Counterpoint: Evidence-Based Prevention of Type 2 Diabetes: The Power of Lifestyle Management

Abstract

The need to prevent type 2 diabetes was recognized as early as the 1920s (1), but surprisingly little was done to apply preventive measures against this disease in subsequent decades (2,3). One of the main problems was the lack of evidence based on well-conducted studies. There were several clinical trials, but they were usually grossly underpowered, had flaws in design and conduct, and most used antidiabetes drugs as the intervention (3). Luckily, firm positive results from several randomized controlled trials (4–10) using lifestyle intervention have become available during recent years. Also, several properly designed and conducted trials using antidiabetes drugs in individuals at high risk, i.e., with intermediate hyperglycemia, have reported favorable results (8,10–14). The bottom line is that these recent trials have unequivocally demonstrated that it is possible to reduce the rate of progression to type 2 diabetes in high-risk individuals with intermediate hyperglycemia. The Swedish Malmo feasibility study (5) used increased physical exercise and weight control as major intervention strategies to prevent or delay type 2 diabetes in men with impaired glucose tolerance (IGT). Men who received intervention had less than half the risk of developing diabetes in 6 years compared with those who decided not to participate in the diet-exercise program. In the Chinese Da Qing Study (6), people with IGT were randomized by clinic into one of the four groups: exercise only, diet only, diet plus exercise, and a control group. The cumulative incidence of type 2 diabetes during 6 years was significantly lower in the three intervention groups compared with the control group (41% in the exercise group, 44% in the diet group, 46% in the diet plus exercise group, and 68% in the control group) and remained significant even after adjusting for differences in baseline BMI …