A trial described in an article in the September, 2010 issue of the journal Gynecological Endocrinology found that the B vitamin folic acid significantly reduced the number and intensity of hot flashes experienced by a group of menopausal women.
Hot flashes, characterized by an unpleasant sensation of excessive heat, occur in up to 75 percent of menopausal women and are linked to a reduction in estrogen levels. While hormone replacement therapy is helpful in alleviating hot flashes, some women prefer to avoid it.
Brain release of the hormone norepinephrine (noradrenaline) and its metabolite 3-methoxy 4-hydroxy phenyl glycol (MHPG) have been found to be higher in women who experience hot flashes than in those who do not. Based on the findings of other research, Ayman A. A. Ewies of The Ipswich Hospital NHS Trust in Suffolk, England and colleagues “hypothesised that folic acid could ameliorate hot flushes by interacting with monoamine neurotransmitters in the brain; therefore, this study was conducted to examine the effect of folic acid supplementation on the occurrence of hot flushes and the plasma level of MHPG in postmenopausal women.”
The researchers divided 46 women suffering from hot flashes to receive 5 milligrams folic acid or a placebo daily for four weeks. Plasma MHPG levels were measured before and after treatment. Nine of the women (39.1 percent) who received folic acid experienced complete elimination of hot flashes, and 6 (21 percent) had moderate improvement. In the placebo group, only 1 woman experienced a complete response, while 84.2 percent had no benefit. Participants who received folic acid also experienced a corresponding reduction in plasma MHPG compared to levels measured in those who received the placebo. A review of the participants 2 weeks after the end of the treatment period found that hot flashes returned in all subjects who had experienced improvement when supplementing with folic acid.
“To our knowledge, this is the first study to report the effect of folic acid supplementation on hot flushes in postmenopausal women,” the authors announce. “Our study suggests that short-term supplementation with folic acid causes subjective improvements of hot flushes in some postmenopausal women probably by lowering the increased central noradrenergic activity as indicated by the reduced plasma level of its metabolite.”
“Although the data are encouraging, the long-term merits of folic acid and the ideal dosage have to be assessed in a multi-centre, randomised, placebo-controlled trial of appropriate size and duration,” they add.