title: Dietary fat and neoplasia--the role of net energy in enhancement of carcinogenesis: effects of fat and calories on the immune system.
abstract: The mechanism by which carcinogenesis is enhanced by dietary fat is not understood. We know that a minimum level of essential fatty acids (EFA) is necessary for mammary tumor development and that this level probably exceeds the normal requirements of rats. Once the minimum level of EFA has been supplied, the calorie contribution of dietary fat may account for its enhancement of carcinogenesis. In this regard, we must recognize that the efficiency with which dietary energy is utilized is known to increase as the fat content of the diet is raised. Hence even when fed isocalorically to low fat diets, high fat diets will provide more net energy. Modulation of host immunity has been proposed as a mechanism of action of both fat and calorie intake on neoplasia. We review the literature examining the effects of fat and calories on the cell-mediated immune system, that arm of the immune system most directly responsible for the killing of neoplastic cells.
mesh_terms: D004041:Dietary Fats; D004734:Energy Metabolism; D006801:Humans; D007111:Immunity, Cellular; D009369:Neoplasms / Q000209:etiology* / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D004041:Dietary Fats