You’ve made the point that dieting for weight loss rarely works. You’ve also warned that these diets can be hazardous to one’s health. What’s dangerous about losing weight?
A Dropping pounds through dieting has been shown to cause some health problems, including reduced bone mass, which increases the risk for osteoporosis. But the biggest problems probably result from weight cycling, or yo-yo dieting, which is the reality for most people who try to lose weight. Weight cycling has been linked to a host of concerns, including raised cholesterol levels, higher blood pressure, increased inflammation, insulin resistance and even depressed immune function. Consider high blood pressure, which is often associated with obesity. When researchers at the German Institute of Human Nutrition in Potsdam-Rehbrücke looked at more than 12,000 middle-aged men and women for a study published in 2005, they found that obese men and women whose weight fluctuated over a two-year period were four times as likely to develop hypertension as the obese people whose weight remained stable. An earlier Italian study reported that women who had lost weight at least five times in five years were more likely to have high blood pressure than those whose weight remained stable.
If dieting is a bad idea, what should the public health message be?
A Our focus on weight has resulted in widespread body discontent rather than improved health in the popula-tion. Instead, we should be focusing our efforts on what people can do and what we know will make them healthier—such as being physically active and eating more nutritious foods. My colleagues and I did a study, reported in the Journal of the American Dietetic Association, that confirms the usefulness of this approach. We randomly divided 78 obese chronic dieters, all female, into two groups: One followed a conventional weight-loss diet; the other enrolled in the Health at Every Size [HAES] plan, which emphasizes eating in response to hunger cues. Both programs lasted six months, and subjects were evaluated two years after the study’s beginning. By six months, 42 percent of the conventional-diet-program participants had dropped out, but only 8 percent of the HAES members had departed. The dieters did lose weight in the first six months, but two years later they had, on average, regained it all. Women in the HAES group did not lose or gain weight; they stayed the same weight throughout the two years. By the end of the study period, the HAES women showed significant improvements in their LDL [“bad”] cholesterol and systolic [the top number] blood pressure; the dieting group ended up where it had started. In addition, 53 percent of those following a diet reported feeling like failures; none of the HAES women did. So I think our message needs to encourage people to become healthy rather than focus on weight loss.
Let’s face it, though: A lot of people want to lose weight because they don’t like the way they look. What’s your advice to them?
A We need to resist the notion that being thin is the path to happiness. It isn’t. Trying to become thin can make people very unhappy. We’ve become so obsessed with weight that it’s a major revolution for people to say, “Hey, I can choose to see myself as attractive.” We’d all be much happier if we honored size diversity and focused on healthy choices, letting our weight fall naturally where it may.