Many parents view their children’s excess weight as an aesthetic issue. They worry their kids won’t be liked in school, won’t be picked in gym, and won’t be pursued by members of the opposite sex. According to the American Institute of Cancer Research, parents have a lot more than looks to be concerned about. New research shows that about 100,500 new cases of cancer are caused by obesity each year.

Obesity is known to cause many deleterious health effects but this study is one of the first to conclusively link specific cancers to excess body fat. And as the number of obese people increases in the population, so does the number of cancer patients! According to the study, 49% of endometrial cancer (about 20,700 cases per year), 35% of esophageal cancer (5,800 cases per year), 28% of pancreatic cancer (11,900 cases per year), 24% of kidney cancer (13,900 cases per year), 21% of gallbladder cancer (2,000) cases per year, 17% of breast cancer (33,000 cases per year), and 9% of colorectal cancer (13,200 cases per year) are due to obesity.

How does being overweight increase your risk of cancer? That depends on the type cancer. Experts believe that the increased estrogen found in overweight women leads to endometrial and breast cancer. Post-menopausal obese women have 1.5 times the risk of breast cancer than normal weight post-menopausal women. Before menopause, the ovaries are the primary source of estrogen. Fat tissue, however, also makes estrogen. Post-menopausal women, whose ovaries no longer make estrogen, tend to have lower estrogen levels. Obese women have estrogen levels that are 50-100% higher than normal weight women. It is believed that this increased level of estrogen causes rapid growth of estrogen-responsive breast tumors.

Obese women are not only more likely to get breast cancer, but they are more likely to die from it. Breast cancer is harder to detect in an obese woman and is usually diagnosed at a much later stage, leading to lower survival rates. Weight gain during adulthood is the most consistent and strongest predictor of breast cancer risk.

It is not clear why obese people have a higher risk of colon cancer than normal weight people. It may be that the high levels of insulin or insulin-related growth factors in the obese promote tumor development.

Gastro-esophageal acid disease (GERD), common in the obese, is the likely cause of the increased risk of esophageal cancer.

The reason for the link between other cancers and obesity is not known. The obese tend to have higher levels of many different hormones and growth factors that likely increase the risk of cancer.

What should we take from this study? The importance of preventing weight gain in the first place! Parents need to teach their children proper eating habits from the very beginning. Half of overweight school-age children and three quarters of overweight teens will become obese adults. So start promoting a healthy lifestyle now!

Teach your children the value of eating a healthy diet and maintaining an active lifestyle and you need not worry about the increasingly-evident link between obesity and cancer.