Unveiling the actual impact of soy consumption on hot flashes
The evidence supporting the benefits of whole soy foods, particularly fermented types like tempeh, miso, and natto, in reducing hot flashes in menopausal women, has been gaining attention. This is largely due to the presence of phytoestrogens, particularly isoflavones such as daidzein and genistein, in these foods.
According to a study published by the North American Menopause Society, soy isoflavones can help alleviate vasomotor symptoms like hot flashes and night sweats. The study, led by Dr. Neal Barnard, president of the Physicians Committee for Responsible Medicine, suggests that changes in diet, specifically a plant-based diet including soy, can be more potent for relieving hot flashes than previously thought.
Clinical trials indicate that soy isoflavones, notably daidzein and genistein, reduce the frequency and severity of hot flashes, especially in women whose gut microbiota metabolize daidzein into the more active compound equol. A 2023 study published in Complementary Therapies in Medicine documented that a low-fat vegan diet including soy can reduce menopausal hot flashes by up to 95%.
Fermented soy foods, such as tempeh, miso, and natto, are whole soy products rich in isoflavones. These foods may deliver these compounds in a more bioavailable form because fermentation enhances isoflavone absorption and alters gut microbiota favorably. Though direct studies specific to fermented soy and hot flashes are fewer, their isoflavone content and improved bioavailability provide a mechanistic rationale.
The isoflavones act as selective estrogen receptor modulators (SERMs), with preferential binding to estrogen receptor beta (ERβ), allowing them to offer estrogenic benefits without the risks associated with menopausal hormone replacement therapy (HRT). Additionally, soy isoflavones have antioxidant and anti-inflammatory effects, which may indirectly support symptom reduction.
Dietitians recommend soy foods as part of a balanced diet to manage hot flashes, highlighting their natural estrogen-like activity. Whole-food soy forms like tempeh, miso, and natto contain multiple beneficial nutrients beyond isolated isoflavones, which may synergistically support menopausal symptom relief.
In the study, postmenopausal women reporting two or more hot flashes per day were assigned to a group that received a low-fat, vegan diet including half a cup of cooked soybeans daily. By the end of the study, the majority of women on a plant-based diet rich in soy reported no more moderate-to-extreme hot flashes. Participants in the intervention group also used a mobile application to track their hot flashes and reported improvements in sexual symptoms, mood, and overall energy.
Including whole soybeans in a plant-based diet, such as cooking them and adding them to soups or salads, can be beneficial. Natto, a food made from fermented soybeans, can help improve circulation and balance blood sugar. Natto can be found in many Asian specialty food stores or ordered online.
It's important to note that the study did not use any hormone medications or extracts. Soy, when consumed in a plant-based diet, can significantly reduce the number of hot flashes experienced by menopausal women.
- Whole soy foods, such as tempeh, miso, and natto, are often recommended by dietitians as part of a healthy diet and wellness routine, especially for menopausal women, as they may help alleviate hot flashes due to their rich content of isoflavones.
- A 2023 study published in Complementary Therapies in Medicine found that a low-fat vegan diet including soy can reduce menopausal hot flashes by up to 95%, suggesting that changes in diet, specifically a plant-based diet including soy, can be more effective in relieving hot flashes than previously thought.
- Fitness and exercise, in conjunction with a healthy diet rich in soy isoflavones, can further support overall health and well-being during menopause, as the antioxidant and anti-inflammatory effects of soy isoflavones may indirectly aid in symptom reduction.
