Other Contributing Risk Factors for Health

Obesity

Obesity is not conducive to increased longevity because it is a strain on the heart and a precursor for many of the modifiable risk factors that promote cardiovascular disease. The national institutes of health (NIH) has summarized the data that were collected before 1985 on the relationship between obesity and health. The results indicated that obesity is highly related to increased sickness and death. Studies since 1985 have confirmed the NIH results. This section concentrates on the relationship between obesity and cardiovascular disease.

The health risks associated with obesity were summarized by the national task force on the prevention and treatment of obesity. Some of the conclusions generated by their analysis of all studies completed before 1994 are as follows:

1. There is a strong positive association between obesity and abnormal blood fats hypertension, and excessive production and secretion of insulin by the pancreas. These factors lead to the increased likelihood of coronary artery disease and type II diabetes mellitus.

2. Obesity increases the risk for certain types of cancer, degenerative joint disease, sleep apnea, gout, and gallbladder disease.

3. The relative risk for the conditions mentioned previously increases markedly in young adults. Obesity in adolescent boys was associated with increased mortality as long as 50 years later regardless of body weight status as adults. Of young people ages 12 to 19, 21 % are overweight. 32 teens spend approximately 22 hours per week watching television and playing video and computer games.

4. The economic cost attributed to obesity related illness is estimated to be in excess of $39 billion annually.

Diabetes Mellitus

Diabetes mellitus is a metabolic disorder in which the body cannot make use of sugar as a fuel. The hormone insulin must be produced and secreted into the bloodstream so that blood sugar can be transported into the cells. The cells have receptor sites to which insulin attaches, making the cell amenable to the entrance of sugar.

In type i diabetes, no insulin is produced, thus it must be injected daily. Type 1, referred to as insulin dependent diabetes mellitus (IDDM), usually occurs early in life. Type II, or non insulin dependent diabetes mellitus (NIDDM), occurs in middle aged, overweight, sedentary adults. Excessive weight is a factor because it increases cellular resistance to insulin so that it takes more insulin than normal to effect the passage of sugar from the blood to the cells. On the other hand, exercise decreases insulin resistance so that cellular membranes become more permeable to sugar. About 90% of all diabetes mellitus is of the type II variety.

Diabetes mellitus has numerous long range complications. These primarily involve degenerative disorders of the blood vessels and nerves. Diabetics who die prematurely are usually the victims of cardiovascular lesions and accelerated atherosclerosis. The incidence of heart attacks and strokes is higher among diabetics than nondiabetics. In fact, diabetes increases the risk of coronary artery disease by two to three times the normal rate in men and three to seven times in women.

The arteries supplying the kidneys, eyes, and legs are particularly susceptible to atherosclerosis. Kidney failure is one of the long term complications of diabetes. Diabetes is also the second leading cause of blindness in the united states. Impaired delivery of blood to the legs may lead to gangrene, necessitating amputation of the affected tissues. In addition to circulatory problems, degenerative lesions in the nervous system lead to multiple neuropathies that result in dysfunction of the brain, spinal cord, and peripheral nerves. Unfortunately, medical science has been unable to identify the biological mechanisms responsible for these long term vascular and neural complications. However, these complications can be mitigated by leading a balanced, well regulated life, thereby keeping diabetes under control. Control includes dietary manipulation, exercise, weight control, rest, and medication if needed.

The landmark physician's health study was the first major effort to show that exercise reduced the risk of developing type II diabetes. 33 The physicians who exercised vigorously five or more times per week had a 42% reduction in NIDDM compared with those who exercised less than one time per week. The reduction in risk was particularly pronounced among those at the greatest risk the obese. The researchers concluded that at least 24% of all cases of NIDDM were related to sedentary living.