Excess body fatness and cancer risk: a summary of the epidemiologic evidence

Excess body fatness has been associated with various health outcomes including premature mortality, cardiovascular disease, type 2 diabetes, and various types of cancer. Recent expert panels have reviewed the scientific evidence relating excess body fatness with risk of specific cancer types. This evidence includes intervention trials, cohort and case-control studies, experimental animal studies, and mechanistic studies. To date, these consensus panels have concluded that 13 cancers have sufficient evidence and biologic plausibility linking excess body fatness as a cause of cancer of the esophagus (adenocarcinoma), gastric cardia, colon and rectum, liver, gallbladder, pancreas, meningioma, postmenopausal breast, endometrium, ovary, kidney, thyroid, and multiple myeloma. This article reviews the findings of these consensus reports along with additional considerations in better understanding the relationship between excess body fatness and cancer risk. Given that cancers linked to excess body fatness account for approximately 40% of all cancers, and approximately 70% of U.S. adults have overweight or obesity, it is critical to promote the maintenance of a healthy body weight throughout life for cancer prevention.