Yo-Yo Dieters No Different in Future Weight Loss
Every year, an estimated 10 to 40 percent of overweight women lose and then regain that weight, an exhausting cycle of yo-yo dieting that researchers have hypothesized may harm women metabolism and their ability to lose weight over the long term.
Not so, finds a new study published online in the journal Metabolism.
The study looked at the effects of a healthy weight loss program among 439 overweight and sedentary post-menopausal women. Some of the women had a longtime history of yo-yo dieting – referred to by researchers as weight cycling – and others did not. The women were randomly assigned to one of four groups: one group ate fewer calories; a second group exercised; a third group ate fewer calories and exercised; the last group served as the control, receiving no intervention.
About 20 percent of the women had gone through at least three bouts of weight cycling, having lost 20 or more pounds then gaining it back each time. Another 25 percent of the women had lost and regained at least 10 pounds multiple times. On average, the weight cyclers were about 20 pounds heavier when they entered the study compared to the women who had not yo-yo dieted.
After one year, there was no difference among the weight cyclers and non-weight cyclers when it came to weight loss and program participation. The women who dieted-only and dieted-with-exercise lost an average of 10 percent of their starting weight. The women in these groups showed no difference from the non-cyclers with regard to percentage of body fat lost and lean muscle mass gained. Blood pressure, insulin sensitivity, and levels of hormones such as leptin and adiponectin also did not differ significantly among the cyclers and non-weight cyclers.
Source: Mason C, Foster-Schubert KE, Imayama I, Xiao L, Kong A, Campbell KL, Duggan CR, Wang CY, Alfano CM, Ulrich CM, Blackburn GL, McTiernan A. “History of weight cycling does not impede future weight loss or metabolic improvements in postmenopausal women.” Metabolism. 2012 Aug 13. [Epub ahead of print]