Amid increasing awareness of obesity as a major threat to America's health, "size acceptance" advocates have downplayed the risks of excess weight and portrayed negative attitudes toward it as simple bigotry. Not surprisingly, a recent report that overweight people may have slightly lower mortality rates than those of clinically normal weight was met with a "we-told-you-so" from activists. But attempts to use science to promote the joys of fat are both misguided and dangerously misleading.
The study, published earlier this month in the Journal of the American Medical Association, found that overweight people had a mortality rate 6 percent lower than normal-weight people of similar age and gender.
Marilyn Wann, author of a book called "Fat!So?" and a self-identified "weight diversity speaker," touted this research as vindication in a CNN.com column: The mere fact it was reported as shocking news, she wrote, is "a measure of the intensity and pervasiveness of weight prejudice in our society and in our sciences."
But does the new research support the claims of Wann and her fellow activists? The possible benefit found in the study was limited to people who were mildly overweight, with a body mass index (BMI) of 25 to 30. (This may be due to overweight people getting better medical screening, or being less severely affected by weight loss from an illness.) But the report made it very clear that obesity and especially severe obesity -- BMI 35 and above -- are associated with significantly higher mortality rates. Wann herself celebrates her "fat pride"; at 5 feet 4 with a weight of about 285 pounds, her BMI is 49.
Wann cites another analysis of health and weight data published in 2008 as proof that using BMI as a proxy for health can mislabel some overweight and obese people as unhealthy while missing the health problems of some people with normal weight. Yes, of course being overweight is not the only cause of poor health. But the very data Wann cites show that the correlation is indeed very strong. Depending on the criteria used, 8 to 23 percent of normal-weight individuals had metabolic abnormalities associated with a high risk of heart disease and stroke; between a third and half of overweight people and 60 to 70 percent of obese people did.
Indeed, for all the cries of anti-weight prejudice, there is evidence that most Americans underestimate the dangers of obesity. In a recent Associated Press-National Opinion Research Center study, most Americans knew that obesity was associated with high risk of heart disease and diabetes, but fewer than 10 percent were aware that it is also related to higher risk of cancer, respiratory problems and infertility.
At present, about 33 percent of Americans are overweight while another 36 percent are obese. Childhood obesity is a major problem as well, leading to early onset of diseases such as diabetes.
Denial of the risks of fat often has a political subtext, on both sides of the spectrum. There are culture warriors on the left ready to champion just about anything stigmatized by mainstream opinion, and who turn "size diversity" into identity politics. There are culture warriors on the right who are hypervigilant about perceived intrusions on individual freedom and see government efforts to promote healthy lifestyles as nannyism.
We can debate the best approach to combating obesity and the role of personal responsibility vs. societal factors such as advertising. We can also point out the dangers of the thinness cult, particularly for women, that labels even normal-weight individuals as chunky. But denying the very real dangers of being obese helps no one, especially not the obese themselves.