Obesity and Cancer Risk: Recent Review and Evidence
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The prevalence of overweight and obesity is increasing worldwide, and the evidence base for a link between obesity and cancer is growing. In the United States, approximately 85,000 new cancer cases per year are related to obesity. Recent research has found that as the body mass index increases by 5 kg/m2, cancer mortality increases by 10%. Additionally, studies of patients who have had bariatric surgery for weight loss report reductions in cancer incidence and mortality, particularly for women. The goal of this review is to provide an update of recent research, with a focus on epidemiologic studies on the link between obesity and cancer. In addition, we will briefly review hypothesized mechanisms underlying the relationship between obesity and cancer. High priorities for future research involve additional work on the underlying mechanisms, and trials to examine the effect of lifestyle behavior change and weight loss interventions on cancer and intermediate biomarkers.
KeywordsNeoplasm Obesity Overweight Cancer risk Intervention Review Insulin Insulin-like growth factors Sex steroid hormones Adipokines Hypoxia Oxidative stress
Maria Chang, a doctoral student, is supported in part by a cancer prevention fellowship that is supported by the National Cancer Institute grant R25E CA56452, Shine Chang, Principal Investigator.
No potential conflicts of interest relevant to this article were reported.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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