If you’re struggling with hot flashes, you may have heard that soy was helpful in turning down the heat. I’ve been writing about this for nearly 20 years and if you want to know exactly how soy works and easy to understand explanations of why soy is worth trying, especially if you are not able to take estrogen, my research can be found in my book, The Soy Solution for Menopause.
Study of plant-based foods including soy
Now a new study by Dr. Neal Barnard and colleagues in the October 2021 issue of the journal Menopause has added even more proof that the mighty soybean is helpful in cooling hot flashes.
Women who had at least two hot flashes a day were randomly assigned to receive either a low-fat, vegan diet that included 1/2 cup (86g) of cooked soybeans daily, or to just keep on eating what they had been before entering into the study, which lasted for 12 weeks. The investigators then measured the frequency and severity of the women’s hot flashes. The women were also asked questions about their psychosocial, physical and sexual symptoms over the time of the study.
The researchers from George Washington University School of Medicine and The University of Utah School of Medicine found that compared to the women who didn’t change their diets, the women who received the low-fat, vegan diet that included 1/2 cup (86g) of cooked soybeans daily had a 79% reduction in their moderate-to-severe hot flashes. The women who didn’t change their diets had no improvement in their symptoms.
The researchers concluded that changing the diet to a low-fat vegan diet that includes 1/2 cup daily of cooked soybeans can improve their quality of life and reduce hot flashes.
While the results are very impressive, soy shouldn’t be seen as a silver bullet for everyone. However, in other parts of the world where the people eat less meat and eat more vegetables, hot flashes are generally lower. And in Asia, soybeans are an important part of the daily diet. In addition, Americans eat much more meat and consume much more dairy than people who live in countries like Japan. Meat and dairy can increase the amount of inflammation in the body and even change the types of bacteria in the gut – known as the microbiome. Those changes in the microbiome may play a role in the severity of hot flashes.
The gut microbiome can digest the soy (mostly the ingredient daidzein) and create a byproduct called equol that studies show is effective in lowering hot flashes. In Asia, about 50-60% of people are able to produce equol; in the US only about 20-30% can. There is more and more research in this area now.
What you can take home from this report is very clear: If you are suffering from moderate to severe hot flashes and cannot or will not take estrogen, cutting down on or cutting out meat and dairy and increasing a more plant-based diet that ideally includes soy is very likely to make you feel better and lower your hot flashes. As Hippocrates said thousands of years ago, “Let food be thy medicine and medicine be thy food.”