Obese people have an overall mortality rate almost twice that of non-obese people. They are more than three times as likely to develop diabetes. Obesity is associated with unhealthy cholesterol levels and impaired heart function. It is estimated that if all Americans had a healthy body composition, the incidence of coronary heart disease would drop by 25%. Other health risks associated with obesity include hypertension, many kinds of cancer, impaired immune function, gallbladder and kidney diseases, and bone and joint disorders. These risks from obesity increase with its severity, and they are much more likely to occur in people who are more than twice their desirable body weight.
The effects of obesity on health were further clarified by the Nurses’ Health Study, in which Harvard researchers have followed more than 120,000 women for over 16 years. It found that even mildly overweight women had an 80% increased risk of developing coronary heart disease compared to leaner women. This study also confirmed that to reduce the risk of dying prematurely of any cause, maintaining a desirable body weight is important.
The distribution of body fat is also an important indicator of future health. People who tend to gain weight in the abdominal area have a risk of coronary heart disease, high blood pressure, diabetes, and stroke twice as high as those who tend to gain weight in the hip area. The reason for this increased risk is not entirely clear, but it appears that fat in the abdomen is more easily mobilized and sent into the bloodstream, increasing disease-related blood fat levels.
In addition to risking physical health, obesity can impair psychological health. Being perceived as fat can be the source of ridicule, ostracism, and sometimes discrimination from others; it can contribute to psychological problems such as depression and low self-esteem. For some, the stigma associated with obesity can give rise to a negative body image, body dissatisfaction, and eating disorders such as anorexia and bulimia.
Overweight and obesity are not associated with or caused by a single variable. Rather, they are multi-factorial in nature. The research on overweight and obesity provides convincing evidence that they result from a complex of interacting traits, acquired conditions and lifestyle variables that implicate various environmental, behavioral, psychological, physiological, social and genetic factors.
Some risk factors are described in the literature as being independent because they have the potential to bring about overweight or obesity single-handedly. However, risk factors and causes can and most often interact and work together with one another to create a greater likelihood of becoming overweight or obese and have a greater deleterious impact on health. It stands to reason that the more risk factors and causes an individual possesses for obesity the