Hot flashes and night sweats (otherwise known as “vasomotor symptoms”) are incredibly common for women in their 40’s and beyond: 80% of women will experience them sometime during the menopause transition. What is highly variable is their frequency, severity and when they might begin to appear.

One study showed that:

• 18.4% of women had “early onset” hot flashes, which started 10 years before menopause
• 29.0% of women had "late onset" hot flashes, which started near menopause (average age: 51)
• 5.6% of women had early onset hot flashes PLUS persistent high frequency hot flashes until 14 years after menopause
• 27% had persistently low hot flash frequency

Because vasomotor symptoms are so incredibly common, it’s important that women know all of the options available to manage and treat them. 

This article will review the nutrition and natural medicine support for vasomotor symptoms; I will cover the use of estrogen and progesterone (bioidentical) hormone replacement therapy in detail in other articles.

Nutrition for Hot Flashes and Night Sweats

There are several different dietary factors that can either aggravate or gently reduce hot flashes and night sweats. These are the tips that I review with all my patients during their nutrition analysis in perimenopause and menopause.

Caffeine. 

I know, I know. It’s heartbreaking, I agree. But one study demonstrated that women who consume caffeine have worse vasomotor (hot flash) scores than women who did not consume caffeine.

Consider switching to decaf, downgrading to green tea, or taking a break from caffeine for 1-2 months. If you’re in the category of “caffeine worsens hot flashes,” you’ll likely notice the improvements within a month or so.

By the way, if you’re looking for more reasons to cut back: caffeine worsens the cyclic, monthly breast tenderness that can occur in the days before the period. If you’re breasts have been feeling more swollen and tender as you progress through your 40’s, going caffeine-free can help (in some cases: a lot).

Alcohol.  

I see time and time again in my practice that alcohol aggravates night sweats in perimenopausal women. Additionally, alcohol disrupts quality sleep, which in turn can aggravate vasomotor symptoms. Red wine appears to be particularly aggravating for a lot of women.

I often recommend women try 1-2 months “dry” to see how much better they feel. The majority quickly notice improved sleep, fewer and less intense night sweats, improved energy, better mood and clearer mind. If this sounds daunting, consider going alcohol-free Sunday to Friday, and indulging in 1-2 servings per evening over the weekend.

Other (possible) trigger foods. 

Certain foods may trigger hot flashes in some women. Everyone is different; start by noticing any association between your intake of these foods and timing of your hot flashes:

• Spicy foods
• Alcohol
• Coffee and caffeine (including black tea and soda)
• Hot beverages
• Foods containing histamine (including cheese, red wine)

Increase your intake of organic, ideally fermented, soy products.

There is a lot of confusion out there about soy products and hormone health, so let me clarify. For starters, soy contains isoflavones (called genistein and daidzein) that have mild, weak estrogen-like qualities. These compounds have the ability to activate estrogen receptors when concentrations of estrogen are low (think: menopause). Conversely, isoflavones can ALSO ‘block’ estrogen receptors when estrogen levels are too high (think: estrogen dominance).

This means that soy is an excellent food for women struggling with low estrogen, high estrogen or BOTH – as is the case in perimenopause when estrogen is fluctuating wildly!

Need more convincing that incorporating more soy into your diet is a good move? Several systematic reviews have demonstrated that diets high in soy, fermented soy products and soy isoflavones can:

• Reduce cardiovascular mortality (death)
• Reduce risk of ovarian, prostate, gastric, colorectal, lung and even breast cancer
• Benefit metabolism, bones and muscles, kidney function, cognitive function and mood, particularly in perimenopausal women.

It appears that it takes a minimum of 13 weeks after increasing soy intake to notice the improvements in your symptoms. This means that adding soy is an excellent part of a long term strategy to reduce hot flashes (and support your overall health in all the other ways mentioned above).

Here are some ideas to help incorporate more soy into your nutrition routine:

• Have more vegetarian meals that incorporate organic tofu or tempeh.
• Marinating then frying tofu is an excellent addition to a vegetable stir fry.
• Try using a block of soft tofu as the protein base for your daily green smoothie. It lends an excellent smooth texture, has no flavour, and also happens to be high in calcium.
• Use miso as a base for sauces, dressings, vegan gravy, or as a soup base.
• Incorporate natto (fermented soybeans) into rice bowls or rice dishes.
• Have edamame as an easy and delicious snack or addition to buddha bowls.
• Use organic soy milk as your go-to milk alternative.

Add more phytoestrogen-rich foods to your diet.

Soy is one of the best phytoestrogens, as described above. Other sources of dietary phytoestrogens include:

• Chickpeas, lentils (contain genistein and daidzein)
• Flaxseed, grains, fruits and vegetables (lignans)

The Best Supplements for Hot Flashes

Black cohosh (Cimicifuga racemosa)

A handful of studies have examined the use of black cohosh for hot flashes. The Spanish Menopause Society states that “the most common dose of 40mg per day is capable of achieving a significant reduction in hot flushes (particularly in women with intense hot flushes) and an improvement in mood.

Black cohosh is one of my favourite herbs for perimenopause and menopause symptoms.  It pairs really well with valerian (to support sleep), rhodiola (for fatigue, overwhelm and/or depression), sage (for hot flashes and night sweats) or St John’s Wort (low mood or depression).

Phytoestrogen extracts.

As discussed above, phytoestrogens are helpful for hot flashes, and they can also be taken in supplement form.  In one study, a dose of 54mg per day for a minimum of 6 weeks reduced frequency of hot flashes by 20.6% and severity by 26.2% compared to placebo.  Most studies look at doses of 60-112mg per day for at least 12 weeks. Look for supplements that provide over 18.8mg of genistein, which is twice as effective at reducing hot flash frequency compared to lower dose genistein.

Milk thistle (Silybum marianum).

One study showed that taking 400mg per day reduced the frequency of hot flashes from 4.32 to 0.2 episodes per day.  It also reduced the severity from of hot flashes from 5.25 to 1.62 within 12 weeks.

Lifestyle Support & Other Treatments for Hot Flashes

Certain lifestyle habits can also help or hinder your hot flashes and night sweats.  Here are my top evidence-based tips for reducing hot flashes:

Quit smoking. 

Women who smoke have worse hot flashes compared to non-smokers. 

Get active.

Being physically active helps to reduce hot flashes.

More specifically, take up weight training. 

One small study found that the women who engaged in 3x weekly weight training sessions (duration: 45min) experienced fewer hot flashes daily compared to the control group.

Increase your resilience to stress.

Stress has been demonstrated to worsen a woman’s vasomotor symptoms. More most women, the balancing act of motherhood, career, caretaking and/or partnership is highly stressful.

Cool down your sleep environment. 

Mild hot flashes may be simply managed by reduce bedroom temperature, use fans at night, and/or wearing light pyjamas.  

Track your symptoms and your cycle.

Okay, this won't reduce your hot flashes BUT it will help you and your health care provider to identify patterns and timing of your symptoms.  This is the first thing I have patients begin, if they haven't already started.

Acupuncture. 

A few studies have demonstrated that acupuncture can be helpful for reducing vasomotor symptoms.  A minimum of 3 sessions is required, with optimal benefits after 8 sessions.  Best results occur when acupuncture is delivered more frequently over the first 8 weeks (approximately once a week). 

Hormone Replacement Therapy (HRT)

Without a doubt, the best researched, most effective, fastest treatment to control hot flashes and night sweats is estrogen therapy. This is a topic that I discuss with ALL of my perimenopause and menopause patients, whether or not they choose to ever go on HRT.  

Furthermore, bioidentical progesterone therapy (otherwise known as oral micronized progesterone) on its own has been shown to help reduce hot flashes and night sweats during perimenopause. Progesterone is also excellent for reducing PMS symptoms, supporting mood (particularly reducing anxiety), reducing heavy periods and enhancing sleep quality during perimenopause.

Women are not getting enough good quality, reliable information about HRT as a possible option for their health and wellness. For this reason, I spend lots of time here with my patients in their 40's and 50's.

This specific topic will be a whole series of articles unto themselves, so suffice to say for now, if you haven’t explored this option with your healthcare provider, I recommend at least having the conversation.

Just make sure you are working with a doctor or ND who has done additional training and is well versed in HRT.

A thorough discussion about whether to go on HRT cannot adequately be covered within a 5-10 minute doctor's visit.  A thorough assessment of a woman's hormone status, needs, suitability and medical history should be covered in detail as part of an informed discussion about HRT.  

The discussions I have with my patients to explore HRT look something like this:

1. Detailed review of her perimenopause or menopause symptoms, using my 54-point hormone assessment
2. Discussion about her current health care goals (ex. control hot flashes and sleep better), and long term goals (ex. osteoporosis prevention, protect cognitive function, optimize body composition)
3. Discussion about her current understanding, beliefs and concerns about HRT
4. Review of her medical history and medications
5. Review of her blood tests from the last 6 months (or get updated testing done)
6. Short physical exam
7. Review of her family history
8. Review of her cardiovascular risk factors and breast cancer risk factors 
9. Thorough discussion about HRT, myth-busting, answering questions and concerns, discussing whether HRT is an option for her, exploring other options available to her
10. If HRT is desired:  Prescribe, and discuss plan for reassessing and monitoring her progress every 1-3 months.

This typically takes place over the course of 1-2 visits. 

In my opinion, ALL women in midlife should be offered the time and space to have this discussion.  

Dr. Kathleen Mahannah is Naturopathic Doctor licensed by the College of Naturopathic Physicians of British Columbia.  Her practice focusses in women's health and hormone balancing using natural medicine and Hormone Therapy, particularly for women in perimenopause and menopause. Dr. Mahannah completed a Degree in Physical Education and Health from University of Toronto, and Diploma of Exercise Science from Capilano College, before obtaining her Diploma of Naturopathic Medicine. She has been practicing for over 6 years in North Vancouver, BC, Canada. Learn more about Dr. Mahannah here.

References

Faubion SS, Sood R, Thielen JM, Shuster LT. Caffeine and menopausal symptoms: what is the association? Menopause. 2015 Feb;22(2):155-8. doi: 10.1097/GME.0000000000000301. PMID: 25051286.

Avis NE, Coeytaux RR, Isom S, Prevette K, Morgan T. Acupuncture in Menopause (AIM) study: a pragmatic, randomized controlled trial. Menopause. 2016 Jun;23(6):626-37. doi: 10.1097/GME.0000000000000597. PMID: 27023860; PMCID: PMC4874921.

Li N, Wu X, Zhuang W, Xia L, Chen Y, Zhao R, Yi M, Wan Q, Du L, Zhou Y. Soy and Isoflavone Consumption and Multiple Health Outcomes: Umbrella Review of Systematic Reviews and Meta-Analyses of Observational Studies and Randomized Trials in Humans. Mol Nutr Food Res. 2020 Feb;64(4):e1900751. doi: 10.1002/mnfr.201900751. Epub 2019 Oct 14. PMID: 31584249.

Taku K, Melby MK, Kronenberg F, Kurzer MS, Messina M. Extracted or synthesized soybean isoflavones reduce menopausal hot flash frequency and severity: systematic review and meta-analysis of randomized controlled trials. Menopause. 2012 Jul;19(7):776-90. doi: 10.1097/gme.0b013e3182410159. PMID: 22433977.

Saberi Z, Gorji N, Memariani Z, Moeini R, Shirafkan H, Amiri M. Evaluation of the effect of Silybum marianum extract on menopausal symptoms: A randomized, double-blind placebo-controlled trial. Phytother Res. 2020 Dec;34(12):3359-3366. doi: 10.1002/ptr.6789. Epub 2020 Aug 6. PMID: 32762030.

Berin E, Hammar M, Lindblom H, Lindh-Åstrand L, Rubér M, Spetz Holm AC. Resistance training for hot flushes in postmenopausal women: A randomised controlled trial. Maturitas. 2019 Aug;126:55-60. doi: 10.1016/j.maturitas.2019.05.005. Epub 2019 May 14. PMID: 31239119.

Shahnazi M, Nahaee J, Mohammad-Alizadeh-Charandabi S, Bayatipayan S. Effect of black cohosh (cimicifuga racemosa) on vasomotor symptoms in postmenopausal women: a randomized clinical trial. J Caring Sci. 2013 Jun 1;2(2):105-13. doi: 10.5681/jcs.2013.013. PMID: 25276716; PMCID: PMC4161092.

Mohammad-Alizadeh-Charandabi S, Shahnazi M, Nahaee J, Bayatipayan S. Efficacy of black cohosh (Cimicifuga racemosa L.) in treating early symptoms of menopause: a randomized clinical trial. Chin Med. 2013 Nov 1;8(1):20. doi: 10.1186/1749-8546-8-20. PMID: 24499633; PMCID: PMC4029542.

Castelo-Branco C, Navarro C, Beltrán E, Losa F, Camacho M; on the behalf of the Natural Products Study Group of the Spanish Menopause Society. Black cohosh efficacy and safety for menopausal symptoms. The Spanish Menopause Society statement. Gynecol Endocrinol. 2022 May;38(5):379-384. doi: 10.1080/09513590.2022.2056591. Epub 2022 Apr 11. PMID: 35403534.

Hitchcock C, Prior J. Oral micronized progesterone for vasomotor symptoms-a placebo-controlled randomized trial in healthy postmenopausal women. Menopause 2012;19(8):886-893.

Briese V, Stammwitz U, Friede M, Henneicke-von Zepelin HH. Black cohosh with or without St. John's wort for symptom-specific climacteric treatment--results of a large-scale, controlled, observational study. Maturitas. 2007 Aug 20;57(4):405-14. doi: 10.1016/j.maturitas.2007.04.008. Epub 2007 Jun 21. PMID: 17590291.

Arnot M, Emmott EH, Mace R. The relationship between social support, stressful events, and menopause symptoms. PLoS One. 2021 Jan 27;16(1):e0245444. doi: 10.1371/journal.pone.0245444. PMID: 33503073; PMCID: PMC7840006.