Submitted to: North Dakota Academy of Science Proceedings
Publication Type: Proceedings
Publication Acceptance Date: April 1, 1996
Publication Date: N/A
Interpretive Summary: Boron is a mineral element found in food that apparently is needed for the proper utilization of calcium for such things as healthy bones. On the other hand, too high intakes of boron can lead to unhealthy changes in bone. Dietary boron is well absorbed from the gut and excreted in the urine; as a result, urinary boron is a good indicator of dietary boron intake. Thus, it is important to know the normal amounts of boron in blood and urine because a change in these values might indicate an inadequate or excessive intakes of boron. Thus, a study was performed to determine plasma boron concentrations and the amounts of boron excreted in the urine with the consumption of self-selected diets, and to see if a small supplement of boron would affect the values obtained. The findings indicated that the usual boron intakes of perimenopausal women in the eastern North Dakota area range between 0.34 and 2.33 mg/day with a median of 1.15 mg/day. Plasma boron concentrations with these types of intakes ranged between 0.020 and 0.067 with a median of 0.033 ug/ml; these probably should be considered normal. Boron supplementation increased the plasma concentration and urinary excretion of boron. The findings indicate that measurement of urinary and plasma boron may be useful in assessing boron intakes and status.
Technical Abstract: A study was performed in which objectives included the determination of plasma boron concentrations and urinary boron excretion of people consuming self-selected diets, and the effect of dietary supplementation of physiological amounts of boron on these variables. The study was a double-blind crossover design with 43 healthy perimenopausal women given sodium borate capsules containing 2.5 mg boron (analyzed) for 60 days followed (19 women) or preceded (24 women) by 90 days when they received a placebo capsule containing lactose powder. Blood was collected weekly via venipuncture after a 12-hour fast. Urine voided in 24 hours was collected three times a week. The findings indicated that dietary boron is well absorbed and excreted in the urine. Subtracting the mean urinary boron excretion with the placebo treatment from that with the boron supplement treatment yielded 2.1 mg, which is 84% of the 2.5 mg boron supplement. Thus, urinary boron was considered an indicator of boron intake. The findings during the placebo period indicate that the usual boron intake of perimenopausal women in the eastern North Dakota area ranges between 0.34 and 2.33 mg/day with a median of 1.15 mg/day. Plasma boron concentrations with these types of intakes ranged between 0.020 and 0.067 ug/ml with a median of 0.033 ug/ml; these probably should be considered normal. Boron supplementation resulted in a moderate increase in plasma boron concentrations. The findings indicate that the measurement of urinary and plasma boron may be useful in assessing boron intakes and status.