Prostate cancer prevention by nutritional means to alleviate metabolic syndrome.
In 1987 when Reaven introduced syndrome X (metabolic syndrome, or MS), we were studying skeletal muscle insulin resistance and found that when rodents were fed a high-fat, refined-sugar (HFS) diet, insulin resistance developed along with aspects of MS, including hyperinsulinemia, hypertension, hypertriglyceridemia, and obesity. MS was controlled in rodents by switching them to a low-fat, starch diet and was controlled in humans with a low-fat starch diet and daily exercise (Pritikin Program). Others reported inverse relations between serum insulin and sex hormone-binding globulin (SHBG). When subjects were placed on the Pritikin Program, insulin fell and SHBG rose and it was suggested that prostate cancer might also be an aspect of MS. A bioassay was developed with tumor cell lines grown in culture and stimulated with serum before and after a diet and exercise intervention. Diet and exercise altered serum factors that slowed the growth rate and induced apoptosis in androgen-dependent prostate cancer cells. Changes in serum with diet and exercise that might be important include reductions in insulin, estradiol, insulin-like growth factor-I (IGF-I), and free testosterone with increases in SHBG and IGF binding protein-1. Hyperinsulinemia stimulates liver production of IGF-I, plays a role in the promotion of prostate cancer, and thus is the cornerstone for both MS and prostate cancer. Adopting a low-fat starch diet with daily exercise controls MS and should reduce the risk of prostate cancer.
Barnard
R James
RJ
Department of Physiological Science, University of California, Los Angeles, CA 90096-1606, USA. jbarnard@physci.ucla.edu
D018752:Diet, Fat-Restricted; D004038:Diet, Reducing; D015444:Exercise / Q000502:physiology*; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000378:metabolism / Q000502:physiology; D007334:Insulin-Like Growth Factor I / Q000378:metabolism / Q000502:physiology; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000150:complications / Q000178:diet therapy*; D009747:Nutritional Physiological Phenomena / Q000502:physiology*; D011471:Prostatic Neoplasms / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D012307:Risk Factors; D014407:Tumor Cells, Cultured
D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I