Tuesday, July 17, 2007

News flash: obesity is not a public health crisis

This somewhat circuitous essay by Jay Bhattacharya caught my eye. Bhattacharya is an M.D. and all-around policy wonk at Stanford University's Hoover Institution on War, Revolution, and Peace. (Great name!)

Don't be put off by the offhand judgments Bhattacharya seems to be making early on; the essay becomes more thoughtful as it goes along. His basic premise: obesity is not a public health crisis because it's not contagious, harms only the person him or herself and not others, and, maybe, is not under an individual's control. He makes an interesting point about why fat workers earn less money than thin ones (not because of prejudice, he argues, but because employers "pass through" higher health costs to fat employees); according to Bhattacharya, only fat workers with health insurance earn less. Among those without health insurance, there is no wage gap.

Interesting, but I wonder if the real reason is that the kinds of jobs that don't come with health insurance are so poorly paid that there's no room for a wage differential. Twenty percent less than $20 an hour is significant; 20 percent less than $5 is less so.

The best paragraph in the essay is the last, where he makes a compelling case against setting public policy after jumping to conclusions. Worth a read.

10 comments:

carrie said...

That was a fascinating article. Very well argued. If I hadn't just set my course readings in stone for this fall (Public Health and Individual Liberties), I might have included this. I will keep it on hand for the choose-your-own-topic last unit.

Carrie

1of42 said...

Funny, an extremely prominent public health expert who I happen to know strenuously disagrees with this, and thinks that obesity may be second only to smoking as a public health crisis that can be prevented easily.

This public health expert is also very overweight.

To respond to one quick thing pointed out by Battacharya: of course a widespread affliction that affects no one else is a public health crisis. It's public because in the current system, the costs of health care are not placed solely on the person receiving treatment, but rather spread somewhat more to everyone. A disease does not need to be communicable to be a public health issue. Smoking, except in enclosed spaces (indoors) or in close quarters, doesn't generally have a great deal of negative impact on nonsmokers. Is it a public health crisis? Hell yes.

Harriet Brown said...

Well, since your "expert" is overweight, of course s/he must be correct! (I think that's what we call being hoist on your own petard.) You might just ask your expert how s/he thinks obesity can be "prevented easily." Since upward of 95% of all dieters gain back the weight they lose plus more, it would seem that dieting is not the ticket. Maybe your expert knows something no one else knows? Do share. The two of you could make a fortune.

Battacharya's point is much better made than yours, I'm afraid. Have you looked at any of the mortality statistics recently that show that the lowest mortality rates may be found in overweight and obese people, while the highest mortality rates are found among thin and extremely obese people? This is true even for heart patients. In fact, it appears that fat may confer some protective qualities. The media reports this (when they bother to report it at all) as the "obesity paradox."

1of42 said...

harriet, it's not necessarily about dieting. It's about eating healthy. If one eats healthy (this includes trying to maintain some kind of caloric equality, i.e. calories in = calories out, or somewhere around there), their weight could easily be a non-issue.

My point regarding this friend of mine being obese is that he has firsthand experienced the difficulty in adjusting his lifestyle to reduce health risk from his obesity, and as a result clearly recognizes the difficulty of controlling weight, even when it is obviously affecting one's health. He's not right because he's obese; he just has some insight.

As for your mortality rate facts, you're being a little bit misleading. The studies suggest that in patients that already have heart failure, overweight and obese patients have a better prognosis. Putting aside your implicit misleading through the vagueness of your statement in the comment, there are 2 issues with those studies: (1) they failed to take into account co-morbidities and other demographic factors - often the thin and/or more underweight people have other health issues; (2) they failed to take into account medication differences. Even given those issues, I think there is a more telling, damning reason those studies aren't totally useful. That is, while morbidity may be improved after a person is hospitalized for heart failure if they're obese, it is more helpful for them to avoid hospitalization altogether - which is best achieved by avoiding the risk factors that obesity exacerbates.

I also looked at the obesity study regarding those with symptoms of heart disease surviving better. The main issue with that is the valid point that those patients may survive longer because they are treated more aggressively in general by doctors, something I'm surprised you didn't think about, since you attribute so many statistical differences regarding obesity to peoples' different treatment of those who are obese.

Harriet Brown said...

Hello 1of42,

You're making a pretty big assumption here: that anyone who is fat is not eating healthy. Not so. There are fat people who pile on the junk food and thin people who pile on the junk food, and vice versa. Fat is not a function of "unhealthy" eating--and I don't even like that term because it's definable in so many different ways. We're omnivores; we're designed to eat all kinds of foods, *including* fats, sweets, carbs, and anything else that has over time been labeled "unhealthy."

Many teens who develop eating disorders begin with a campaign to "eat healthy." Obviously this doesn't cause e.d.s but it sure can trigger them. And I would suggest that millions of American women have subclinical e.d.s related to the "eating healthy" effort. So not only is "eating healthy" a mushy ill-defined term, but it has some negative health effects as well as positive. Food should not be anxiety-producing or fear-inducing. Food is fuel and is meant to be enjoyed in the context of a full life. Any time food and eating become the focus of a life, whether it's in terms of "healthy eating" or binging or purging or restricting or whatever, there's a problem.

As for calories in = calories out, read the Kolata book. It just ain't so. Each person has a different metabolism. Those who are naturally thin with relatively inefficient metabolisms can eat 10,000 calories a day and not gain weight. Those who are naturally fat, with relatively efficient metabolisms, can get fat on 2,000 calories a day. Go figure. It's one of the unfair things about being a human being.

Human beings tend to assign meaning to our life experiences. So people who are thin naturally tend to assign meaning to their thinness--i.e., it must be a function of virtuous living, exercise, or whatever they're doing.

I know someone who bikes nearly every day, walks 15 to 20 miles a week, goes dancing often, is always in motion, likes to eat but is not a binger or overeater. And guess what? She's still fat! That's reality.

The reality about the relationship between obesity and mortality, with and without heart disease, is that we just don't know WTF we're talking about. The jury's still way out on these issues and we need more information. What we do know is that the old verities--thin=good, fat=bad--don't seem to be holding true. There's a lot of money at stake in having them remain true--the multi-billion-dollar weight loss industry, the new bariatric surgery field, etc.--but clearly the reality is much more complex than you would like to acknowledge. (And by the way, the big longitudinal mortality study DID take into account co-morbidities.)

For a brilliant exposition of risk factors, see junkfoodscience.blogspot.com. Having brown eyes is a risk factor for heart disease, but I defy you to show that it has causation. :-)

1of42 said...

Give me a break. I'm going to respond, part by part:

Yes, we're omnivores. We are designed to eat a lot of things. However, the things we evolved to eat include far more natural vegetables, fruits, complex carbs and so forth than our current diet, which is far more based off of simple carbs, high fat, bad cholesterol, and so forth. That said, I never made the assumption that every fat person eats badly. Speaking from experience, most of the members of my immediate family are quite overweight, and yet eat very very healthily. That said, the majority of obesity is related to people eating far too much. This doesn't really require proof; frankly, it's pretty much deadly obvious. A ton of people overeat, and eat badly, and are sedentary. That's not to say those things are the only cause, but they are definitely more common than genetic variances. As someone else said on that site you got your most recent blog post from, it's not like genetics has radically changed in the last 50 years - whereas obesity rates have.

Regarding eating disorders: I'm sorry, but people being conscious of trying to eat healthier and less does not qualify as a mild eating disorder. That qualifies as trying to make healthy choices. Nor does being conscious of being an unhealthy weight qualify. If someone were to not eat for days at a time so as to get thinner, then yeah, it would be an ED. But they don't, and a person eating a salad when they'd rather eat a steak is not evidence of some kind of disorder.

Regarding calories: what about metabolism is incompatible with that? If I eat 10,000 calories a day and don't gain weight, and you eat 2,00 and do gain weight, guess what that means? Your calories taken in are higher than those put out! that's the whole point of metabolism - that some people burn energy faster. People are different, which is why some people can eat a lot and be very thin, while some people eat very little and are fat. So while I think you're trying to get at the point that people have a priori differences causing issues with how much they eat, I see where you're coming from in part, but don't be obtuse - calories in=calories out is a concept that is tied intricately to how much energy someone's body burns, and I think you have to have misunderstood what I was saying to say that someone pointing out asymmetrical caloric intakes would disprove that idea.

Regarding people not knowing what they're talking about with regards to obesity and health - yeah, but actually no. There are complexities to the issue, for sure, but like I said, ceteris paribus, a fatter person is more unhealthy than a skinnier person. Not everyone needs to be ripped, with a low BF% to be healthy, not at all, but people walking around at 400 pounds could definitely stand to lose some weight (assuming it's not all muscle, obviously).

Finally, regarding your brown eyes thing, that's a straw man argument and (I hope) you know it. There's a world of difference between having brown eyes being a risk factor, which likely has to do with genetic differences in the brown-eyed population, and obesity, the mechanisms of which have been extensively studied, and shown in a causal way to greatly increase (especially as a contributor to other risk factors) the risk of heart disease and other health problems.

Harriet Brown said...

1of42,
See my response to your comment on my subsequent post re: assuming that fat people eat less healthily than thin people. I think we've belabored this point enough already. You "just know" that more fat people eat crap than thin people. Love your methodology here.

With regard to metabolism, you're once again making a huge assumption here: that if I gain weight eating 2,000 calories a day, I must be sitting on the couch or at the computer all day. LOL! If only my kids could hear that! They know me as She-Who-Never-Stops-Moving.

No matter what you stoutly (ha ha) maintain, 1of42, calories in-calories-out is old news. Read Sims' research on this. Read Kolata. Really. Don't just keep trotting out your tired old mantra that you "know" it's true, because it isn't.

And no, I don't agree that a fat person is necessarily less healthy than a thin person. I'm not talking about those who weigh 400 pounds here. I'm talking about the vast majority of those considered overweight/obese. Fat and fit are not contradictory.

And no, I don't agree about the straw man argument here. The point is, as someone else posted earlier, that correlation is not causation. High cholesterol, for instance, has not been shown to cause heart disease--and in fact, most heart disease happens to people who have no obvious risk factors. That's a scary thought, I know, and how some people deal with that is to get very sure that they know what causes heart disease so they can avoid it.

In any case, this is all circular. I'm clearly not going to convince you. The best I can hope for is that you are exposed to another pov, so that some day, when you're feeling a bit more open, you might ponder a different perspective.

Anonymous said...

The subsidization argument is weak because it is not based on health per se but rather pooled cost. And it should not only include costs of poor health but also savings, such as lower pooled retirement costs. So, the argument starts with hypothetical increased health risks, assumes increased costs, and ignores savings that are inherently linked to the cost assumptions.

There are some areas where pooling of risks creates additional hazzards, but I can't imagine anyone gaining weight just because there is no health insurance charge.

littlem said...

"To respond to one quick thing pointed out by Battacharya: of course a widespread affliction that affects no one else is a public health crisis. It's public because in the current system, the costs of health care are not placed solely on the person receiving treatment, but rather spread somewhat more to everyone."

Then perhaps the more urgent problem is with the system, and not necessarily with the condition (leaving out of the discussion altogether those who self-insure).

You made your prejudices clear in other comments, but a little critical thinking prior to blurting couldn't hurt, surely?

Anonymous said...

1of42 actually did a very nice job of explaining the results of the study that Harriet Brown cited. Harriet Brown, in failing to disclose crucial caveats in the research that she cited, did herself and her POV a grave disservice.

Harriet, I don't know what 1of42's health background is, but his train of thought is similar to that of many MDs and researchers in the field. You, on the other hand, are dangerously confusing correlation and causation.

The article, from the June 20 edition of the European Heart Journal, notes that the obese patients tend to be younger and have more risk factors, increasing their options for reducing their risk vis-a-vis the slender patients who tend to be older with more idiopathic etiology. This flies in the face of your assertions.

Finally, you seem to have some issues with the laws of conservation of mass & energy in that you somehow think that people are not subject to them. Were you to prove that calories in does not equal calories out, you would be up, first and foremost, for the Physics Nobel, not the Physiology or Medicine Nobel.