In addition to there being plenty of food in our environment, Western society has evolved to the point where physical activity is a minimal part of our daily lives. Fewer jobs require physical exertion, and we rely more on automobiles and public transportation than on our legs to get around. In fact, over 75% of all trips in the United States that were less than one mile were made by automobile in 1995.
Even if we wanted to walk more, there are plenty of reasons not to. People tend to work long hours these days, and there seems to be little time left to take care of ourselves and our families. When we do have leisure time, there are many claims on our attention, such as television and computers. The conveniences and temptations of modern life may simply be too much competition for taking a walk to the store, riding a bike, pushing a lawnmower, or washing the car by hand. But if our lifestyle is contributing to the rising rates of obesity, then reversing the trend almost certainly means changing our lifestyle. Are we willing to do that?
Although there is no cure for obesity, there are ways to treat and manage it, including dietary changes, increased physical activity, behavior therapy, and medication. Surgery is an option for the most obese individuals (BMI greater than 40 kg/m2 or BMI greater than 35 kg/m2 with risk factors).
Most people can expect to lose 10% to 15% of their body weight through diet, exercise, and behavior change techniques (although some lose more), and a loss of even 10% of body weight will significantly reduce weight-related health risks. However, 95% of people who lose weight regain all of it within five years, and some gain back more than they lost in the first place. How much weight is regained depends a lot on diet and physical activity. Research shows that people who lose weight but don’t begin or continue a program of physical activity regain most if not all of their weight in less than nine months. Those who are active tend to maintain their weight loss.
Many scientists believe that obesity begins sometime in the early stages of life, so working with children and their parents to prevent obesity or treat it early makes a lot of sense, particularly since it is so hard for adults to lose weight and keep it off. The limited amount of research that has been done in this area shows encouraging results, but the research is recent, and long-term results are not yet available.
In 1980, 5.8 million Americans had diabetes. Today, the number of diagnosed cases is 10.3 million, a whopping increase of 77%. By 2020, if the increase in diabetes continues at the current rate, 18.2 million Americans will have it.
The risk of developing diabetes increases as BMI increases. A BMI over 22 kg/m2 is associated with an increased risk of diabetes, and the risk jumps approximately 25% for every unit above 22 kg/m2. The development of Type 2 diabetes is associated with weight gain after age 18, and it was recently estimated that 27% of new cases of diabetes were attributable to weight gain in adulthood of 11 or more pounds. Among persons who have been diagnosed with Type 2 diabetes, 67% have a BMI greater than or equal to 27 kg/m2, and 46% have a BMI greater than or equal to 30 kg/m2.
Almost 800,000 new cases of diabetes are diagnosed each year in the United States. The total yearly cost of treatment and prevention exceeds $98 billion dollars, with approximately $44 billion dollars spent on direct medical costs. A troubling feature of these numbers is that while Type 2 diabetes was once considered a disease of adults 50 years and older, approximately 25% of all new cases of Type 2 diabetes are diagnosed in teenagers.
It is widely believed that this new health crisis in youth is the result of inactivity, poor diet, obesity, and a genetic predisposition for diabetes. While there is no generally accepted definition of obesity as distinct from overweight in children and adolescents, the prevalence of overweight is increasing for children and adolescents in the United States, as is the level of physical inactivity.