Healthy living
Body matters
Prevent type 2 diabetes
Recent research indicates that diet and exercise could reduce your risk of developing type 2 diabetes
Type 2 diabetes is strongly linked to age and obesity, both factors on the increase in our ageing, well fed and sedentary society. It is one of the leading causes of premature death and is known to affect around 2.2 million Britons. A further three-quarters of a million may have the disease without knowing it.
However, two new studies examining the preventive effect of weightloss in at-risk individuals suggest that making changes to your lifestyle could reduce your risk of developing the disease.
A year-long Washington University study, published in the American Journal of Clinical Nutrition, tracked the progress of 46 people aged between 50 and 60, with body mass indexes between 23 and 30, which while not obese are overweight or on the high side of normal.
To test whether diet or exercise is more effective at promoting weightloss and reducing the risk of developing diabetes, the participants were divided into three groups, with 18 each in the diet and exercise groups and 10 in the control group, who made no changes to their lifestyle.
All participants had their insulin action and glucose tolerance, both of which are indicators of diabetes, measured at the beginning and end of the study. In addition, their weight, body composition and energy intake were measured at the beginning of the study and at one, three, six, nine and 12-month intervals.
Those who cut calories had weekly meetings with a dietician who helped them to reduce portion sizes and go for lower calorie choices. Their goal was to reduce their calorie intake by 16 percent in the first three months and by 20 percent for the next nine.
Exercisers, who had the goal of burning 16 percent more calories for the first three months, increasing to 20 percent for the next nine months, had weekly meetings with an exercise trainer and had open access to a fitness centre. They exercised for between an hour and 90 minutes a day and tracked their progress on a heart rate monitor that recorded calories they had burned.
While those in the control group could request general advice on eating a healthy diet and free passes to a yoga class, few did, says lead author Edward Weiss, Ph.D.
Glucose tolerance and insulin levels improved at about the same levels in both the dieters and exercisers and they also lost weight. Those in the control group didn't lose weight or experience changes to their glucose tolerance or insulin levels.
"Both diet and exercise provide profound benefits to reduce the risk of diabetes. Both those who restrict calories and those who exercise benefit from weight loss," said Weiss.
"We thought exercise probably would produce greater benefits. But both of these are providing beneficial health improvements."
The second study, which appeared in the Lancet, showed that intensive diet and exercise counselling for people with impaired glucose tolerance can result in ongoing lifestyle changes that reduce the likelihood of type 2 diabetes.
Around 50 percent of people with impaired glucose tolerance will develop diabetes within 10 years, if nothing is done to prevent it.
In the Finnish Diabetes Prevention Study (FDPS), overweight, middle-aged people with impaired glucose tolerance were divided into two groups - one which made no changes to their lifestyle - and another which was given detailed, individual counselling on weight loss, how to decrease fat intake and increase fibre intake and the benefits of being physically active for at least 30 minutes a day.
After four years of active counselling, this group managed to cut their relative risk of type 2 diabetes by 58 percent compared with the control group.
Perhaps more surprisingly, an extended follow up to the FDPS study found that the educational benefits meant patients continued to make healthy lifestyle choices three years after the counselling finished. Their healthy choices added up to a 36 percent reduction in relative risk, thanks to weight loss, reduced intake of total and saturated fat, and being more active and upping their intake of dietary fibre.
Information on this site is for interest only and is not a substitute for professional medical advice. You should consult your own doctor about any specific health concerns.
