May 3, 2001
Fat and Fit
Looking at television and magazine ads these days, you'd think the surest route to health is a diet that goes something like this: an apple slice and a thimbleful of skim milk for breakfast, a carrot with a gallon of water for lunch, four grains of rice, one strawberry and a shot of wheat-grass juice for dinner. Most of us resign ourselves to the fact that we'll never be cover-girl skinny, but that doesn't stop 40 percent of women and 25 percent of men from trying to lose weight at any given time in the United States. These days, however, the old weight blueprint of five pounds for every inch over 5 feet tall is slowly losing ground, as more and more researchers discover that thinness doesn't equal health, fitness does. And fitness comes in all shapes and sizes.
"The medical community says we're eating ourselves to an early grave," said Glenn Gaesser, professor of exercise physiology at the University of Virginia and author of "Big Fat Lies" (Fawcett 1996), "and it's a big overstatement."
Gaesser claims that while there are limits to a person's weight -- a 1,000-pound man, for example, is simply unhealthy -- folks 50 or 75 pounds beyond the weight-chart suggestions may be as healthy as someone who nails the chart dead-on. "A 5-foot-4 woman should weigh no more than 145 pounds, according to the chart, [and have] a body mass index of 25," Gaesser said. "But that woman could probably go up to 200 and not have much to worry about as long as she exercised regularly.
"Studies are quite clear in showing that if you take a fat person of any size and get them eating better and exercising more, their health problems greatly clear up, even if they don't lose much weight," he added.
One of the main ways of determining if you're overweight is by calculating body mass index (BMI) -- essentially a ratio of weight to height. The government has determined that a BMI over 25 is considered overweight, which categorically puts those people at higher risk for blood pressure, diabetes, heart attacks, high cholesterol and other problems. But, according to Gaesser, there are 97 million Americans with BMIs over 25, and "probably 90 million are unnecessarily stigmatized and [said to be] destined for an early grave."
The key to health, many researchers agree, is not weight, but exercise. A good litmus test, Gaesser maintains, is that a man or woman who walks at a brisk pace -- say, 3.5 miles an hour, three to five times per week for 30 minutes -- would be considered fit enough to achieve health benefits. The 30 minutes can even be incremental, 15 minutes in the morning and 15 in the evening.
Dr. Henry Kahn of the Department of Family and Preventive Medicine at Emory University says fat, in and of itself, may not be cause for concern so much as where that fat is distributed throughout the body. Researchers like Kahn have found that abdominal fat poses the greatest health risks but that thigh fat may actually be favorable. "What you read on the scale in your bathroom may not be the best way to measure weight in terms of health risks," he says. In recent years, a waist-to-hip ratio, measuring circumference, helped determine which people were most at risk, but recent studies have shown, Kahn said, that a waist-to-thigh ratio is "substantially stronger for sorting out the people who are at risk versus those who are not."
Several years ago, Kahn compared first-time heart-attack victims with a control group who'd come from the same neighborhoods and who were comparable in socioeconomic status, sex, weight and age. What he found was that while the BMIs of the victims were no different from those of the control group, they tended to have higher proportions of abdominal fat and smaller thighs, whereas the control group tended toward larger thighs and less abdominal fat.
The good news, says Gaesser, is that abdominal fat is the easiest to burn and generally comprises only 10 percent to 15 percent of fat on the body. Besides regular exercise, people who want to lower health risks associated with weight gain should maintain a diet with reduced fat and loaded with fiber, he says.
"We think we're fattening up as a country ... [but] actually, only 10 percent of the population weighs over 200.... We're heavier than we were a generation ago, but only by 8 or 10 pounds," said Gaesser, whose new book about healthy fitness and healthy fat, "The Spark," is due out this year. "That's cause for concern, but we're not bursting at the seams."