Moderation is good for you.

 Margaret Wendte

Surprise! A little fat is good for you

The more research people do, the more tenuous the connection between obesity and health problems becomes. As The New York Times reported this week, studies repeatedly show that “overweight and moderately obese people with certain chronic diseases often live longer and fare better than normal-weight patients with the same ailments.” Two startling examples are heart failure and Type-2 diabetes, which are both commonly blamed on obesity. Type-2 diabetes is rising toward epidemic levels, supposedly because people are getting fatter. But lots of normal-weight people are getting Type-2 diabetes, too. And it turns out that they are twice as likely to die as overweight people. So is the villain really fat? Or is it something else?
These perverse results have come to be known as the “obesity paradox.” If fat is so bad, then why do moderately fat people live longer? Why is the death rate for thin but unfit people twice as high as that of people who are obese and fit? Why does study after study find that the ideal weight for longevity is … overweight?

“That’s because it’s pretty much always been that way,” says Glenn Gaesser, director of the Healthy Lifestyles Research Center at Arizona State University and the author of Big Fat Lies. “The vast majority of population-based studies say that people in the middle of the BMI range – the low 20s to the low 30s – have the lowest mortality rates. And that’s about 80 per cent of the population.”

You probably know that BMI stands for Body Mass Index. It has become the universal measure of obesity. A woman with a BMI of 25 (say, 5’4” and 145 lbs., or 163 cm and 66 kg) is classified as “overweight.” With a BMI of 30 (175 lbs. or 79 kg), she’s “obese.” That sounds awful. But in fact, you have to get to the far extremes of BMI – the upper 30s or above – before your risk increases greatly. If she’s healthy, that 5’4” woman might be okay at 227 lb. (103 kg).

Mr. Gaesser and a growing number of other experts argue that fitness, not fatness, is what counts. If your cardio-respiratory fitness is okay, the likelihood is that you are, too. No matter what your weight, you can achieve striking benefits from eating well and exercise. Just don’t expect that diet and exercise will cause you to to lose a meaningful amount of weight, because (unless you are among a tiny sliver of extremely lucky and determined people) they won’t. For most of us, losing weight and keeping it off is next to impossible. “We should be focusing on behaviour, not weight,” he insists.

Mr. Gaesser (who, for the rec-ord, is thin) says obesity simply isn’t as big a problem as we’re told it is. He points out that between 1980 and 2000, the weight of the average American adult increased by about 20 lbs. a year and then levelled off. That’s around a pound a year. The reasons aren’t clear. There’s no solid evidence that processed foods, lack of exercise, TV, video games, or any of the other usual suspects are to blame. To put this weight gain in perspective, a pound a year (which is approximately what I’ve packed on since 1980) works out to around three M&Ms a day.

What’s clear is that the obesity panic is not about to subside. This week, Statistics Canada warned that almost a third of Canadian kids between five and 17 are overweight or obese (Cue the video of the fat kid!). “It’s a wake-up call that we need to make some fundamental shifts,” one obesity doctor told the CBC. “The health of the population is at stake here.” Luckily for us, the fine print is less dramatic. Childhood obesity rates haven’t budged in years, and only 12 per cent of children qualify as “obese,” as opposed to “overweight,” which used to be defined as “normal.”

No one argues that you might as well flop on the couch and guzzle Big Gulps. Most of us should get more brisk exercise (especially me). But it’s nutty to treat body weight as a barometer of public health. How this came to pass is a fascinating piece of social history. Mr. Gaesser explains it as the convergence of cultural attitudes, medical opinion, and those ubiquitous insurance height-weight tables that were first published circa 1959. “The whole culture has been inundated with the message that thin is desirable and healthy, and it’s extremely hard to go against the grain.”

But the medical and moral significance of body weight is now deeply embedded in our culture. Entire empires – commercial, government and academic – have been built on our morbid fear of fat. I have just one small piece of advice. If you want your doctor to stop nagging you about your weight, find a fat one.




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Surprise! A little fat is good for you - The Globe and Mail