The National Center for Health Statistics found that, in the past decade, the proportion of U.S. adults who are overweight increased by eight percent to 33 percent. Other studies support these findings. In 1985-86, the average weight was 161 pounds for the same age group. After all, fat has nine calories per gram while protein and carbohydrates only have four each. The answer may not be a simple one.
Experts believe a number of factors contribute to the increase in body weight.
The continuing physical inactivity of Americans has been cited by numerous researchers as a major factor. Only 40 percent of Americans exercise on a regular basis. In addition, researchers point to such symptoms of a sedentary lifestyle as a 10 percent decline in sports participation from 1985-90, and a decline in manufacturing jobs, which means fewer people move around at work. Other factors include a decrease in physical activity caused by television, a continuing increase in the usage of automobiles, and a decrease in physical education classes in schools. And these symptoms may be here to stay.