A new study, published in the journal Menopause, found a plant-based diet rich in soy reduces moderate-to-severe hot flashes by 84%, from nearly five per day to fewer than one per day. During the 12-week study, nearly 60% of women became totally free of moderate-to-severe hot flashes. Overall they (including mild ones) decreased by 79%. The study shows that diet changes can be much more powerful for treating these issues than scientists had thought.
The study used no hormone medications or extracts. Instead, the research team tested a combination of a low-fat plant-based diet plus 1/2 cup of ordinary soybeans added to a salad or soup each day. Researchers believe this is a game changer for women aged 45 and over, most of whom we now know can get prompt relief from the most severe and troubling menopause symptoms without drugs.
As many as 80% of postmenopausal women suffer from hot flashes. Heat wells up from the chest, causing flushing, sweating, and chills. At night, hot flashes interfere with sleep. Estrogen-based medications were once routinely used to treat them but have been shown to increase the risk of breast cancer and other serious problems. Isoflavone extracts from soybeans work only modestly, leaving women and their doctors with few effective options.
The participants in the study were postmenopausal women reporting two or more hot flashes per day. They were assigned to a diet consisting of a low-fat, vegan diet, including half a cup of cooked soybeans daily for 12 weeks. Frequency and severity of the issues were recorded using a mobile application, and vasomotor, psychosocial, physical, and sexual symptoms were assessed using the Menopause Specific Quality of Life Questionnaire (MENQOL).
Each participant was given a digital self-calibrating scale to track body weight day by day, a mobile app to track hot flashes in real time, and an Instant Pot to prepare soybeans at home. Each week, the group got together with the research team via Zoom.
Since previous studies have shown that soy could be beneficial, the diet change was included in the test. Researchers believed that the combination is what was important. By the end of the study, the majority of women on a plant-based diet rich in soy reported that they no longer experienced moderate-to-extreme hot flashes at all and that they experienced significant improvements in their quality of life.
Total hot flashes decreased by 79% and moderate-to-severe hot flashes decreased by 84% in the intervention group. At the study’s conclusion, 59% of intervention-group participants reported becoming free of moderate and severe hot flashes.
In previous randomized trials, soy products have been shown to modestly reduce the frequency of hot flashes. The researchers theorize that the effect may be a result of soy products containing isoflavones, which can be metabolized by gut bacteria into equol–a nonsteroidal compound that has been shown in some studies to reduce the incidence and severity of hot flashes. Previous studies have also shown that those following vegetarian or vegan diets produce higher levels of equol. The new study showed a more robust response, using the combination of a plant-based diet plus soy.
Many study participants also reported improvements in sexual symptoms, mood, and overall energy.
The study was based on the new approach to menopausal symptoms described by Dr. Barnard in his book Your Body in Balance.