Lifestyle changes seem to keep diabetes at bay for a decade.
THE QUESTION In the short term, eating more healthfully and losing weight have been shown to be effective at preventing diabetes in people considered at risk for the disease. But does the effect last?
THIS STUDY analyzed long-term data on 2,766 adults who had participated in a three-year study that had randomly assigned them to participate in an intensive program of lifestyle changes, to take the diabetes drug metformin or to take a placebo. As a result, the risk for diabetes was reduced by 58 percent among those who made lifestyle changes -- eating foods with less fat and fewer calories and exercising 150 minutes a week -- and by 31 percent among those who took metformin, compared with the placebo group. In a re-analysis 10 years after the original study began, people who had made lifestyle changes had regained some of the 15 pounds, on average, they had lost initially, but they still had lost an average of 4.4 pounds; those taking metformin maintained a weight loss of 5.5 pounds, on average. Diabetes risk for the lifestyle-change group was reduced by 34 percent (and 18 percent for the metformin group), compared with those who took the placebo. Among people age 60 and older, risk was cut by about half. The onset of diabetes was delayed by about four years for people who had made lifestyle changes and two years for those who had taken metformin.
WHO MAY BE AFFECTED? People considered likely to develop diabetes. Risk factors include having a family history of the disease, being overweight and being physically inactive, all of which can contribute to having higher-than-normal levels of sugar (glucose) in the blood. The body needs insulin to use glucose for energy, but in people with Type 2 diabetes, the body does not produce enough insulin or cannot use it properly.
CAVEATS After the initial study ended, all participants were given counseling on lifestyle changes, which might have affected results of the long-term analysis.
FIND THIS STUDY Oct. 29 online issue of the Lancet.
-- Linda Searing
The research described in Quick Study comes from credible, peer-reviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician.