Interrelationships of high fat diets, obesity, hormones, and cancer.

Abstract

Obesity is defined as excess body fat and results from an imbalance of energy intake and expenditure (1). This simple definition and the application of thermodynamic principles of energy balance do not adequately express the fact that much remains unknown about this complex disorder (2). In common with other chronic diseases including cancer, it is rare for obesity to be the expression of a pure genetic or medical disorder. In the majority of cases, obesity results from a combination of physiological, psychological and environmental factors (3). A genetic predisposition to obesity mediated by a large number of genes is likely to interact with a permissive high fat diet in the presence of reduced physical activity to result in obesity(4). Obesity is the most prevalent disorder in the United States affecting up to one-third of the population. The endocrine system which is critically involved in many common forms of cancer has also been shown to translate environmental influences into excess adiposity (5). Many hormones involved in obesity also play a role in the initiation and promotion of cancer both at a cellular, paracrine, and systemic level (6). For example, reproductive hormones are critically involved in both obesity and cancer. In patients with primary anorexia nervosa and malnutrition, reproductive hormone secretion is reduced and can result in infertility. Conversely, with obesity excess secretion of reproductive hormones (e.g. estrogens) has been observed and implicated in the etiology of breast cancer (7). This chapter will examine the potential role of hormones in the etiology of obesity in the hopes of stimulating additional research on the role of obesity in modulating the risk of developing several common forms of cancer.KeywordsBreast CancerGrowth HormonePremenopausal WomanReproductive HormoneHigh Fiber DietThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.