Obesity causes CANCER – scientists have discovered an ironclad connection between excess weight and tumors. Fat increases the risk of 18 TYPES of cancer: leukemia, thyroid, kidney, brain and central nervous system, uterus, breast, gallbladder, bile duct, colorectal, liver, head, neck, bladder, multiple myeloma, non-Hodgkin's lymphoma, esophageal adenocarcinoma and stomach cancer. Fat cells secrete special enzymes that damage DNA