Dear Folks:
     Isn't it interesting that women should be cautious about soy-based 
menopause remedies, but that it is okay (according to that recent study in 
JAMA) for babies to be fed soy formula?

Caution Urged on Soy-Based Menopause Remedies

LONDON (Reuters Health) Apr 08 - So little is known about how plant 
oestrogens act on the human body that sales of soy supplements as a "natural" 
alternative to hormone replacement therapy (HRT) must be questioned, a 
researcher reported on Tuesday at British Endocrine Societies' annual meeting 
in Harrogate, Yorkshire. Soy has been widely promoted as a natural 
alternative to HRT. Soy contains genistein, a plant oestrogen that has 
similar but weaker effects as the oestrogen found in women. But Dr. Saffron 
Whitehead, reader in reproductive physiology at St. George's Hospital Medical 
School, London, said new studies on human cells have shown that genistein and 
other phyto-oestrogens may also block the enzymes that make these hormones. 
This could explain why the incidence of breast cancer, which in many cases is 
dependent on oestrogen, is about two thirds lower amongst Japanese and 
Chinese women who consume diets rich in soy compared with women living in 
England, she told her colleagues. Dr. Whitehead's team examined the effects 
of phyto-oestrogens on human ovarian cells obtained during procedures for in 
vitro fertilization. The results showed that several phyto-oestrogens, 
including genistein, inhibited the conversion of androgen to oestrogen. The 
researchers believe this could be significant in postmenopausal women because 
as ovaries cease to function in menopause, oestrogen converted from androgen 
becomes the only source of oestrogen. "This finding is potentially important 
to the phyto-oestrogen story," Dr. Whitehead said in a statement. "We really 
don't know how phyto-oestrogens act in the human body. They could be weak 
oestrogen mimics, oestrogen blockers or enzyme inhibitors. "If they do stop 
the natural production of oestrogens, we should consider whether soy 
supplements be sold as a natural alternative to HRT." 
        

Reuters Health Information 2002. © 2002 Reuters Ltd

Warmly, 
Nikki Lee



 

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