Estrogens, dietary

Since dietary cereals are low in sulfur-containing amino acids, they produce an alkaline urine which favors the retention of bone minerals. In post-menopausal women, there appears to be some interaction between the diet and the effect produced by estrogens on bone mineral content (28). 

Pelissero, C., Lemenn, E, and Kaushick, S. (1991). Estrogenic effect of dietary soya bean meal on vitellogenesis in cultured Siberian sturgeon Acipenser baeri. General and Comparative Endocrinology 83, 447 57. 

Setchell, K.D.R., Gossehn, S.J., and Welsh, M.B. et al. (1987). Dietary estrogens—a probable cause of infertility and liver-disease in captive cheetahs. Gastroenterology 93, 225-233. 

The enzyme aromatase catalyses the conversion of testosterone to estrogen. A number of in vitro studies have shown that phytoestrogens can inhibit aromatase (Adlercreutz et al, 1993 Kao et al, 1998 Pelissero et al, 1996). However, the high concentrations required to cause this effect in vitro are unlikely to be achieved in vivo following dietary exposure. 

BAIRD D D, UMBACH D M, LANDSDELL L, HUGHES C L, SETCHELL K D R, WEINBERG C R, HANEY A F, WILCOX A J, MCLACHLAN J A (1995) Dietary intervention study to assess estrogenicity of dietary soy amongst postmenopausal women. J Clin Endocinol Metab 80(50, 1685-90. 

YCUNG H J, DCERGE D R, KIMBERLY F A, ALLRED C D and HELFERICH W G (2002) Dietary genistein negates the inhibitory effect of tamoxifen on growth of estrogen-dependent human breast cancer (MCF-7) cells implanted in athymic mice. Cancer Res 62,2474-77. 

It has been shown that in postmenopausal women habitually high intakes of dietary isoflavones are associated with higher bone mineral density (BMD) values at both the spine and hip region (Mei et al, 2001). It is conceivable that an isoflavone-rich diet may help to reverse the state of secondary hyperparathyroidism associated with estrogen withdrawal and hence lower the rate of bone turnover in postmenopausal women, thus reducing the risk of osteoporosis (Valtuena et al, 2003). Phytoestrogens could be used as natural SERMs (Brzezinski and Debi, 1999) and some studies (Setchell, 2001 and refs therein) support such an idea since the molecular targets of... 

SANTELL R c, CHANG Y c, NAIR M G and HELFERICH w G (1997) Dietary genistein exerts estrogenic effects upon the uterus, mammary gland and the hypothalamic/pituitary axis in rats. . 1 Nutr. 127 (2) 263-9. 

WAGNER J D, CEFALU W T, ANTHONY M S, LITWAK K N, ZHANG L and CLARKSON T B (1997) Dietary soy protein and estrogen replacement therapy improve cardiovascular risk factors and decrease aortic cholesteryl ester content in ovariectomized cynomolgus monkeys. ... 

PCB diets were associated with reproductive impairment including anovulation, fetal resorption, delayed ovulation, increased gestation, and decreased litter size. Hepatic estrogen binding site concentrations decreased with increasing dietary PCB concentrations but not uterine estrogen receptor sites... 

Shipp, E.B., J.C. Restum, S.J. Bursian, R.J. Aulerich, and W.G. Helferich. 1998b. Multigenerational study of the effects of consumption of PCB-contaminated carp from Saginaw Bay, Lake Huron, on mink. 3. Estrogen receptor and progesterone receptor concentrations, and potential correlation with dietary PCB consumption. Jour. Toxicol. Environ. Health 54A 403-420. 

Age, calcium intake, hormonal status, exercise and vitamin status have all been implicated in the development of osteoporosis. Estrogen levels represent an important factor in skeletal calcium retention and homeostasis. In therapeutic trials in which post-menopausal women were given daily doses of estrogens, such therapy has been demonstrated to be partially effective in reducing the rate of bone resorption. However, this therapy has the concomitant hazard of endometrial cancer (10). Vitamin D and its hormones have been given considerable attention in the more recent studies. Without adequate dietary and tissue levels of such vitamins, calcium absorption and bone status will be impaired. 

There has been some concern that the recently observed decline in sperm quality may be related to exposure to environmental estrogens (Sharpe and Skakkebaek, 1993) and at the same time there has been speculation that these estrogenic compounds may exert inhibitory effects against prostate cancer (Kurzer, 2002). Theoretically, exposure to high levels of dietary estrogens could alter the hypothalamic-pituitary-gonadal axis in men, but dietary studies to date have not shown such an hormonal effects. 

Hargreaves, D.F., Potten, C.S., Harding, C., et al. (1999). Two-week dietary soy supplementation has an estrogenic effect on normal premenopausal breast, J. Clin. Endocrinol. Metab., 84, 4017 024. 

Ju, Y.H., Allred, C.D., Allred, K.F., Karko, K.L., Doerge, D.R. and Helferich, W.G. (2001). Physiological concentrations of dietary genistein dose-dependently stimulate growth of estrogen-dependent human breast cancer (MCF-7) tumors implanted in athymic nude mice, J. Nutr., 131, 2957-2962. 

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