More than half a million people were expected to die of cancer this past year, according to statistics released by the American Cancer Society. This widespread condition is the second leading cause of death in America, second only to heart disease, and it is responsible for about 25 percent of deaths annually.

Cancer is a condition characterized by abnormal cell growth. If the cells are allowed to continue growing and spreading unchecked, the endless replication leads to death. Currently, the average five-year rate of survival is above sixty percent. Of all types, the greatest killer is lung cancer. It is also the easiest to prevent, as smoking cessation can decrease a person's risk of contracting it.

While medical research has sought the cause of this family of deadly diseases for many decades, results of many studies reveal that they are the result of numerous, interrelated factors. Genetics, for example, plays a role in the predictability of many types of the disease, but it certainly does not explain the entire range of causes. In other words, cancer statistics are difficult to interpret.

Some lifestyle choices are known to have impact on longevity. For example, diets that are high in saturated fats are likely to result in heart disease, hypertension and some forms of cancer. Another factor whose benefits have been uncovered is a high activity level. People who exercise regularly appear to have a decreased risk of heart disease and, again, several specific forms of cancer.

Clearly, if you choose to eat a diet low in saturated fat, make fruits, vegetables and fiber a part of your daily nutrition, and exercise vigorously several times a week, your likelihood of being obese is very low. Not surprisingly, new studies in this decade are showing that people who are obese appear to have a greater likelihood of developing a number of specific types of cancerous conditions.

Studies on disease and mortality reveal some correlations that have surprised researchers and, often, factors that they were not initially designed to pinpoint. Conversely, some rather intuitive correlations cannot be successfully derived from the findings of research. For example, while some studies show that men who exercise regularly are at decreased risk for prostate cancer, one cannot immediately conclude that men who are obese are at greater risk. Common sense tells us that obese men are among those who are not exercising regularly, but statisticians are cautious about overstating the findings of research.

Obesity statistics are interwoven with cancer statistics in some complex and confusing ways. We know that people who are fit and trim and eat healthful foods appear less likely to contract diseases, but we also know of many exceptions.

Risk factors are not causes. They are simply factors that occur in parallel. One may or may not cause the other. In fact, the factors may co-exist because of an unknown third factor.

Medical research has determined with reasonable certainty that obesity is a risk factor for cancers of the colon, breast, endometrium (lining of the uterus), kidney, and esophagus. Because some studies show a decreased risk for cancers of the cervix, gall bladder, prostate, and thyroid in people with low fat diets and/or a higher level of physical activity, an obesity link to these forms of the disease is also suspected. Additional research is needed to confirm these links, but the national health agenda is increasingly focused on promoting healthy eating. Our nation's medical community has declared war on obesity and its causes.

In insulin resistance the body's cells are unable to respond adequately to the blood-sugar regulating hormone insulin resulting in an increased buildup of insulin and glucose in the blood stream. Insulin resistance is often a precursor to Type 2 diabetes, and one of the causes of obesity, heart disease, stroke and other conditions. Insulin is known to stimulate cell proliferation, so an overproduction or high concentration of the hormone may be partially responsible for cancer development. Insulin resistance has been associated with cancers of the colon and rectum, breast, and pancreas.

Defining Obesity Current definitions of obesity rely on a measure called the Body Mass Index or BMI. To calculate your BMI, visit Obesity Focused. A person with a body mass index exceeding 30 is considered obese, and someone with a BMI of 40 or more has morbid obesity. Morbid obesity refers to a dangerous condition in which the sufferer is at risk of physical disability and a severely impaired quality of life.

 

Statistics from the Centers for Disease Control and Prevention estimate that 61 percent of all Americans are overweight or obese. Most Americans, by now, are aware of the better known health risks associated with weight gain, such as cardiovascular disease and diabetes. The results of a recent survey by the American Institute for Cancer Research (AICR) show that only about one in four individuals knew that obesity was also a cancer risk.

According to the AICR, obesity increases the likelihood of developing the following cancers by 25 to 33 percent:

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