Weight cycling and the risk of developing type 2 diabetes among adult women in the United States

Objective: To assess the role of weight cycling independent of BMI and weight change in predicting the risk of developing type 2 diabetes. Research Methods and Procedures: A six-year follow-up of 46,634 young and middle-aged women in the Nurses' Health Study 11 was conducted. Women who had intentionally lost greater than or equal to20 lbs at least three times between 1989 and 1993 were classified as severe weight cyclers. Women who had intentionally lost ! 10 lbs at least three times were classified as mild weight cyclers. The outcome was physician-diagnosed type 2 diabetes. Results: Between 1989 and 1993, similar to20% of the women were mild weight cyclers, and 1.6% were severe weight cyclers. BMI in 1993 was positively associated with weight-cycling status (p < 0.001). During 6 years of follow-up (1993 to 1999), 418 incident cases of type 2 diabetes were documented. BMI in 1993 had a strong association with the risk of developing diabetes. Compared with women with a BMI between 17 and 22 kg/m(2), those with a BMI between 25 and 29.9 kg/m(2) were approximately seven times more likely to develop diabetes, and those with a BMI greater than or equal to35 kg /m(2) were 63 times more likely to be diagnosed with type 2 diabetes. After adjustment for BMI, neither mild (relative risk = 1.11, 95% confidence interval, 0.89 to 1.37) nor severe (relative risk = 1.39, 95% confidence interval, 0.90 to 2.13) weight cycling predicted risk of diabetes. Discussion: Weight cycling was strongly associated with BMI, but it was not independently predictive of developing type 2 diabetes.