Type 2 diabetes: prevention can be a few steps away

More than a million people will be diagnosed with type 2 diabetes this year. The overwhelming majority will be sedentary, overweight adults-a group slow to change their eating and exercise habits in spite of the potentially dire consequences of the disease. But a new study in The New England Journal of Medicine reports that even small lifestyle changes-a few less calories and a little more exercise-can considerably reduce a person's chances of developing this form of diabetes.

The proof is in the eating and exercise

Finnish researchers recruited more than 500 middle-aged, overweight men and women with an impaired ability to metabolize blood sugar-prime candidates for the development of type 2 diabetes. They were divided into two groups-an intervention group and a control group. The intervention group received intensive diet and exercise training, with these goals:

• Reduce body weight by 5%
• Reduce intake of fat to 30% of total calories
• Reduce saturated fat to 10% of total calories
• Increase fiber intake to 15 grams for every 1000 calories consumed
• Exercise at least 30 minutes each day

The control group received only printed information on diet and exercise. Researchers assessed weight and blood sugar levels several times during the study.

At the end of one year, those in the intervention group lost an average 4.2 kg (about 9 lbs), compared with an average weight loss of 0.8 kg (almost 2 lbs) of those in the control group. Progress was not as pronounced during the second year of the study, but those receiving diet counseling still managed to weigh in at an average 3.5 kg (almost 8 lbs) less than their starting weight, while those in the control group stayed the same. Those who lost weight trimmed their waistlines and improved their blood sugar measurements.

Small changes made a big difference

Four years into the study, 11% of those in the intervention group had developed diabetes, compared with 23% in the control group. The researchers estimate that the diet and exercise changes made by those in the intervention group reduced their risk of type 2 diabetes by 58%.

Of note is that those who exercised at least 4 hours per week, even if they were not able to meet the weight loss goal, fared better than those who stayed sedentary. And any kind of moderate exercise-walking, weight training, yard work-counted toward the exercise goal.

Predictably, those who were most successful in meeting both their diet and exercise goals were the ones most likely to see substantial health benefits. During the course of the study, nobody, regardless of treatment group, developed diabetes as long as four of the five diet and exercise goals were met. On the other hand, 38% of those in the intervention group and 31% of those in the control group who met none of the study's goals developed diabetes within 4 years.

Good health habits pay off

The authors acknowledge that it is hard to change eating and exercise habits, and that success is usually measured in small increments. But, for those "on the bubble" for type 2 diabetes-overweight, sedentary, middle-aged adults with abnormal blood sugar levels-this study suggests that even small changes for the better can have a significant effect on their health.