BMI, Obesity and Cancer Risk
Increasing Body Mass Index (BMI) is a growing problem from several perspectives. Although it is well known that tobacco smoking greatly increases cancer risk, today, a higher proportion of the global population is affected by increased BMI, and a developing body of evidence now supports the role played by BMI in the risk of a large number of different cancers. Unravelling this connection is a key priority. In this dedicated Collection, our epidemiology subject editor, Per Hall (Karolinska Institute, Sweden), has selected some of our recent articles that aim to understand this link. Obesity is associated with disorders that influence cancer occurrence, such as the global epidemic of diabetes. Furthermore, BMI change over life has recently been identified as a risk factor for cancer. Avoiding excess body weight in middle adulthood, irrespective of BMI category at baseline, reduces the risk of several obesity-related cancers. Lastly, several recent studies have addressed the influence of obesity on cancer prognosis; results are conflicting, and more information is warranted before firm conclusions can be drawn.