Long blog warning: I wish I could be more like the Dadaist Marcel Duchamp, who once offered: I shall be so brief that I am now done!
There are a wide variety of options for those with hot flashes. These may be conveniently divided into pharmaceuticals, neutraceuticals, surgical ones (stellate ganglion blacked). Complementary/behavioral therapies include acupuncture, exercise, yoga, and others. In today’s blog, we will look at neutraceuticals. Neutraceuticals include herbal remedies, vitamins, and phytoestrogens.
Herbals: Black cohosh is an herb made from a North American perennial plant, and has been well-studied among women with menopausal symptoms (bit not for men with prostate cancer). Black cohosh is not estrogenic, instead acting on serotonin receptors. A study of studies (meta-analysis) showed that in 6 of 9 randomized trials, black cohosh as the potential to reduce hot flashes. But, more recent trials show no effectiveness among women without cancer. Potential side effects include mild gastrointestinal upset, headaches, vomiting, and dizziness at higher doses.
St. John’s Wort is a perennial herb from Europe, and has been reported to have anti-depressant properties. Most of the studies regarding hot flashes have been limited to women experiencing natural or surgical menopause. The data is mixed on its efficacy. Because it can activate certain enzymes (called cytochrome P450 enzymes), you must check with your health care provider before taking it.
Vitamins: Vitamin E has been investigated for hot flashes: There have been 3 randomized trials, and to me it seems that vitamin E has minimal efficacy. It appears to reduce the number of hot flashes per day by only 1 to 2. A study of studies (meta-analysis) of 57 trials showed no relationship between death rates (all-cause mortality) and vitamin E. Those with heart disease, diabetes, and high blood pressure should take heed. And there is some concern about a possible increase in cancer incidence. Multivitamins with minerals may help hot flashes improve for a few months, but the advantage over placebo disappears by the 3 month mark. Folic acid is under investigation, but there are some hints that it may reduce hot flashes by reducing levels of a byproduct of norepinephrine.
Phytoestrogens: Soy products have been analyzed in a meta-analysis of 19 randomized controlled trials of soy isoflavones. Soy did appear to reduce hot flashes, when compared to a placebo. The median dose across the studies was 54 mg. The effects on men are not clear, but at least one report has not shown a benefit among men with prostate cancer. And the safety for men has not been established.
Similar to soy, red clover results have not been especially impressive. A recent randomized trial of black cohosh, red clover, placebo, and hormone therapy showed red clover didn’t work (at a dose of 398 mg per day). Among men, it has not been well-studied. Flax seed is a rich source of lignans. Three randomized trials have shown no benefit for hot flashes (women). It has not been well-investigated among men.
My take: For these interventions, differences in information about product purity, dosing, and side effects makes comparisons across studies difficult. Unfortunately, there is a lack of standardization (the US Food and Drug Administration) has minimal oversight. Multivitamins with minerals may temporarily improve symptoms, and soy seems to have some activity against hot flashes in women. For many, neutraceutical do not have the desired reduction in hot flash frequency or severity. Next, we’ll turn to surgical therapies such as a stellate ganglion block. Hint: It may work(!), but the data is limited.
The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.
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Reference: Fisher WI et al. CA: A Journal for Clinicians, vol 63 (3).