What causes hot flashes and how do you stop them?
Hot flashes are sudden waves of heat in the face and upper body caused by the falling and fluctuating estrogen of perimenopause and menopause. In a large US study they lasted a median of 7.4 years. Hormone therapy is the most effective treatment. Without hormones, the Menopause Society recommends cognitive behavioral therapy, clinical hypnosis, several prescription medicines and, for women with extra weight, weight loss. It does not recommend supplements, herbal remedies or soy.
Key takeaways
- A hot flash is a sudden feeling of heat in the face and upper body, lasting from seconds to several minutes.
- Night sweats are hot flashes during sleep, and they are a common reason for broken sleep.
- In the SWAN study, frequent hot flashes lasted a median of 7.4 years, longer when they started early in perimenopause.
- Hormone therapy is the most effective treatment.
- Recommended without hormones: CBT, clinical hypnosis, several prescription medicines, and weight loss for women with extra weight.
- Not recommended for hot flashes: supplements, herbal remedies, soy, and paced breathing.
- Protein during weight loss protects muscle, which matters if weight loss is part of your plan.
Hot flashes are the symptom most people associate with menopause, and for good reason: most women have them at some point. Menopause symptoms covers the rest. What is less well known is how long they can last, and how much the evidence differs between the treatments that are recommended and the ones that are sold.
What a hot flash is
A hot flash is a sudden feeling of heat that rushes to the upper body and face. It may last from a few seconds to several minutes or longer. Some women have them a few times a month, others several times a day. Hot flashes at night are called night sweats, and they can wake you up and leave you tired the next day.1 Menopause insomnia and menopause fatigue cover what that does to sleep and energy.
They come with the falling and fluctuating estrogen of perimenopause and menopause, which is why they usually start in the years around the final period.
How long hot flashes last
The best data comes from SWAN, which followed more than 3,000 US women through the menopause transition.2
| Median duration | Group | |
|---|---|---|
| All women with frequent hot flashes | 7.4 years in total | 1,449 women |
| After the final period | 4.5 years | 881 women |
| Started before or early in perimenopause | Over 11.8 years in total | Longest |
| Started after the final period | 3.4 years in total | Shortest |
The study also found that stress, anxiety and depressive symptoms at the time hot flashes began were linked with them lasting longer.2 The main message is practical: if hot flashes are affecting your life, waiting for them to pass could mean waiting years, so treatment is worth considering.
Treatments that work
Hormone therapy is the most effective treatment for hot flashes and night sweats.1 The Menopause Society says it should be considered for women within 10 years of their final period. It is not suitable for everyone, and the benefits and risks depend on your age, health and history, which is why it is a decision to make with your clinician.3
For women who cannot or prefer not to use hormones, the Menopause Society's 2023 review recommends:3
- Cognitive behavioral therapy (CBT) and clinical hypnosis, both with the strongest level of evidence.
- Prescription medicines: certain antidepressants (SSRIs and SNRIs), gabapentin, fezolinetant and oxybutynin. Your prescriber will decide which, if any, suits you.
- Weight loss, for women carrying extra weight.
Natural menopause treatments looks at the non-drug options in more detail.
What does not work, according to the evidence
The same review does not recommend these for hot flashes:3
- Supplements and herbal remedies, including black cohosh.
- Soy foods, soy extracts and the soy metabolite equol.
- Paced breathing.
- Cooling techniques and avoiding triggers, as a treatment.
- Exercise, yoga and mindfulness, as a treatment for hot flashes specifically.
Black cohosh is the best tested of the herbal options: a Cochrane review of 16 trials with 2,027 women found no difference from placebo in how often hot flashes happened.4
The last item on that list surprises people. Exercise has many benefits in midlife, for muscle, bone, heart and mood. The review simply found it does not reliably reduce hot flashes, so it should be done for those other reasons.
Where weight loss and protein come in
Weight loss is one of the few lifestyle changes the Menopause Society recommends for hot flashes, for women carrying extra weight.3 The way you lose weight matters in midlife, because muscle is already declining. In a meta-analysis of 24 trials, higher protein diets with the same calories kept about 0.4 kg more lean mass and led to slightly more fat loss than standard protein diets.5
So if weight loss is part of your plan, keep protein high while calories come down. Protein Buddy works out a daily protein target from a short quiz on your weight, age, activity and goal, and Home shows how many grams are left today as you log. Typing meals in by hand is free with no limit. The menopause diet shows what the plate looks like.
Prescription medicine for menopause explains each prescription option in plain language.
When to see a doctor
See a clinician if hot flashes or night sweats disturb your sleep or work, if you want to discuss hormone therapy or other medicines, or if night sweats come with fever, weight loss you cannot explain or other new symptoms, since these can have causes other than menopause.
More questions about Women over 40
What does a hot flash feel like?
A sudden rush of heat to the face, neck and chest, often with flushing and sweating, sometimes followed by chills. It can last from a few seconds to several minutes. Some women have them a few times a month, others several times a day.
How long do hot flashes last?
Each flash lasts seconds to minutes. The phase of life with frequent hot flashes lasted a median of 7.4 years in the SWAN study, with a median of 4.5 years after the final period. Women whose flashes began before or early in perimenopause had them longest.
What is the best treatment for hot flashes?
Hormone therapy is the most effective treatment, according to both ACOG and the Menopause Society. For women who cannot or prefer not to take hormones, cognitive behavioral therapy, clinical hypnosis and several prescription medicines are recommended. Your clinician can help you choose.
Do supplements help hot flashes?
The evidence says no. The Menopause Society's 2023 review does not recommend supplements, herbal remedies, soy foods or soy extracts for hot flashes, and a Cochrane review found black cohosh no better than placebo.
Do spicy food, alcohol or caffeine trigger hot flashes?
Some women notice they do, and it is reasonable to test that for yourself. But the Menopause Society does not recommend avoiding triggers as a treatment, because the evidence that it reduces hot flashes overall is limited.
References
- The Menopause Years
- Duration of menopausal vasomotor symptoms over the menopause transition
- The 2023 nonhormone therapy position statement of The North American Menopause Society
- Black cohosh (Cimicifuga spp.) for menopausal symptoms
- Effects of energy-restricted high-protein, low-fat compared with standard-protein, low-fat diets: a meta-analysis of randomized controlled trials
