Vitamin E for Hot Flashes

Vitamin E is a weak option for hot flashes: in the best-designed trial it shaved off about one a day, and the pooled evidence shows no reliable effect. A 2022 meta-analysis found vitamin E alone did not significantly reduce hot flash frequency compared with placebo (SMD -0.21, 95% CI -0.47 to 0.04) (Maghalian 2022). In the largest placebo-controlled trial, 800 IU a day gave about one fewer hot flash a day than placebo, a result the authors called marginal, and women were no more likely to prefer vitamin E than placebo (Barton 1998).

Two small 8-week trials from the same Iranian research group found fewer hot flashes with 200 IU once or twice a day (Ataei-Almanghadim 2020; Yousefi-Nodeh 2024), which is why the picture is mixed rather than flatly negative. But the 2023 Menopause Society statement does not recommend supplements and herbal remedies for hot flashes, and French guidelines list vitamin E among the approaches that appear ineffective (NAMS 2023; Raccah-Tebeka 2021).

There is no established reason vitamin E would cool hot flashes. One Iranian trial team started from the idea that falling estrogen at menopause triggers oxidative stress and inflammation that drive symptoms, so an antioxidant might help. In their 84-woman trial, total antioxidant capacity rose in the vitamin E group (P = 0.006) (Farshbaf-Khalili 2022). A 2022 review gives a different rationale, describing vitamin E components as phytoestrogens (Feduniw 2022).

A change in a blood marker isn't fewer hot flashes. In the same trial in which antioxidant capacity rose, vasomotor scores fell in every group, placebo included, and the only symptom that improved more with vitamin E than placebo was anxiety (P = 0.026) (Farshbaf-Khalili 2022).

The placebo response is large in hot flash trials. In the largest trial, hot flash frequency fell 25% on vitamin E and 22% on placebo during the first period (P = .90) (Barton 1998). Any small change you notice on vitamin E may be that placebo effect.

Trials gave vitamin E by mouth at 200 IU a day (Ataei-Almanghadim 2020), 200 IU twice a day (Yousefi-Nodeh 2024), 400 IU a day (Ziaei 2007) and 800 IU a day (Barton 1998). There is no sign that more works better: the 800 IU trial had one of the weakest results. A meta-analysis of 19 trials found that 400 IU a day or more was linked to higher all-cause mortality, with risk rising above 150 IU a day, and advised avoiding high doses (Miller 2005).

In the trial that checked at both 4 and 8 weeks, vitamin E only beat placebo at 8 weeks (P = 0.029; P = 0.052 at 4 weeks) (Ataei-Almanghadim 2020). If you try it, don't exceed 200 IU a day, the lowest dose tested, and judge it at 8 weeks; even that dose is above the level where mortality risk began to rise.

A 2022 systematic review included 10 trials (1,100 participants) of vitamin E, omega-3 or both. For vitamin E alone, the pooled reduction in hot flash frequency was not significant (SMD -0.21, 95% CI -0.47 to 0.04). Vitamin E combined with omega-3 reduced intensity in two studies (MD -0.35, 95% CI -0.48 to -0.21), and no serious side effects were reported (Maghalian 2022).

The largest placebo-controlled trial was a double-blind crossover in breast cancer survivors: 4 weeks of 800 IU a day and 4 weeks of placebo, in random order. The crossover analysis found about one fewer hot flash a day with vitamin E (P ≤ .05), which the authors judged clinically marginal, and at the end 32% preferred vitamin E and 29% placebo (Barton 1998).

Two triple-blind trials from the same Iranian research group found fewer hot flashes than placebo after 8 weeks. In 93 women, 200 IU a day lowered the mean number of hot flashes (adjusted mean difference -8.7, 95% CI -0.6 to -15.0, P = 0.029) (Ataei-Almanghadim 2020). In 84 women, 200 IU twice a day cut hot flashes by nearly a third of the baseline amount (P = 0.002) (Yousefi-Nodeh 2024).

An older double-blind trial in 51 women found lower severity scores and fewer daily hot flashes (3.19 vs 5.00) after 400 IU a day than after placebo (P < 0.0001) (Ziaei 2007). As its abstract describes it, everyone took placebo first and vitamin E second, so time and order could account for part of the difference. A 2022 systematic review that read these trials more favourably still concluded that estrogen works better (Feduniw 2022).

In 115 women with breast cancer randomised to gabapentin or vitamin E, gabapentin cut hot flush frequency by 57.05%; vitamin E cut it by 10.02%, which was not significant, and 34.78% of the vitamin E group dropped out because it didn't work (Biglia 2009). A Cochrane review of 16 trials of non-hormonal treatments after breast cancer found the one vitamin E trial showed no benefit, while SSRIs and SNRIs, clonidine and gabapentin reduced hot flushes (Rada 2010).

The trials that report their length gave vitamin E for 4-8 weeks, most are small, and the clearly positive ones come from a single country. The meta-analysis authors called for larger trials (Maghalian 2022). For now, the Menopause Society's 2023 statement does not recommend supplements and herbal remedies for hot flashes (NAMS 2023).

In the trials themselves vitamin E was well tolerated: no toxicity was seen in 120 women taking 800 IU a day for 4 weeks (Barton 1998), and the 2022 meta-analysis found no serious side effects reported (Maghalian 2022). The concern is longer-term, high-dose use. In a meta-analysis of 19 trials, doses of 400 IU a day or more were linked to 39 extra deaths per 10,000 people (95% CI 3 to 74), mostly in trials of people with chronic disease (Miller 2005). In another, vitamin E raised the risk of haemorrhagic stroke by 22% (Schürks 2010).

Two of the hot flash trials on this page were in women after breast cancer (Barton 1998; Biglia 2009). If you take tamoxifen, French guidelines say to avoid medicines that interact with CYP2D6, which rules out some antidepressants used for hot flashes (Raccah-Tebeka 2021), so treatment choices are best made with your oncology team.

The main interaction concern is bleeding. In a small double-blind trial of 21 people on warfarin, vitamin E did not change INR (Kim 1996), but in 566 people on warfarin, higher blood vitamin E levels predicted bleeding events (Pastori 2013). The NIH Office of Dietary Supplements notes that vitamin E can inhibit platelet aggregation and oppose vitamin K-dependent clotting factors, so large doses taken with anticoagulant or antiplatelet medicines can raise bleeding risk. It also notes that oncologists generally advise against antioxidant supplements during chemotherapy or radiotherapy, because they might make these treatments less effective (NIH ODS). No trial on this page reported interactions with hot flash medicines.