Several studies released in recent months demonstrate the dangers of being overweight. Some of this research offers a new perspective on that New Year's resolution you made about shedding a few pounds. It suggests that greater health benefits may come from making lifestyle choices for fitness rather than from aiming strictly at weight loss.
A study recently published in the Journal of the American Medical Association notes that overweight and obese adults face dramatically increased risk for diabetes and high blood pressure. A New England Journal of Medicine study of more than a million adults reports that the highest levels of obesity increase cancer deaths by 40 to 80 percent.
Additionally, a recent review of six major studies on the risks of overweight published in the Journal of the American Medical Association adds to the concern. It notes that more than 80 percent of deaths attributed to overweight occurred with a body mass index (BMI) of 30 or more. BMI is a way physicians and researchers express weight in relation to height. A BMI of 30 corresponds to a weight of 180 pounds for someone 5'5" tall, or 207 pounds for someone 5'10". The New England Journal of Medicine study found lowest mortality rates in persons with a BMI of about 21 to 26 (for someone 5'5", about 126 to 156 pounds).
Some researchers, however, question how much risk is really due to weight itself. Studies show that the lowest death rates are seen in people with the highest fitness levels, regardless of weight. Studies from the famous Cooper Institute show that those who are fit and overweight are at less risk than those who are "normal" weight but unfit. This definitely holds true for heart disease and may even be true for cancer. These studies also affirm that risk of diabetes and high blood pressure is clearly fitness-related.
So is it the weight or the lifestyle supporting the weight that's the real risk? If someone is overweight, but exercises regularly and eats a balanced, low-fat diet in appropriate portions, is he or she really at increased risk? Research shows that there are certain hormonal and physical effects that seem directly related to weight itself. Loss of 15 to 20 pounds, however, can generally lower health risks significantly, even though someone may still be well above what we call "normal" weight. A study in the Journal of the American Dietetic Association reports that overweight women who lost just one to nineteen pounds decreased death rates by 20 percent (including almost a 40 percent drop in cancer mortality).
Some people push furiously to reach recommended weight goals, believing that any means necessary are justified. Their meals become nutritionally unbalanced. Their calorie levels drop so low that muscle tissue is lost and metabolic rate slows. They lose interest in exercising. As a result, they undermine their health, and weight loss will most likely be temporary.
Those who lose weight but remain unfit generally achieve little improvement in health status. The smarter move, therefore, is to set lifestyle-related, rather than weight-based goals. Regular physical activity, along with a low-fat, mostly plant-based diet and appropriate portions will certainly leave you healthier, even though your "normal" weight may remain beyond recommended levels. If your excess weight is due to poor habits, then as you create a new lifestyle, your weight will most likely decrease as well.
Karen Collins, M.S., R.D.,C.D.N.
AICR
