British Medical Journal 1990 (Oct 20); 301 (6757): 905–906 ~ FULL TEXT
G Wilcox, M L Wahlqvist, H G Burger, and G Medley
Monash University Department of Medicine,
Prince Henry's Hospital,
Melbourne, Victoria, Australia.
From the FULL TEXT Article:
Crops grown as animal pasture are known to have oestrogenic activity,  and some foods contain potential oestrogenic analogues such as the isoflavonoids (isoflavones and coumestans), lignans, and resorcyclic acid lactones,  which may be activated or inactivated.  We studied the effect of three foods reported to induce vaginal oestrus in laboratory animals  in postmenopausal
women not taking oestrogen replacement therapy.
Subjects, methods, and results
We studied 25 postmenopausal women who were
non-smokers, in good general health, and taking no
drugs known to affect oestrogen state (mean age 59
(range 51–70); body mass index 24.4 (range 18.7–31.6)
kg/m2; years after menopause 8.1 (range 1–20)). The
protocol was a latin square design with a two week run
in period and a six week experimental period. The
women recorded their normal diet for 14 days and were
asked to repeat the fortnightly diet throughout the
study. During the experimental period the diet was
supplemented with soya flour (45 g daily), red clover
sprouts (10 g dry seed daily), and linseed (25 g
daily), each for two weeks in turn. To check compliance
the women returned residual food. Blood samples were
taken weekly and lateral wall vaginal smears taken
fortnightly and at follow up two and eight weeks after
supplementation finished. Analysis was on intention to
treat, but 23 women completed the study.
We examined the dependent variables vaginal cell
maturation and serum concentrations of luteinising
hormone and follicle stimulating hormone. The
cumulative effects of the three foods at six weeks were
compared with baseline by the paired t test, as were the
residual effects, two and eight weeks after the last food
supplement. We found significant differences in
vaginal cytology after six weeks' supplementation
(p<001, 95% confidence interval 6.0 to 17.6), which
persisted for two weeks after treatment (p<002), but
cytology returned to baseline after eight weeks (Table).
sources of oestrogenic activity. Conversely, tamoxifen,
an antioestrogen, can have oestrogenic effects on
vaginal cytology. 
Patterns of food intake may modulate the severity of
the menopause as it is an oestrogen deficiency state.
Up to half of the diet of some populations may
comprise foods containing phyto-oestrogens, whereas
in our study such foods comprised only about 10% of
energy intake for a fairly short time. Whether menopausal
symptoms differ in such populations would be
We thank our statistical adviser, Steve Farrish, from the
department of social and preventive medicine, Monash
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