WEDNESDAY, May 2 (HealthScout) -- A few changes in lifestyle can go a long way for people at risk for diabetes.
The changes that health authorities have been recommending for years -- fewer calories, less fat in the diet, moderate exercise -- can reduce the risk of developing adult-onset diabetes by more than half for high-risk individuals, a Finnish study finds.
"This is not the first study that shows that changing lifestyle has the potential of delaying the onset of disease," says Dr. P. Antonio Tataranni of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). "But it is the most convincing study we have. It was very well designed, and as far as we can tell, there are no more lingering doubts that the concept has been proven."
The three-year study by researchers at the National Public Health Institute in Helsinki involved more than 500 middle-aged and overweight individuals. Participants were selected by screening high-risk groups, such as close relatives of Type II diabetes patients.
Half the participants were given general information about good diet and exercise and then left on their own. The other half got detailed advice on ways to lose at least 5 percent of their weight and to reduce intake of fat and increase intake of fiber. They also met periodically with nutritionists and had supervised exercise sessions for at least 30 days.
"During the trial, the risk of diabetes was reduced by 58 percent in the intervention group," the researchers report in the May 3 issue of the New England Journal of Medicine. "The reduction in the incidence of diabetes was directly associated with changes in lifestyle."
That percentage might be underestimated for two reasons, the researchers say. First, not all people in the intervention group followed the recommendations about diet and exercise. "Second, for ethical reasons, all subjects assigned to the control group also received general health advice at base line and at annual follow-up visits and may have benefited from this advice," they say.
The most remarkable aspect of the study is that "it showed that very modest changes in weight and activity had a big effect," says Dr. Robert Sherwin, professor of medicine at Yale University School of Medicine and president of the American Diabetes Association.
And Sherwin says the results almost certainly apply to prevention of cardiovascular disease. "Heart disease and diabetes are not that far apart. A lot of people who are prone to diabetes are prone to heart disease. It is all part of the same problem," he says.
The findings should be helpful to anyone at risk of diabetes, a large and heterogeneous group, Sherwin says. It includes anyone with a family history of diabetes, people with high blood pressure, women who have large babies or who have mild diabetes during pregnancy and members of "more or less every minority group in this country," he says.
Those people should consider having glucose tolerance tests to assess their ability to handle sugar, Sherwin says. "We're not sure we want everyone to have a glucose tolerance test, but for people who are not diabetic but have a high risk for diabetes, it can be advisable."
Everyone should follow the lifestyle guidelines recommended by organizations such as the American Diabetes Association and the American Heart Association, says Tataranni, who heads the NIDDK's Obesity, Diabetes and Energy Metabolism Unit in Phoenix. "A healthy lifestyle works," he says.
A U.S. study is testing the effect of lifestyle changes or drug treatment -- or both -- in preventing diabetes, Tataranni notes. More than 3,000 men and women with impaired glucose tolerance are enrolled in the Diabetes Prevention Program. Some are following the lifestyle rules while others are taking metformin, a diabetes drug. Results are expected next year.
What To Do
Enough said? For years, doctors have been urging people at risk for diabetes to maintain a healthy lifestyle. This study shows how much it pays off.
Eating less fat, avoiding obesity, engaging in moderate exercise (a 30-minute walk every day will do) can help significantly.
Information about Type II diabetes is available from the NIDDK . Information on a healthy lifestyle is available from the American Heart Association and the American Diabetes Association.
