Premenopause

In a 1996 review, the Committee of Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) estimated the intake of isoflavones from soya-milk to be approximately 4 mg/kg/day over the first 4 months of life. This is greater than that associated with hormonal effects in premenopausal women, but the COT nonetheless supported the existing Department of Health s advice that... 

As a rule of thumb, a person s risk drops about 25% for each increase of 5 mg/dL in HDL concentration. Normal values are about 45 mg/dL for men and 55 mg/dL for women, perhaps explaining why premenopausal women appear to be somewhat less susceptible than men to heart disease. 

Aromatase activity, and hence the capacity to synthesize estrogens, is found in a variety of tissues in the body. Gonadal sites include the ovaries in premenopausal women and the testes in men. Important extragonadal sites of aromatase activity include the placenta, chondrocytes and osteoblasts of bone, adipose tissue, muscle and brain. Aromatase plays an important... 

In premenopausal women the ovary is the richest source of aromatase and hence estrogen. Aromatase is confined to the granulosa cells and is produced under the influence of gonadotropins (FSH and LH). Despite being a rich source of aromatase, three separate studies have shown that aromatase inhibitors are unable to sufficiently suppress ovarian estrogen production to postmenopausal levels. One explanation for this phenomenon may be a compensatory rise in gonadotrophins which maintains adequate estrogen production, despite the presence of the inhibitor. As such aromatase inhibitors cannot be used in premenopausal breast cancer patients. After menopause, ovarian... 

Aromatase inhibitors have also been used in premenopausal women for the treatment of endometriosis and to induce ovarian folliculogenesis as part of the treatment for infertility. 

ERT is a clinical treatment whereby premenopausal estrogen levels are restored and the symptoms of menopause are relieved. 

Studies with fenretinide in woman with stage I breast cancer did not show an overall effect of decreasing the risk of contralateral breast cancer. A protective effect could only be observed in premenopausal women, probably due to the modulation of the insulin-like growth factor 1 (IGF-1) by fenretinide in this population. 

DUNCAN A M, MERZ B E, XU X, NAGEL T C, PHIPPS W R, KURZER M S (1999a) Soy isoflaVOneS exert modest hormonal effects in premenopausal women. J Clin Endocrinol Metab. 84 192-7. 

NAGATA c, KABUTO M, KURISU Y, SHIMIZU H (1997) Decreased serum estradiol concentration associated with high dietary intake of soy products in premenopausal women. Nutr Cancer. 29 228-33. 

Tsuchida et al., 1999 Japanese premenopause n = 995 Dietary intake of soybeans(at least 2 servings/ wk) correlated with higher BMD (4.5%) of the second metacarpal bone... 

Mei et al., 2001 Chinese postmenopause n = 357 premenopause n = 293 Significant differences found in BMD of the lumbar spine and hip between highest and lowest tertile of isoflavone intake for postmenopausal but not for premenopausal women... 

Ho et al., 2001 Chinese premenopause n= 132 Estimated isoflavone intake range 7.4-48.3 mg/d. Higher BMD of liunbar spine in the 4 quartile... 

Anderson et al., 2002 mixed ethnic premenopause placebo, n = 13 supplement, n = 15 Controlled, double-blind intervention in young, adult females testing the effect of supplementation with soy protein providing 90 mg isoflavones/day compared to soy protein without isoflavones. No changes in BMD or BMC were observed in either group after 12 months. 

CASSIDY A, BINGHAM s and SETCHELL K D R (1994) Biological effects of a diet of soy protein rich in isoflavones on the menstrual cycle of premenopausal women. Am J Clin Nutr 60, 333-40. 

DUNCAN M, MERZ-DEMLOW E, XU X, PHIPPS w R and KURZER M s (2000) Premenopausal equol excretors show plasma hormone profiles associated with lowered risk of breast cancer. Cancer Epidemiol Biomarkers Prev 9, 581-6. 

MEi J, YEUNG s s, RUNG A w (2001) High dietary phytoestrogen intake is associated with higher bone mineral density in postmenopausal but not premenopausal women, J Clin Endocrinol Metabol 86(11), 5217-21. 

For long-term exposure, questions have been raised on proliferative effects of breast duct epithelial cells in premenopausal women (Messina and Loprinzi, 2001, and refs therein). 

KURZER M s (2002) Elormonal effects of soy in premenopausal women and men. JNutr. 132 (3) 570S-573S. 

MERZ-DEMLOW B E, DUNCAN A M, WANGEN K E, XU X, CARR T P, PHIPPS W R and KURZER M S (2000) Soy isoflavones improve plasma lipids innormocholesterolemic, premenopausal women. Am J Clin Nutr. 71 (6) 1462-9. 

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