How is cancer linked to obesity?

Obesity increases cancer risk. The exact reasoning remains unclear, but fat cells are highly active, releasing large amounts of hormones like estrogen, insulin, and insulin-like growth factors that can fuel many cancers.

The risk for many types of cancers declines when you lose weight, but it's particularly true for breast and uterine cancer, where losing only 8 pounds can significantly reduce the levels of specific carcinogenic hormones.

Obesity increases the risk of developing cancers of the colon, pancreas, endometrium, and breast cancer in postmenopausal women. We used to think adipose tissue or body fat was inactive, and acted as a "shock absorber" for our organs, as well as acting like an insulator to keep us warm. We are learning that fat acts like an organ pumping out estrogen and other hormones like insulin like growth factor into the bloodstream. These hormones promote the growth of abnormal cells and inhibit cells from dying when they should. Losing a small amount of weight by reducing calorie intake and increasing physical activity can help lower the amounts of these hormones in the blood.