More Evidence That a Healthy, Normal Weight Is Neither


A literature review published today in The Journal of the American Medical Association confirms earlier research indicating that the government's notion of how much you should weigh does not correspond to mortality risks for people with different body mass indexes (BMIs). Looking at nearly 100 studies, Katherine M. Flegal of the National Center for Health Statistics and three other researchers find that people in the "normal" BMI range of 18.5 through 24.9 (which is not in fact normal, since most Americans exceed it) were more likely to die during the study period than people in the "overweight" range of 25 through 29.9. Even people in the BMI range corresponding to "grade 1 obesity" (between 30 and 35) were no more likely to die during the study period than people in the government-recommended range, although people with "grades 2 and 3 obesity" (BMIs of 35 or more) were. The New York Times notes that "the report, although not the first to suggest this relationship between B.M.I. and mortality, is by far the largest and most carefully done." Similar patterns can be seen in studies of medical spending associated with various BMI ranges, where extremely obese people are the ones with substantially higher annual costs.

Do thinner people have a higher mortality rate because they are more likely to smoke or because they have lost weight due to illness? Flegal and her co-authors say the data "provide little support" for those explanations. "Our findings are consistent with observations of lower mortality among overweight and moderately obese patients," they write. "Possible explanations have included earlier presentation of heavier patients, greater likelihood of receiving optimal medical treatment, cardioprotective metabolic effects of increased body fat, and benefits of higher metabolic reserves." 

Another possible factor: BMI, which is your weight in kilograms divided by the square of your height in meters, is not a very good measure of obesity, since it does not differentiate between muscle and fat. (If you are five feet, nine inches tall, for example, you are considered "overweight" at 169 pounds and "obese" at 203, whether you are a bodybuilder or a flabby office worker.) Furthermore, extra fat in itself is not necessarily a health problem. "Fat per se is not as bad as we thought," one expert tells the Times. "What is bad is a type of fat that is inside your belly. Nonbelly fat, underneath your skin in your thigh and your butt area—these are not necessarily bad."

Whatever factors explain these mortality rates, it is increasingly clear that the definition of obesity as problem, let alone an "epidemic" requiring government intervention, hinges on official standards with little basis in reality. If the share of American adults whose weight poses a life-threatening danger is closer to 6 percent (the share classified as extremely obese) than to 69 percent (the share deemed "overweight"), that makes a huge difference, whether or not you think trying to move those numbers is an appropriate function of government.

In case you are not confused enough by the idea of a "normal" and "heathy" weight range that is neither, last month the Times reported that "17 percent of children under 20" have "a body mass index at or above the 95th percentile." If that sounds impossible to you, you are right: A few days later, the paper clarified that the definition of obesity in children is "based on a comparison of a child's body mass index to growth charts from a reference population" of children in the 1960s and '70s, rather than "a comparison of a child's body mass index to measurements of the current population of children." The mistake illustrates how the press often tosses around obesity numbers without much thought about what they actually mean. So does the correction, which raises the question of why those weights from 40 to 50 years ago are automatically considered better.

NEXT: Greek Food Bank Struggling to Keep up with Demand

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  1. "BMI is so fake. It's all just made up."

    /400 pound woman in the endocrinologist's office eating a slice of cake out of a Ziploc bag at 8:30 in the morning.

  2. BMI, which is your weight in kilograms divided by the square of your height in meters, is not a very good measure of obesity, since it does not differentiate between muscle and fat.

    WRONG. It's your weight in pounds divided by the square of your height in inches multiplied by a conversion factor of 703. This is the AMERICAN internet. (You can tell because it has a BMI of 31.)

    1. Just how fat are you?

      1. HA! You're barking up the wrong tree, my friend. My BMI has never been above 22.

        1. Just how fat is your mom?

          1. She's like school on Saturday.


              Well, now that I think about it...

            2. No class? A punishment? A building? Dead?

              There are too many to pick just one. Please let us know the punchline so we can judge if it fits here.

    2. Ballpark, but I don't think the height portion scales very well.

      1. What do I know? I'm a product of the AMERICAN public school system.

        1. I like yours better. I scrape the top of only overweight instead of obese. I don't know that 6'9", 275 is really obese like my betters in the government do, but at least I'm not more likely to keel over dead.

          1. Those dimensions make you a freak to which no normal scale was meant to be applied.

            1. A fact that is reinforced for me every time I buy clothes. Or, well, go out in public.

  3. Homer: [reading screen] "To Start Press Any Key". Where's the ANY key?
    I see Esk ["ESC"], Catarl ["CTRL"], and Pig-Up ["PGUP"]. There
    doesn't seem to be any ANY key. Woo! All this computer hacking
    is making me thirsty. I think I'll order a TAB. [presses TAB
    key] Awp...no time for that now, the computer's starting.

  4. The mistake illustrates how the press often tosses around obesity numbers without much thought about what they actually mean.

    No wonder, as the press, most of the time, tosses around numbers of any kind without much thought about what they actually mean, like:

    a) The number of poor people
    b) Income
    c) Polar bears
    d) Temperatures
    e) Air quality
    f) Taxes
    g) Budgets
    h) etcetera...

    1. Insert my usual complaint about percent vs. percentage points here...

      1. Picky, picky...
        How about one of those "X DOUBLES THIS YEAR" headlines, where last year's quantity was, oh, 2 of 'em?

        1. Stupid, but at least not mathematically wrong.

          1. You're right, but it seems to be used to purposely mislead.

            1. For sure. But so is the percent(age point) thing. Although that might not be purposeful.

      2. My pet peeve is when people, talking about something like income, confuse the change in the average with the average change.

    2. Did you know that the middle class makes up only 20% of the population when you define the middle class as the middle quintile? I read it in a newspaper, so it must be both true and significant. The media are also good at making the most amazing findings from nonrepresentative data sets.

      1. Is that 20 percent or 20 percentage points?

  5. I prefer using the John/sarcasmic scale as a measurement of health. If either one is attracted to a woman then she is unhealthy.

    1. BMI seems uninterested in distinguishing between thin women with no chest and thin women with lots of chest.

    2. Finally, an objective measurement.

      If told this story before, but...

      My diabeetus doctor told me a of a patient who couldn't get his blood sugar down and couldn't lose weight. When they looked at his self-reported food intake, he was eating 800 grams of carbs a today. 800.

      1. Holy shit.

      2. So, how much of that was cake?

        1. "Hi. This is Wilford Brimley. Welcome to Retardation: A Celebration. Now, hopefully with this book, I'm gonna dispel a few myths, a few rumors. First off, the retarded don't rule the night. They don't rule it. Nobody does. And they don't run in packs. And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berserker mode; come at you like a whirling dervish, all fists and elbows. You might be screaming 'No, no, no' and all they hear is 'Who wants cake?' Let me tell you something: They all do. They all want cake."

      3. HIPAA rules don't apply to fatties.

        1. No identifying info was used here.

          1. I dunno, under HIPAA, it's probably illegal to mention that you went to the doctor.

          2. I was instead thinking of the doctor relaying an anecdote about one patient to another. Also, I like to make HIPAA jokes.

      4. If it wants people to lose weight and follow its nutritional guidelines, why does the government insist on providing all of its guidance in some obscure system of weights and measures?

      5. But he was avoiding that icky fat, right?

        Also, I have an urge to post this.

  6. Posted earlier, but worth a repeat: New food Nazi.
    "The food industry has complete license to put any amount of sugar in any food it wants to. That's just not OK,"

    1. As if any amount of sugar in any food isn't bad enough, the food industry apparently has complete license to force people to buy and consume said food.

    2. His main goal, he says, is to get fructose identified as a potentially hazardous substance that should be regulated by government, much as alcohol and tobacco are.

      That's bound to end well.

      1. Thousands of dues paying union employees to administer the new regulations.

        It's not about the effectiveness of the regulation, but how big your empire is.

        Who cares if it works or not? We get a new Czar and a boatload of six-figure salaries.

        Government exists for itself.

        That's the problem with you damned libertarians, you keep griping about whether or not these programs work. Of course they don't work. It's about the Renovation Program, spare parts for 25 years...

        You libertarians have no vision.

  7. I tend to think that being a little pudgy is probably at least as healthy as being somewhat skinny, but I won't put much faith in any study that is based on BMI as the measure of how overweight someone is. Muscular, fit people have higher BMI. That may well account for all of the difference shown in this study.

    1. Impedance testing is the way to go. It might not be insanely accurate but it's pretty reliable one fatty to the next.

  8. More Evidence That a Healthy, Normal Weight Is Neither

    I won't tell the wife...

  9. What is bad is a type of fat that is inside your belly.

    I hate oversimplification. What's bad is visceral fat, which is fat that surrounds your organs or can actually be inside them. Visceral fat is most often the result of insulin resistance, which jacks serum insulin which causes fat storage even when you should not be.

  10. Heard this on NPR this morning. Guy in charge of the Harvard School of Public Health [insert requisite comment about state of modern Public Health here] complained that the study was "utter rubbish" (if I remember his exact quote).

    While he did have some valid criticisms, namely, that merely taking all 'heavy' people and all 'normal' or 'thin' people and seeing who died last wasn't a valid metric, because it didn't control for why people were of normal weight (diseases causing them to lose weight, etc).

    While on the surface that's true, the problem with the whole 'overweight' concept is that we've tagged certain diseases to be 'obesity related', just as we did with smoking. Thin people can get 'obesity related' diseases just like non-smokers can get diseases associated with smoking (heart disease).

    So the problem is that if you take all overweight people and tag any 'obesity related' disease they have as a result of their being overweight, you're committing the same logical fallacy.

    You'd have to create a study which also pointed out thin people who had diseases which could arguably fall under 'obesity related' such as diabetes, heart disease, joint problems etc.

    Not easy to do.

    1. When you said a guy from Harvard, at first I thought you might be talking about that clueless fat fuck, Kelly Brownell, "obesity expert", but he's from Yale.

      1. Yeah, Kelly Brownell wouldn't have had any rebuttal that would have made an ounce of sense.

  11. BMI is based on some statistical work in the 19th century and was NEVER intended to be used on an individual basis. See this:


    1. You know who else did statistical work in the 19th century which put people with certain genetic traits into specific categories?

  12. What about quality of living? A longer life isn't worth much if you're going through it being a fatty.

    1. I'd have a higher quality of living if I didn't have to hear Nanny Staters trying to tell me (and openly wishing they could order me) how to live my life.

      Why do you ignore the quality of life value of being left alone?

  13. Fat, thin, whatever. Health is determined by how your body functions, not how it looks. Are you 5'3", 180 lbs, but can run a 6 min mile? Then it's probably cool. Are you 6'0 180 lbs and collapse after 5 steps, you should probably change your ways. The government is the fattest organism on the planet. How about we put that fat fucker on a diet, say a trillion or so.

  14. Is this article a joke?

    "...'normal' BMI range of 18.5 through 24.9 (which is not in fact normal, since most Americans exceed it)"
    "normal" in this context means "normal healthy" not "average." Just because the majority of Americans far exceed the healthy range doesn't mean we should grade on a curve and reset health standards.

    The article then ends with following thought provoking statement: "...[this] raises the question of why those weights from 40 to 50 years ago are automatically considered better."
    The answer to which is this: because 40-50 years ago people's diets were less saturated with fast food, tv dinners, trans fat, msg, sugar, high fructose corn syrup and smaller portions.

    How can anyone look at pictures of people from 40-50 years ago compared to the engorged, stretch-marked, waddling people of today and not immediately see why the average weights 4-5 decades ago were more optimal.

    This is an obesity epidemic and the people who fall into the obese or morbidly obese categories (excluding the very small percentage of those with medical conditions such as hypothyroidism) suffer from a food ADDICTION. Society isn't doing these people any favors by enabling them. They need help, not false justification/ validation.
    This isn't meant to be hurtful or offensive. It's just the truth. This is an addiction, not a new progressive standard of normalcy. As I'm sure recovering addicts from any other addiction will tell you: sometimes the truth is difficult to hear.


  15. Sometimes dude, you jsut gotta roll with the punches. Wow.


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