In 2002, the Diabetes Prevention Program Research Group published this study in the New England Journal of Medicine:Reduction In The Incidence Of Type 2 Diabetes With Lifestyle Intervention Or Metformin
Researchers found that:
"Type 2 diabetes can be prevented or delayed in persons at high risk for the disease [by following] a lifestyle-modification program with the goals of at least a 7 percent weight loss and at least 150 minutes of physical activity per week."*The study compared these lifestyle changes with the drug metformin. The researchers found "lifestyle intervention was more effective than metformin," reducing the incidence of diabetes by 58% compared with 31% in the metformin group. (Comparisons were made against a placebo group.)
* Participants were considered at high risk if they had either impaired glucose tolerance (IGT), defined by a glucose level of 140-199 mg/dl, 2 hours after a 75 g glucose challenge, or impaired fasting glucose (IFG), defined by a fasting glucose level of 100-125 mg/dl, or both.
Fast forward to November 2009 and this study which appeared in the Lancet:
10-Year Follow-Up Of Diabetes Incidence And Weight Loss In The Diabetes Prevention Program Outcomes Study
Researchers investigated the long-term effect of the original interventions - lifestyle changes or metformin - in the original participants. Although differences in incidence rates lessened between the groups, "the cumulative incidence of diabetes remained lowest in the lifestyle group." In the 10 years since the original study, diabetes incidence was reduced by 34% in the lifestyle group compared to 18% in the metformin group. (Comparisons were made against a placebo group.)
What Constituted Lifestyle Change
The original study set forth the following goals for their lifestyle-modification group:
- To achieve and maintain a weight reduction of at least 7% of initial body weight through a healthy low-calorie, low-fat diet
- To engage in physical activity of moderate intensity, such as brisk walking, for at least 150 minutes per week.
"A 16-lesson curriculum covering diet, exercise, and behavior modification was designed to help the participants achieve these goals. The curriculum, taught by case managers on a one-to-one basis during the first 24 weeks after enrollment, was flexible, culturally sensitive, and individualized. Subsequent individual sessions (usually monthly) and group sessions with the case managers were designed to reinforce the behavioral changes."Lifestyle changes, including weight loss, exercise, and a healthful diet, have repeatedly been shown to be effective at delaying the onset of diabetes.
