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WEIGHT LOSS CAN CUT RESISTANCE TO INSULIN

Question: I have recently been diagnosed as having type II diabetes and would like to know more about this disease. Could you discuss what causes type II diabetes, what are the health risks and how exercise helps? I read your column every week and will look forward to your answer.

Answer: According to the information in a release from the publication "Sports Science Exchange" (March 1992, the Gator- ade Sports Science Institute), about 14 million Americans have diabetes and about 80 percent of these Americans have the type II form.Type II diabetes is usually called "noninsulin dependent diabetes mellitus (NIDDM)" because it starts when the insulin sensitive tissues develop a resistance to the action of insulin. Since the tissue is insulin-resistant, the sugar (glucose) in the blood cannot get into the tissues, so the blood sugar levels go up. An increase in blood sugar levels causes the pancreas to secrete even more insulin to try to maintain normal sugar levels. Eventually, the cells that secrete insulin may "wear out" trying to secrete enough insulin, and then insulin must be supplied by injection.

No one knows exactly what causes this disease, but it probably involves defects in the insulin receptor and/or glucose transport mechanisms in the cell. Interestingly, about 80 percent of people with NIDDM are obese; and insulin resistance can be reduced with weight loss.

There are several major health risks related to NIDDM: blindness is 29 times more frequent, renal disease risk is increased 17 times, amputations occur five times more frequently, and cardiovascular disease is three times more common.

One of the main reasons exercise helps persons with NIDDM so much is that it decreases insulin resistance; people who exercise need less insulin. In one study, subjects who exercised for six weeks had a 35 percent increase in the amount of glucose in the blood, which decreases the negative effects of the glucose on the various tissues. Exercise also helps the weight loss process; and insulin resistance is improved with weight loss.

In addition to the advantages of exercise mentioned above, exercise has a positive effect on health that is not related to the sugar problems. For instance, research shows that non-diabetic exercisers have only half the risk for cardiovascular disease compared to non-exercisers. Because those with NIDDM have an increased risk for cardiovacular disease, a well-planned exercise program may make a major reduction in heart disease for this population.

Since the degree of control and the presence of certain problems associated with NIDDM can affect the specific recommendations for exercise, every diabetic should consult with his/her physician before beginning an exercise program. However, probably all diabetics should have a moderate, carefully controlled aerobic type of exercise program as part of the overall treatment of this disease.

Question: Is there anything new in the treatment of obesity? I have been trying to control my weight for almost my entire life and would like to do something that would really work. I enjoy your column. Keep up the good work.

Answer: Trying to control body weight is a challenge to those of us who have a problem. In 1983, some colleagues and I wrote the book "How to Lower Your Fat Thermostat" and basically suggested that people should be more concerned about the amount of fat and sugar in the diet than the total number of calories. We recommended increasing the amount of complex carbohydrates such as fruits, vegetables, beans and grains and avoiding diets that severely restricted the caloric intake. We also said that exercise was a key factor in losing weight and maintaining that loss.

I have read literally hundreds of studies relating to weight loss since that time, and I still think these guidelines are sound. The more I read and study about weight loss, the more I am convinced that programs must be realistic in terms of your long-term lifestyle to be successful. Very few of us will eat only 1,000 calories a day or exercise for three hours a day for the rest of our lives; nor will we be happy completely avoiding all desserts and snacks.

An interesting weight-loss study was done at the University of Minnesota with a group of women who averaged 175 pounds (about 20 to 40 percent over "ideal" weight). Half of the women were told to eat no more than 1,200 calories a day with a maximum of 40 grams of fat - about 30 percent of their caloric intake. They were told that they could eat up to 6 ounces of poultry, fish or red lean meat a day, so this group ate meals that were quite typical of most Americans, such as chicken with rice and turkey platters.

The other group was told to gradually lower their fat intake to just 20 grams per day, but were told to eat as much of foods high in complex carbohydrates such as fruits, vegetables and grain-based foods (rice, pasta and bread) as it took to feel satisfied. The type of meals by this group changed to more "plant-centered" entrees like spaghetti topped with herb-seasoned lentil and tomato sauce, black beans with rice and vegetarian chili.

Neither group followed the instructions perfectly, but the calorie-counters got down to 1,550 calories a day and the fat watchers lowered their fat to 37 grams. At the end of six months, the women in both groups lost about the same amount - an average of 8 to 10 pounds each. The important point was that the group that was not concerned with counting calories said that their food tasted better and they scored higher on a "quality of life" scale. In addition, six months after the study ended, the non-calorie restricted group had maintained their weight loss more successfully than the calorie-restricted group.

It is probably easier to follow a diet where, although the number of grams of fat is restricted, you can eat until your hunger is satisfied than a diet where you always feel a little hungry. Of course, you must also begin, and continue, a moderate exercise program if you want to be really successful.