Being fat isn’t good for you. We know that being very fat is very bad for you. I don’t think we know much about being a little bit overweight. According to a story  in yesterday’s Washington Post, though, we have begun to quantify just how bad obesity is for our health:
Obesity has started to erode the gains Americans have
made in extending their life spans and will stall the long trend toward
increasing longevity unless the nation takes aggressive steps to slim
down, researchers said yesterday.
Illnesses caused by obesity are already shortening the
average U.S. life by at least four to nine months — greater than the
impact of car accidents, homicides and suicides combined — a
first-of-its-kind analysis has determined.
That’s pretty scary. And there’s a nice chart to summarize the findings. It gives the whole exercise a nice scientific gloss.
Within 50 years, if the trend is not reversed, obesity will cut the
average life span by at least two to five years, which would exceed the
effects of all cancers, the researchers estimated. That could overtake
all gains from healthier lifestyles and medical advances and cause
longevity to plateau or perhaps decline, they projected.
"The take-home message is that obesity clearly needs to
be considered in an entirely new light — it is far more dangerous than
we ever thought," said S. Jay Olshansky, a University of Illinois
demographer who led the study in today’s New England Journal of
Medicine. Several other researchers agreed, saying the finding that
obesity is actually undermining longevity should be a wake-up call.
I’m not so sure, at least based on a summary of the findings that we find on the second page of the article:
If obesity were magically eliminated, the overall life span would be at
least one-third to three-quarters of a year longer, they found.
At first glance, that isn’t much of a wake-up call. I’m supposed to cut back on ice cream for 50 years in order to have a few extra months when I’m 80? Just to make sure I’m sufficiently worried, here come another expert quoted in the article:
"These results are stunning and reinforce the enormous toll that
obesity is taking on the health and happiness of the population," said
Kelly D. Brownell, who directs the Center on Food Policy and Obesity at
Stunning? Enormous toll? Happiness of the population? I wonder if the Center on Food Policy and Obesity at Yale has any vested interest in exaggerating the seriousness of this problem.
Other researchers, however, said the underlying
assumptions were excessively pessimistic. The study assumed, for
example, that everyone who is overweight will suffer health problems.
Whoa. The study assumed that "everyone who is overweight will suffer health problems?" What the reporter should have asked at this point is the definition of overweight. And the definition of health problems. And how those problems were used by the researchers to establish shortened life expectancy. At this point we hear from the only skeptic who is quoted in the article.
"I don’t think this is based on solid, scientific
ground," said Glenn A. Gaesser, a professor of physiology at the
University of Virginia who frequently questions the impact of obesity.
"It’s nonsensical, really."
Notice that he’s identified as a professional skeptic. His evaluation, that it’s "nonsensical" is pretty harsh. But since we don’t learn why he feels that way, there’s no way of knowing if his skepticism is reasonable. So let’s hear from the other side:
But the researchers said their estimates were
conservative in several ways, including the fact that they focused
exclusively on adults. The true impact is likely to be much greater as
obese children age and begin suffering elevated rates of diabetes,
heart disease and cancer, they said.
"It’s sort of like a massive tsunami
heading towards the shoreline," said David S. Ludwig, an obesity expert
at Harvard Medical School and Children’s Hospital in Boston who worked
with Olshansky. "It’s going to peak in a massive public health crisis."
This is a low point in the history of scientific discourse. "It’s sort of like a massive tsunami"? Sort of like? What does that mean? And it’s actually nothing like a massive tsunami. The essence of a tsunami is that it’s a force of nature that comes out of nowhere and gives you no chance to run or hide. Obesity, to the extent it’s a problem, is a problem of our own making and our own choice. It’s not a virus or a tidal wave. It’s not a contagious disease. It’s not an epidemic or plague. It’s something we do to ourselves and if we choose, we can avoid. Some of us can avoid it easier than others. But it’s a crisis of our own making.
When the authors of a study call the problem of obesity a tsunami, I know there’s something else going on rather than a quest for scientific truth. I’ll try and get the original study from the New England Journal of Medicine or from one of the authors and see what I can find about the methodology.