan”, my biomarkers have improved dramatically. Increased HDL, lowered LDL, lowered triglycerides, HDL-Trig levels down 1-1/2 points, completely normal blood pressure and blood-sugar readings, etc. I’ve gone from being “at risk” for diabetes five years ago, to having two doctors tell me I’m not at risk for anything provided I keep doing what I’m doing.

        To me, this points to the fact that it is most certainly quality of foods and ratios of macro-nutrients, as opposed to quantities of food.

        As an aside, I have not given up on the idea of losing weight (I have lost about twenty pounds without exercise, or really thinking about it at all,) and the longer I eat like this the more control I have over appetite urges, cravings, and the need to eat for emotional reasons. It speaks of the ability of the body to balance itself when provided what it needs for health!

    • Hi Alyssa,

      That may well be true. However, it again underscores the fact that equating thinness with health, as many misguided people do, is not the royal road to health. Many young people have these disorders too.

      Abigail Saguy, author of “What’s Wrong With Fat?”, recently penned an editorial in the LA Times in which she cited a poll of 231 dieters. Three fourths of them said they would take a pill to lose weight even if that meant their life would be shortened as a result.

      That is utterly tragic, especially for women who are most subjected to weight discrimination in this society. You can read her editorial here:

      I just posted about a Swedish study showing significant differences in visceral fat accumulation in women even though the mean BMI of the women with the most visceral fat was slightly lower than in the women with the least. You can read it here:

      Whatever flaws one can find in the study Chris wrote about, it at least shifts the focus away from just relying on weight as a gauge of health.

      This attitude also does a huge disservice to thin or normal-weight people whose health conditions are often overlooked by physicians trained only to screen for medical disorders in the overweight or obese.

      Given the rampant eating disorders, yo-yo dieting and fixation on weight, I think this recent study is actually helpful, not harmful, if it gets us all to focus on being healthy rather than merely losing weight.

      • Hi Ray,

        I definitely agree that weight is a poor determinant of health. However, because of the way the study was conducted, I still don’t think we can say it proves that being thin is less healthy. Still, all of the points you make are valid. To be completely honest, though, I think it’s a little silly to try and dissect studies such as this one to determine once and for all if ‘fat people live longer.’ If you simply look at individuals on a case-by-case basis, it’s usually quite obvious if they’re healthy or not. If they feel good, their digestion and other systems are functioning well, and they don’t have markers for systemic inflammation or insulin resistance or the like, weight seems pretty inconsequential.

        As you point out, however, the value of this study might not be in its scientific merit at all. If, as you say, “it gets us all to focus on being healthy rather than merely losing weight,” that is huge! This might be a rare instance where the tendency of the media to broadcast strong headlines based on weak science works in our favor!

  14. It’s interesting that the more Americans seem to suffer from obesity, the more they obsess about being thin. It’s also interesting to look at the changing definition of healthy (as well as attractiveness) over the last 100 years. Until the mid-20th century, men were seen as healthy/attractive if they were trim; women were seen as healthy/attractive if they had a curvy hour-glass figure (which is the same as having a good waist-to-hip ratio). Today, men must be ripped and women must look like a skeleton. I miss the old days.

    • Bryan, I agree. I often wonder how we went from a “nice curvy figure” being sexy, to “looking like a 12 year old boy” being sexy. 🙂

  15. Great article, and great comment Pia – malnourishment not only interferes with body composition and metabolism, but also hunger and eating habits. It is easy to over eat on “empty calories” and still be hungry!

    I think of the veg*n’s that I know or see – especially the raw vegans – and many have achieved “thinness”, but I’m not so sure about “health”.
    In terms of body composition, I’d guess they have low lean body mass. Since many of them are women, and very few of those do any strength work/training, I’d guess their muscles have atrophied/been catabolised.

    Given Chris’ explanation, I can easily see why some of them seem to have trouble dealing with illness, and why many studies show they have increase mortality compared to mild meat eaters.

    I read somewhere that your neck measurement is a better indictor of metabolic health than BMI – certainly easy to do and track – though I don’t know what the ideal ranges would be.

    I had also read variously that other body measurements – chest/wist/hip ratios are better than BMI, and best used in conjunction with BMI, as Chris mentioned with the waist-hip ratio. Surely it would not be too hard to come up with a “body composition” index based on such measurements and weight. Not as accurate as skinfolds and DEXA etc, but better than BMI, cheap, and, most importantly, easy for people to do and track themselves.

  16. Are there studies that used water submersion to gauge body composition and its correlation with health outcomes?

  17. I wonder if there isn’t another lesson in here also– that the way most people try to lose weight is incredibly bad for you, causing malnourishment and disregulating the body’s ability to recover from and avoid disease. In any case, your advice to be well nourished and pay attention to metabolic health rather than weight or BMI is spot on. Thanks.