Debunking the Obesity Epidemic

[nancylebov]

From Paul Campos:

In fact there has been no weight gain at all over the past 30 years in the thinnest quartile of the population -- whatever (poorly understood) factors have caused Americans to weigh more on average now than they did in the 1970s have had very different impacts across the weight spectrum: thin people have gained no weight, people in the middle weigh 10-15 pounds than they did 30 years ago, while the fattest people have gained a lot of weight, which is exactly what one would expect. Furthermore, as even this story manages to note, there's quite a bit of evidence that the trend toward weight gain in the populace in the 1980s and 1990s seems to have plateaued.

******

The best epidemiological data on the U.S. population is the CDC's National Health and Nutrition Examination Survey (NHANES). This is universally recognized as the gold standard for such surveys, in particular because it's a nationally representative sample that directly measures its participants. NHANES has been ongoing since the 1960s; the most recent data that allows for significant followup is from NHANES III, which was assembled in 1988-1994.

*****

Most recent excess deaths estimates from NHANES III:
Underweight: 38,456
Normal weight: 0
Overweight: -99,980
Obesity Grade I: -13,865
Obesity Grade II and III: 57,515


Underweight less than 18.5 BMI, normal weight 18.5-24.9, overweight 25-29.9, Obesity Grade I 30-34.9, Obesity Grade II and III 35+ What these numbers mean: In the US population at present, we are seeing about 100,000 fewer deaths per year among "overweight" people than we would if "overweight" people had the same mortality risk as "normal weight" people. Note that the majority of people in the US who according to the government's current classifications weigh too much are in this group. The "overweight" category is to the obesity panic what marijuana use is to the drug war: stories about an "epidemic" of fatness depend crucially on classifying the 35% of the population that's "overweight" as being at some sort of increased health risk. This is simply false, and is known to be false by the researchers who are quoted in stories like the one linked above.

But the situation is much more egregious than even this suggests. Note that the NHANES III data reveals that most people who are classified as obese have a lower mortality risk than so-called normal weight people. About two-thirds of "obese" Americans have a BMI of between 30-34.9, and currently we're seeing about 14,000 fewer deaths per year in this group than would be expected if the group's mortality risk was the same as that of "normal weight" individuals.

Only when one gets to roughly the fattest 10% of the population does the NHANES III data begin to find a relative mortality risk higher than that found among the supposedly "normal weight." And even here, the relative mortality risk results in about three times fewer deaths per capita than observed among the "underweight" (there are approximately four times as many people with BMIs 35+ than there are people with BMIs below 18.5).

The comments cover some of the more common questions-- it's not that a few very sick thin people are making the low weight category look dangerous. There probably aren't enough muscular athletes to completely disconnect BMI from fat percentage.

I can't help wondering if the stats for moderately fat people would be even better (and somewhat better for very fat people) if fat people weren't stigmatized. Not only is there the aggravation of (in many cases) being harassed and insulted, it's harder to make money, and there's a risk of having doctors that blame all one's physical problems on fat so that quite serious medical problems may be neglected.

It's very weird to think that you could be living in a society where the culture could be so comprehensively wrong-headed. The way I got past that threshold was to remember that I'd spent 8 (mostly boring) years in Hebrew school, and it wouldn't have been totally wasted [1] if I realized that anti-Semitism proved that the majority can be wrong for centuries at a time.

[1]To be fair, a lot of the folk songs and some of the prayers have good tunes.

Link thanks to andrewducker.

Comments

Furthermore

[supergee.livejournal.com]

I'm with Thomas Szasz on this: An epidemic is something transmitted by germs or viruses. When they tell you a kind of behavior is epidemic, they're trying to control you.

Re: Furthermore

[nancylebov.livejournal.com]

That looks like a very handy heuristic. And holds up logically if I examine "epidemic of behavior".

I gather (probably from RAW) that Reich thought rules about sex were a primary tool of social control-- if the powers that be get you to give up what you want sexually, they have enough hooks into your personality that they can control you in other ways.

I suggest that the same applies to food, and much more so if it's about being hungry all the time rather than restrictions on particular foods while allowing others which are nutritionally equivalent.

Re: Furthermore

[kiya]

I suspect the same is true for all four Fs (feeding, fighting, fleeing, reproduction, as my paleobio teacher said). Get the primal stuff jumping in the right direction and the rationality goes with.

Theory: this is why fear tactics (such as terrorism and the "war on terrorism" both) are effective for social control.

Re: Furthermore

[whswhs.livejournal.com]

Thomas Aquinas's arguments for why heretics should be put to death are based almost precisely on viewing heresy as a dangerous contagion . . . in fact, more dangerous than bodily illness because it threatens not the infected person's mortal body but their immortal soul.

Re: Furthermore

[supergee.livejournal.com]

The two most common metaphors for heresy (including secular ones) are disease and sodomy.

[vr-trakowski.livejournal.com]

http://kateharding.net/but-dont-you-realize-fat-is-unhealthy/

[nancylebov.livejournal.com]

What I posted isn't news to me (except for the details about weight gain leveling off), I just remind my flist about this stuff now and then.

[crystalpyramid]

What if the BMI thing is just centered in the wrong place? And the optimal weight for health is really somewhere in the "overweight" section?

[nancylebov.livejournal.com]

People with unusually high or low weights are at greater risk, but they're a pretty small part of the population. I think they'd mostly benefit from care for whatever might be wrong with them. Trying to change their weight directly is extremely difficult, and a lot of the methods for doing so can have serious side effects, so I don't think changing weight is a good first strategy.

[lysystratae.livejournal.com]

But she didn't say anything about changing weights, she said the way doctors/scientists/etc are looking at the chart should be changed, with 'healthy' being somewhere in the 25-34 bmi range.

[nancylebov.livejournal.com]

I think it's reasonable to deduce that if doctors are looking for the optimal weight for health in this culture, it's with an eye to getting people to be at that weight. Or I might have done a stored rant which didn't quite fit.

In any case, part of my point is that the differences inlife span are really small for the vast majority of people. So it's not just a matter of changing the definition of the optimal weight, but also giving up the idea that weight is an indicator of anything important for most people.

[lysystratae.livejournal.com]

Oh, I agree with your point whole-heartedly (especially since I'm one of those 'amazingly' healthy obese people - according to my insurance company, my BMI is a whopping 48, which seems a bit out there to me, but whatever), i just thought you misread what she was saying.

[thette.livejournal.com]

Noel Figart wrote a great analysis of the history of BMI. (http://noelfigart.com/blog/2008/08/20/analysis-of-bmi/)

[darius.livejournal.com]

According to one of the studies linked from http://wholehealthsource.blogspot.com/2008/12/peripheral-vs-ectopic-fat.html the BMI associated with lowest death risk was 25.3 for men and 24.3 for women -- 25 is in the supposedly overweight range. It looks like subcutaneous fat is harmless or protective while visceral fat promotes metabolic syndrome, and of course BMI misses that difference.

[landley.livejournal.com]

It's not that the BMI is "centered" wrong, it's that the BMI is pseudo-scientific bunk, as becomes darn obvious when you look at the actual formula:

http://www.maa.org/devlin/devlin_05_09.html