An estrogen-like substance found in soybeans is not effective in stopping or decreasing hot flashes ? the episodes of flushing, sweating and sensation of heat sometimes suffered by menopausal women ? disputing advertised claims for such products. Despite optimistic hopes that this soy phytoestrogen product would alleviate hot flashes, the scientific data from this study demonstrated that it did not help.

The study done at the Mayo Clinic found that 177 breast cancer survivors who took soy pills did not experience any noticeable changes. Despite optimistic hopes that this soy phytoestrogen product would alleviate hot flashes, the scientific data from this study demonstrated that it did not help.

Soy contains phytoestrogens, which are weak estrogen-like substances in the soybean, that some believed would bind to estrogens to alleviate hot flashes. The study was prompted by numerous advertisements that included claims about the benefits of soy for ending or lessening hot flashes. The flashes, which also affect women undergoing chemotherapy or tamoxifen treatment for breast cancer, can be accompanied by palpitations and feelings of anxiety, and can be very disruptive to life.

One-half of the study?s participants spent four weeks taking soy pills that contained 50 milligrams of soy isoflavones three times a day, while the other half took took inert placebos. Each group switched regimens after four weeks, and completed another four weeks under the new regimen while keeping detailed diaries of their reactions.

Journal of Clinical Oncology March 1, 2000

Dr. Mercola's Comment:

Many women correctly reject hormone replacement therapy as treatment for hot flashes due to concerns that estrogen might promote breast cancer. Women being treated for breast cancer often are prescribed tamoxifen, which has been shown to decrease the risk of breast cancer recurrence, but may increase hot flashes.

The study documenting soy's lack of usefulness continue to mount and the truth will eventually surface. Soy is not the health food that we are lead to believe by the multi billion dollar edible oil industry research.

However, prior to this study I had some patients tell me that they did find some relief with the soy for the hot flashes, so I wonder if the product or dose was correct in this study. There is one potential application of soy that is not widely known.

If one believes D'damo's blood type work, he is a fond advocate of using small amounts of soy (one half tsp a few times a day of tofu) as a specific lectin supplement to bind breast cancer cells. I suspect there may be some validity to his recommendations and I have been advising patients of this who have breast cancer.

The total amount of soy is quite small - its antinutrient properties maybe more than compensated for by the beneficial effect. However, it is likely that tempeh would provide the same result but it is far less palatable to most.

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