Preventing Diabetes Through Diet and Exercise
Why should I be concerned about diabetes?
In the United States, type 2 diabetes (formerly called adult-onset diabetes) is reaching epidemic proportions. It has even reached an alarming number of teenagers and young adults, a group that seemed practically immune to the disease just a few decades ago. There's no mystery behind this increase in incidence. Scientists don't need to explore various theories or perform experiments to understand the problem. The reason for our national struggle with diabetes is as obvious as our lifestyle. In general, our diets, activity levels, and waistlines have all taken an unhealthy turn, and type 2 diabetes is the price many of us end up paying.
The good news is that neither your lifestyle nor your risk of developing diabetes is written in stone. You can buck the national trends by exercising regularly, eating a well-balanced diet, and watching your weight.
In fact, people at risk of type 2 diabetes can more than halve their risk of developing the disease by exercising about half an hour a day and adopting a low-fat diet, according to a study conducted by the National Institutes of Health. Participants who did about 30 minutes of walking or other low-intensity exercise a day, coupled with a low-fat diet, lost an an average of 5 to 7 percent of their body weight and cut their chances of developing type 2 diabetes by 58 percent. Those treated with the diabetes drug metformin -- but who didn't make the lifestyle changes -- cut their risk by only 31 percent.
Here's a closer look at how healthy living can protect you from the disease that kills more Americans each year than prostate cancer and breast cancer combined.
- Exercise regularly. Physical activity works against type 2 diabetes at its source. The disease gets its start when muscle cells lose their sensitivity to insulin, the pancreatic hormone that controls levels of sugar in the blood. For some reason, your muscle cells are much less likely to shun insulin if you keep them fit through regular exercise. If you are at high risk for diabetes, experts recommend increasing your level of exercise to at least 150 minutes of moderate activity (such as walking) per week.
A study at the Cooper Institute for Aerobics Research in Dallas shows that staying fit may be the most crucial measure for avoiding type 2 diabetes. The researchers put 8,633 men (whose average age was 43) through a treadmill test and then screened them for diabetes six years later. The men who'd scored poorly on the fitness test were almost four times more likely than those who'd done well to show signs of the disease. Indeed, the fitness scores turned out to be the best predictor of diabetes, more telling than age, obesity, high blood pressure, or even a family history of the disease.
If you're sedentary now, find ways to incorporate more physical activity into your everyday life. Start gently, but work toward getting at least 30 minutes a day of moderate exercise.
Eat a healthy, balanced diet. The typical American diet seems tailor-made for promoting type 2 diabetes. According to two studies from the Harvard School of Public Health, men and women who eat large amounts of simple sugars but little fiber are more than twice as likely to develop the disease as people following high-fiber, low-sugar diets. And several studies have found that people with impaired glucose (sugar) tolerance -- an early warning sign of diabetes -- are much more likely to become diabetic if they eat large amounts of saturated fat. You can stay on the right side of these findings by sticking with a low-fat diet that's rich in fruits, vegetables, and whole grains.
- Avoid excess weight. It stands to reason that obese people are particularly prone to type 2 diabetes. After all, extra pounds are often a sign that a person isn't exercising enough or making healthful food choices. Yet this point goes beyond the obvious: Recent studies have found that obesity plays an active role in the onset of diabetes. Extra body fat, especially around the midsection, can spur on the disease by making cells less responsive to insulin and by slowing down production of the hormone. If you can stay trim through diet and exercise, you'll be fighting diabetes on three fronts.
Doctors are now being recruited to counsel patients who are obese. According to one survey in the Annals of Internal Medicine, only 42 percent of overweight adults have been told by their doctors or healthcare workers to lose weight.
That's the reason why government health officials at the US Preventive Services Task Force recommend that doctors assess patients to determine their BMI. If they're obese, they should make weight loss counseling part of their talks. If you are at high risk for diabetes, experts recommend that you lose at least 7 percent of your body weight.
- Check with your doctor. If you have special reasons to be concerned about diabetes, be sure to discuss the matter with your doctor. In particular, if you've been exercising regularly and eating right for months but you're still significantly overweight, it's a good idea to get a physical exam.
Ask your doctor whether you might be insulin resistant or have another condition linked to diabetes. Now a simple blood test can detect diabetes (or a tendency toward it) and the test can often be done in the doctor's office. Detecting such a condition early on gives you a great opportunity to resolve it and keep diabetes at bay.
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