How significant are environmental estrogens to women?
Women are exposed to xenobiotic estrogens at least to the same extent as men. These estrogenic chemicals are either from plant material in the diet (phytoestrogens) or from industrial sources. Mainly industrially derived environmental estrogens may accumulate within the food chain and persist in human adipose tissue. In contrast, phytoestrogens do not bioaccumulate and are rapidly excreted in urine. The phytoestrogens probably represent the source of most extensive exposure for humans. Epidemiological evidence suggests that diets rich in phytoestrogens are associated with reduced incidences of cardiovascular disease, breast cancer, prostate cancer and osteoporosis. The numerous bioactivities (other than just estrogenicity) of phytoestrogens and related dietary compounds make it difficult to single out the mechanisms mediating such protective effects. The possibility that the newly discovered estrogen receptor beta may be an important modulator of phytoestrogen action is opening up new lines of research. While the evidence suggests that phytoestrogens may be of positive relevance to postmenopausal women, indications that exposure of women to industrially derived xenobiotic estrogens provides risks to health remain unproven. Further work is necessary to clarify the relative importance of 'xenobiotic' estrogens to human health, but it must be emphasized that the estrogenic potency of all the xenobiotic estrogens is very low compared with that of endogenous estrogens.
Cassidy
A
A
Centre for Nutrition and Food Safety, School of Biological Sciences, University of Surrey, London, UK.
Milligan
S
S
D001943:Breast Neoplasms / Q000209:etiology; D002318:Cardiovascular Diseases / Q000517:prevention & control; D004032:Diet; D004781:Environmental Exposure; D004785:Environmental Pollutants; D004968:Estrogens, Non-Steroidal / Q000009:adverse effects / Q000378:metabolism* / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007529:Isoflavones; D015663:Osteoporosis, Postmenopausal / Q000517:prevention & control; D048789:Phytoestrogens; D028321:Plant Preparations; D011960:Receptors, Estrogen / Q000187:drug effects / Q000502:physiology; D012307:Risk Factors
D004785:Environmental Pollutants; D004968:Estrogens, Non-Steroidal; D007529:Isoflavones; D048789:Phytoestrogens; D028321:Plant Preparations; D011960:Receptors, Estrogen