Slimming Down: The Big Picture
The study was designed to test the effects of diet and/or exercise on body weight and composition but not specifically differences related to yo-yo dieting. "That limits a little what they can say," says Victoria Stevens, PhD, strategic director for laboratory sciences at the American Cancer Society. "Other than that, it’s a good study."
Some studies have linked weight cycling to an increased risk of death, but few of them distinguished intentional weight loss from weight loss due to illness. Stevens recently published a study of more than 100,000 men and women who were asked how many times they had intentionally lost and regained 10 pounds or more. After accounting for BMI and other risk factors, her research did not find that weight cycling was associated with an increased risk of death.
Stevens notes that the people in her study were born around the time of World War II, when childhood obesity wasn’t as big a problem as it is now. "They just got fatter as they got older," she says. Today, though, people start weight cycling as teenagers, and the timing could make a difference as far as risk of death, Stevens says. "I think that’s going to be a really important question to address."
So is it worth trying yet again to slim down?
"Women should keep trying," McTiernan says. "If nothing else, losing weight again gives you a period of time at a lower weight, which improves your health for however long you keep the weight off."
The study appears online in the journal Metabolism.