Should You Try Soy for Hot Flashes?


If you are one of the many women desperate to relieve your hot flash that plagues you in the bedroom and boardroom,  then you mostly likely have heard that Soy may help relieve your frequency of hot flashes.

To start, your episodes of hot flashes are due to low estrogen level.  Your estrogen level is low because you are menopausal due to surgery or natural aging.  There are other conditions that can cause low estrogen level but menopause is the most common one.

Regardless of the reason, hot flashes, night sweats. insomnia, vaginal dryness  and the many other symptoms associated with menopause is really affecting your livelihood. Many women take Hormone Replacement Therapy (HRT) prescribed by their physician, but like you many women are reluctant to take HRT due to the possible risk of breast cancer and cardiovascular events.

If you’ve taken an interest in health research over the last few decades, you already know that the verdict is still out on whether soy and soy products are helpful to prevent heart and blood vessel diseases and certain types of cancer such as breast and prostate cancer.

Furthermore, if you are vegan and most of your source of protein is from soy products such as tofu and edamame, you might still be confused about its safety.

In addition, as you opt in for healthier foods and try to introduce more plant based food in your diet, then you also might have switched from animal proteins and fats to plant based proteins and fats.

If you have breast cancer or at risk for it then the effects of soy is worth discussing with your healthcare provider.

What is Equol?

Soy is also a popular remedy to alleviate hot flashes during menopause and build up bone during menopause. Researchers first reported the reduction in menopausal hot flashes in 1992, based on epidemiological evidence. They noted that in countries where there was a high consumption of soy there was a low incidence of hot flashes.

Surprisingly,  the reason for the improvement in symptoms is not due to Soy but is due to Equol.  Equol is a byproduct of Soy Isoflavone Daidzein.

Equol is produced in your gut when soy is interacts with certain bacteria in your intestine. However, if you don’t have enough of the right bacteria that breakdowns Soy to Equol  then Soy may not be effective in helping you alleviate your hot flash symptoms.

Will your doctor recommend soy supplements as an alternative to HRT? Maybe not.

As with many things in health and science some doctors say yes to soy; others say no. They don’t always agree on what’s best.

But not surprisingly, the doctors that say no to soy may be basing their decisions on studies in the past.  These studies were divided on the results for women who are having hot flashes.

In fact, even WebMD has only reported on studies done up until 2010.

Well, it’s 2020 now, and those studies are already 10 years old. Let’s bring in the new clinical evidence, doctors!

What Current Soy Studies Show?


An Austrian study published in 2018 that was set up in one of the best ways to perform a medical study – double-blind and placebo-controlled – reports good outcomes for women with at least seven hot flashes daily. Having that many hot flashes daily was one of the criteria for the menopausal women.

The  Austrian study done through a department of gynecology and obstetrics, 192 women with at least 7 hot flashes daily took 100 mg isoflavone glycosides daily or with placebo for 12 weeks. The isoflavone is the active ingredient in soy, the one that can mimic hormonal responses in the body because its structure is similar to the structure of 17-B-estradiol.

Hot flashes were reduced by 43.3% when the women took soy. That means if they were having 7 hot flashes daily, they reduced them down to 3. And when you think about it, that means the women could much better control their daily life activities.

The researchers then went to open treatment with soy after the first 12 weeks, where anyone in either group could take the soy daily. The success rate then rose to 68% reduction in hot flashes in both groups of women. Instead of 7 hot flashes daily, they were down to 2 daily.

When the smart researchers analyzed the data comparatively, they found that the best effects were in those who were classified as severe for menopausal symptoms at the beginning of the study. They had a 78% improvement in hot flash symptoms compared to only 24% improvement in the placebo group.

Surprisingly, the researchers concluded that soy extract with 100 mg isoflavone glycosides modestly but significantly reduced menopausal hot flashes.

This isn’t the only more recent study. A Chinese study evaluating medical literature over the last two decades (not stopping at 2010) published in 2018 concluded that dietary or supplemental isoflavones have protective effects on the health of humans and animals and may be effective and safe.

And in Korea, researchers searched Korean and Chinese language scientific and medical databases, not just those written in English. They found a significant benefit of soy to lower hot flash scores in the number of hot flashes experienced daily and how severe each hot flash was.

Safety of Soy?


Some alternative health doctors question the safety of using soy, stating that it is often genetically engineered, and GMO foods seem to lead to destruction of the immune system after about 20 years. However, there haven’t been any studies on this topic yet.

In 2016, scientists and doctors from European countries such as Italy, Slovenia, Austria, and Switzerland concluded that soy was safe via an in-depth risk assessment: “The amply available human data does not indicate any suspected harmful effects from a potential interaction of isoflavones with hormone-sensitive tissues in the mammary gland, the uterus and the thyroid gland. Safety was ascertained with long-term intake of up to 150 mg isoflavones per day ingested for the duration of at least 3 years.”

The scientists then even negated the idea that soy should be eliminated from the diet of those taking certain estrogen blocking drugs after breast cancer: “Moreover, high isoflavone intake was found to have preventative effects with respect to breast cancer. Clinical findings indicate potential benefits of isoflavone exposure even during breast cancer treatment with tamoxifen or anastrozole.”

Is Soy the Only Natural Remedy to Help Reduce Hot Flashes?


Women have been using herbal medicines since the beginning of time to help control their hot flashes. They have used them long before hormone therapy came onto the scene from the medical profession – and without side effects.

Iranian medical researchers reported in 2016 in one of their medical journals that herbal medicine can be seen as an alternative treatment for women experiencing hot flashes and concluded that the research they found showed the remedies worked. They also stated that health providers in Iran embraced using the remedies.

Some of the remedies they stated that were effective included Anise, licorice, soy, black cohosh, red clover, evening primrose, flaxseed, Salvia officinalis, Passiflora itex, Agnus castus, avocado with soybean oil, St. John’s Wort and valerian.

That’s a lot to choose from. Therefore, if you are reluctant to try hormone replacement therapy then you can explore one of these other options.


Imhof, M., Gocan, A., Imhof, M., and Schmidt, M. Soy germ extract alleviates menopausal hot flushes: controlled double-blind trial. Eur J Clin Nutr 2018 Jul;72(7):961-970.

Ghazanfarpour, M., et al. The efficacy of Iranian herbal medicines in alleviating hot flashes: a systematic review. Int J Reprod Biomed (Yazd).2016 Mar; 14(3):155-66.

Xiao, Y., et al. Comprehensive evaluation of the role of soy and isoflavone supplementation in humans and animals over the last two decades. Phytother Res 2018 Mar;32(3):384-394.

Daily, J.W., et al. Equol decreases hot flashes in postmenopausal women: a systematic review and meta-analysis of randomized clinical trials. J Med Food 2019 Feb;22(2):127-139.

Schmidt, M., et al. Consensus: soy isoflavones as a first-line approach to the treatment of menopausal vasomotor complaints. Gynecol Endocrinol 2016 Jun;32(6):427-30.


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