A plant-based diet is about as effective as hormone replacement therapy for reducing menopausal hot flashes— and it doesn't come with the associated health risks, a new study has found.
The research, published Wednesday by the North American Menopause Society in the journal Menopause, found that a vegan diet rich in soy reduced moderate to severe hot flashes by 88% and helped women shed, on average, eight pounds in 12 weeks.
"It is precisely the diet that would be expected to reduce the health concerns of many women reaching menopause: an increasing risk of heart disease, breast cancer and memory problems.”
Neal Barnard, MD
The study analyzed 84 postmenopausal women reporting two or more hot flashes per day. They were randomly assigned for 12 weeks either to an intervention group – consisting of a low-fat, vegan diet, including half a cup of cooked soybeans daily – or to a control group that had no diet intervention.
“This study demonstrates the effectiveness of a dietary intervention for menopausal symptoms,” according to lead researcher Neal Barnard, MD. “As well, it is precisely the diet that would be expected to reduce the health concerns of many women reaching menopause: an increasing risk of heart disease, breast cancer and memory problems.
“We do not fully understand yet why this combination works but it seems that these three elements are key: avoiding animal products, reducing fat and adding a serving of soybeans,” Barnard said. "Our results mirror the diets of places in the world, like pre-Westernized Japan and modern-day Yucatán Peninsula, where a low-fat, plant-based diet including soybeans is more prevalent and where postmenopausal women experience fewer symptoms.”
Was symptomatic improvement attributed to cooler temperatures?
The new findings are the second phase of a two-part trial, the first of which was also published in Menopause in 2021.
The study notes that the 2021 trial was conducted in the fall, raising eyebrows that hot flash reduction could have been attributed to cooler weather instead of diet. But in the latter study, done as the weather warmed up in the spring, women saw the same benefits, ruling out the impact of outside temperature.