There’s been only preliminary research on the link between diet and hot flushes, but some nutrients show promise for this uncomfortable and surprisingly mysterious phenomenon that affects some 75% to 80% of menopausal women around the world.
“We don’t have exact answers, just several theories and questions,” said Dr Arianna Sholes-Douglas, a US obstetrician-gynaecologist and author of The Menopause Myth: What Your Mother, Doctor and Friends Haven’t Shared About Life After 35.
With the decline in oestrogen during the menopause transition, the body’s internal thermostat sometimes registers the body as hotter than it is, which sets off the rapid sweating and a dilation of blood vessels in an attempt to cool down.
But what triggers that process and why?
It’s unclear. How are hot flushes connected with other health issues, like cognitive concerns and cardiovascular disease? Also hazy. Treatment options are limited to hormones and just one non-hormonal drug approved by the US Food and Drug Administration.
All of which, Sholes-Douglas added, is a clear reflection of the scant attention and little funding devoted to medical research into this phase of a woman’s life.
However, reports The New York Times, in the past two decades, researchers have started to investigate another potential source of relief: diet.
The idea stems from studies that have found that hot flushes differ across cultures and might be a largely Western experience. With that in mind, researchers have hypothesised that environmental factors, like diet, might play a part in this difference.
But many of the studies on dietary interventions are small or inconclusive, said Dr Stephanie Faubion, medical director for the North American Menopause Society and a director of the Mayo Clinic Centre for Women’s Health. In studies that have suggested certain foods reduce hot flushes, the mechanisms at work are not fully understood, she added.
Still, there is no harm in adjusting your diet to see if it might help manage your hot flushes, Faubion said.
What are perimenopause and menopause?
Perimenopause is the final years of a woman’s reproductive years that leads up to menopause, the end of a woman’s menstrual cycle. Menopause begins one year after a woman’s final menstrual period.
The symptoms of menopause can begin during perimenopause and continue for years. Among the most common are hot flushes, depression, genital and urinary symptoms, brain fog, and skin and hair issues.
Usually, a low-dose birth control pill can control bleeding issues and ease night sweats during perimenopause. Avoiding alcohol and caffeine can also help, while cognitive behavioural therapy and even meditation can make them more tolerable. Menopausal hormone therapy and the selective serotonin reuptake inhibitor paroxetine can also ease some symptoms.
Perimenopause usually begins in a woman’s 40s and can last for four to eight years. The average age of menopause is 51, but for some it starts a few years before or later. The symptoms can last for a decade or more, and at least one symptom – vaginal dryness – may never get better.
Foods that might help
Soy products, like tofu and soybeans, contain isoflavones, chemicals that can bind to oestrogen receptors in the body, said Neal Barnard, an adjunct professor of medicine at the George Washington School of Medicine.
For that reason, the thinking goes, soy may mimic oestrogen. It’s one of the most-studied foods in connection to menopausal symptoms, and there’s some evidence that eating it might be associated with fewer hot flushes. But it’s unclear whether that’s because of the soy itself or another mechanism.
In a pair of studies, Barnard and his team randomly assigned 84 postmenopausal women who reported moderate to severe hot flushes to either their regular diets or a low-fat vegan diet rich in whole grains, fruits and vegetables, including a daily half-cup of cooked soybeans. Moderate to severe hot flushes decreased by roughly 80% in both studies.
“The caveat there is that this was essentially two different interventions – they were on a whole-food, plant-based diet and they had high soy,” said Faubion. “So what part of that was responsible for those results? We have no idea.”
The women in the study also ended up losing weight, which Faubion said is noteworthy because some studies have shown a correlation between increased body fat and hot flushes, particularly during certain stages of menopause.
Also of interest to researchers are omega-3 fatty acids. But while some studies have found that taking omega-3 supplements seems to reduce the frequency of the flushes, others found that they make no difference.
Supplements aside, the Mediterranean diet, which is rich in foods containing omega-3s – like flaxseeds, walnuts and fatty fish like salmon – has been shown in some studies to be associated with fewer hot flushes and other menopause symptoms.
Are there foods to avoid?
There’s some evidence that a diet high in sugar and fat is associated with worse hot flushes. Beyond that, doctors often suggest avoiding certain trigger foods and drinks, said Dr Hoosna Haque, an OB-GYN at Columbia University Irving Medical Centre, such as “spicy food, caffeine, alcohol and also really high-concentrated sugary foods and highly processed foods”.
But, she said, that recommendation is often based just on anecdotal evidence, and it’s not fully understood why those foods and drinks might trigger a hot flush.
“It might just be because they can cause spikes and drops in energy levels. Or because something like caffeine can dilate blood vessels — much like hot flushes do — and may set off a similar chain of events.”
Study 1 details
The Women's Study for the Alleviation of Vasomotor Symptoms (WAVS): a randomised, controlled trial of a plant-based diet and whole soybeans for postmenopausal women
Barnard, Neal; Kahleova, Hana; Holtz, Danielle; del Aguila, Fabiola; Neola, Maggie; Crosby, Lelia; Holubkov, Richard.
Published in Menopause in October 2021
Abstract
Objective
This study aimed to assess the effects of the combination of a low-fat plant-based diet and soybeans on the frequency and severity of menopausal hot flashes.
Methods
Postmenopausal women (n = 38) reporting two or more hot flashes/day were randomly assigned to a low-fat, vegan diet, including ½ cup (86 g) of cooked soybeans daily, or to no diet changes for 12 weeks. Frequency and severity of hot flashes were recorded using a mobile application, and vasomotor, psychosocial, physical, and sexual symptoms were assessed using the Menopause-Specific Quality of Life Questionnaire. Significance was assessed using t-tests (continuous outcomes) and chi-squared/McNemar tests (binary outcomes).
Results
Total hot flashes decreased 79% in the intervention group (P < 0.001) and 49% in the control group (P = 0.002; between-group P = 0.01). Moderate-to-severe hot flashes decreased 84% in the intervention group (P < 0.001) and 42% in the control group P = 0.009; between-group P = 0.01). From 0 to 12 weeks, 59% (10/17) of intervention-group participants reported becoming free of moderate and severe hot flashes (P = 0.002). There was no change in this variable in the control group (between-group P < 0.001). The Menopause-Specific Quality of Life Questionnaire revealed significantly greater reductions in the intervention group in vasomotor (P < 0.0001), psychosocial (P = 0.04), physical (P < 0.002), and sexual (P = 0.01) domains.
Conclusions
The combination of a low-fat, vegan diet and whole soybeans was associated with reduced frequency and severity of hot flashes and improved quality of life in vasomotor, psychosocial, physical, and sexual domains in postmenopausal women. During the 12-week study period, the majority of intervention-group participants became free of moderate-to-severe hot flashes.
Study 2 details
A dietary intervention for vasomotor symptoms of menopause: a randomized, controlled trial
Neal Barnard, Hana Kahleova, Danielle Holtz, Tatiana Znayenko-Miller, Macy Sutton, Richard Holubkov, Xueheng Zhao, Stephanie Galandi, and Kenneth Setchell.
Published in Menopause Volume 30 2023
Abstract
Objective
Postmenopausal vasomotor symptoms disrupt quality of life. This study tested the effects of a dietary intervention on vasomotor symptoms and menopause-related quality of life.
Methods
Postmenopausal women (n = 84) reporting at least two moderate-to-severe hot flashes daily were randomly assigned, in two successive cohorts, to an intervention including a low-fat, vegan diet and cooked soybeans (½ cup [86 g]
daily) or to a control group making no dietary changes. During a 12-week period, a mobile application was used to record hot flashes (frequency and severity), and vasomotor, psychosocial, physical, and sexual symptoms were assessed
with the Menopause-Specific Quality of Life questionnaire. Between-group differences were assessed for continuous (t tests) and binary (χ2/McNemar tests) outcomes. In a study subsample, urinary equol was measured after the consump
tion of ½ cup (86 g) of cooked whole soybeans twice daily for 3 days.
Results
In the intervention group, moderate-to-severe hot flashes decreased by 88% ( P < 0.001) compared with 34% for the control group ( P < 0.001; between-group P < 0.001). At 12 weeks, 50% of completers in the intervention
group reported no moderate-to-severe hot flashes at all. Among controls, there was no change in this variable from base-line (χ2 test, P < 0.001). Neither seasonality nor equol production status was associated with the degree of improvement.
The intervention group reported greater reductions in the Menopause-Specific Quality of Life questionnaire vasomotor (P = 0.004), physical (P = 0.01), and sexual (P = 0.03) domains.
Conclusions
A dietary intervention consisting of a plant-based diet, minimising oils, and daily soybeans significantly reduced the frequency and severity of postmenopausal hot flashes and associated symptoms.
New York Times article – Could Certain Foods Help With Hot Flashes? (Restricted access)
See more from MedicalBrief archives:
New drug cuts number and severity of hot flushes
Managing hot flashes without hormones
No increased mortality risk from HRT — 18-year study
HRT should be given earlier as menopause ‘reshapes the brainʼ – Nature Scientific Reports
Isoflavones associated with decrease in all-cause mortality in breast cancer
Hot flashes can last up to seven years