Obesity is epidemic in our country. Over 60% of the US population is overweight, 30% are obese. John Hopkins School of Public Health in a press release estimates that by the year 2015, 75% of adults will be overweight; 41% will be obese.
It has been found that obesity increases the risk of cancer death and that higher grade tumors (more aggressive tumors) are more common in those who are obese. Obesity has been especially associated with colon, breast and prostate cancers. Ovarian cancer studies have shown that ovarian cancer recurs sooner and that life expectancy is shorter in women who are obese. Weight gain following a breast cancer diagnosis greatly decreases a woman’s chances of surviving the disease.
Obesity is associated with insulin resistance. When our bodies become insulin resistant, we produce more insulin in an attempt to compensate. Higher levels of insulin and a substance called insulin-like growth factor are found in those who are obese. Insulin-like growth factor causes cells to reproduce and prevents cells from dying, which can contribute to cancerous growth. Vitamin D is also sequestered in fat cells. It is also thought that fat cells produce hormones or compounds that make cancer grow more aggressively.
Overall, research shows that increased weight is associated with increase cancer recurrence and decreased cancer survival…recurrence rates are doubled and there is a 60% increase in cancer death rate associated with obesity. The drug Tamoxifen, used to treat breast cancer, is less effective in those who are overweight.
A higher body mass index is associated with a higher cancer risk.
A healthy BMI is 18.5 to 24.9. A BMI of 25 or higher is considered overweight. A BMI of 30 is considered obese. You can calculate your BMI at this NIH link: Calculate your Body Mass Index