Diet: Yo-Yo Effect in Dieters Who Get Counseling, Too

July 9, 2007

NICHOLAS BAKALAR

People lose significant weight with formal counseling programs, but they are likely to put it all back on within five years, a new study reports.

While it is known that such programs work only temporarily, the effect has been hard to quantify. The researchers used statistical techniques to combine data from 46 randomized controlled trials of counseling programs involving 6,386 overweight people who participated in programs and 5,467 who received the usual care. The study was published July 3 in The Annals of Internal Medicine.

Counseling-based weight-loss programs - those led by dietitians, nurses or doctors - produced an average weight loss of 6 percent of initial body weight, or about 11 pounds, at the end of one year. By the end of three years, participants had regained about half of that weight, and at the end of five years they had typically regained all of it.

The researchers acknowledge that the varied clinical and statistical techniques of the studies they examined make the exact magnitude of the treatment effect difficult to specify. Differences in counseling types, frequency, settings and the characteristics of the populations under study produced a wide range of results.

Still, the lead author, Dr. Michael L. Dansinger, a physician with Tufts-New England Medical Center in Boston, said: "When it comes to long-term weight loss, the health care system wants an A-plus grade, but based on this report, I'd give it a C minus. Primary care doctors should take a more active role in seeing patients more regularly for lifestyle management."