Submitted to: Journal of Trace Elements in Experimental Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 1, 1999
Publication Date: N/A
Interpretive Summary: Anecdotal and circumstantial evidence suggests that boron supplementation can alleviate discomforts that occur during menopause. Thus, an experiment was conducted with 43 menopausal women who were experiencing hot flashes or night sweats. They were given capsules containing 2.5 mg of boron for 60 days followed or preceded by 90 days of receiving a placebo containing lactose powder. Because boron is well absorbed in the gut and quickly excreted in the urine, urinary boron was used to estimate usual dietary intake. Unexpectedly, 21 women reported that boron supplementation resulted in more frequent and severe hot flashes and night sweats. On the other hand, 10 women reported a reduction in discomforts. The remaining 15 women showed no change. Thus, boron supplementation can not be generally recommended to alleviate discomforts of menopause, but may help some women. Boron supplementation also increased an active forms of estrogen and thyroid hormone in blood. These hormones are involved in the maintenance of healthy bones. Thus, boron may be similar to other nutrients in that it can counteract some of the negative changes (for example, bone loss) that occur during and after menopause, but not generally alleviate all symptoms of menopause. Urinary boron excretion during the placebo period indicated that the usual boron intake of menopausal women in the eastern North Dakota area ranges between 0.34 and 2.33 mg/d; 16 women apparently consumed an average of less than 1.0 mg/d. It has been suggested that between 0.5 and 1.0 mg/d of boron is the lower limit of intake that assures beneficial health effects. Finding 16 of 43 women consuming less than 1.0 mg/d of boron suggests that boron may be a practical nutritional concern.
Technical Abstract: A double-blind crossover designed experiment was conducted with 43 peri- menopausal women who were experiencing discomforts associated with meno- pause. They were given capsules containing 2.5 mg of boron for 60 days followed (19 women) or preceded (24 women) by 90 d of receiving a placebo capsule containing lactose powder. Blood was collected weekly after a 12- hour overnight fast. Urine voided in 24 hours was collected 3 times each week. Because boron is well absorbed and excreted in the urine, urinary boron was used to estimate usual oral intake. Urinary boron excretion dur- ing the placebo period indicated that the usual boron intake of peri-meno- pausal women in the eastern North Dakota area of the U.S. ranges between 0.34 and 2.33 mg/d with a median of 1.15 mg/d. Usual plasma concentrations range between 0.020 and 0.067 ug/mL with a median of 0.033 ug/mL. The boron supplementation moderately increased the median plasma boron concentration to 0.052 ug/mL with a range of 0.028 to 0.075 ug/mL. Boron supplementation resulted in more frequent and severe hot flashes and night sweats in 21 women. On the other hand, 10 women reported a reduction in discomforts. The remaining 15 women did not respond negatively or positively to the boron supplementation. Boron supplementation significantly increased white blood cell numbers with a decreased percentage of lymphocytes and increased per- centage of polymorphonuclear leukocytes. The boron supplementation also affected serum 17 beta-estradiol, alkaline phosphatase and throxine con- centrations, but the effect was influenced by the sequence in which the boron supplement and placebo were given. The findings show that boron is homeostatically controlled, and support the hypothesis that boron affects hormone processes, possibly at the cell membrane level, in humans.