Boron supplement and bone metabolism in six postmenopausal women
What it found
Adding 3 mg of boron daily for 3 weeks did not change minerals, sex hormones or bone turnover markers in six postmenopausal women.
The low-boron diet itself caused the body to take in and pass out more calcium.
What they found
Studies in people
No effect from supplement
Raising boron intake from 0.33 to 3.33 mg per day made no difference to minerals, sex hormones or bone turnover markers in these six women.
Calcium handling changed
Switching to the low-boron diet quickly raised calcium in the urine, sometimes more than doubling it. This high level stayed the same even when the women took the boron supplement.
Hormone levels unchanged
Blood testosterone levels varied between the women but did not change with extra boron. Oestrogen levels were very low and hard to measure accurately.
Bone turnover steady
Urine markers that show how fast bone is breaking down stayed about the same across all 6 weeks. Adding boron did not alter them.
Boron absorbed quickly
Most of the boron taken in was passed out in the urine within a day or two. When the supplement started, over 90% of the boron taken in appeared in the urine.
What the authors conclude
- They found no effect of a daily 3 mg boron supplement on bone minerals, bone turnover or sex hormone levels in postmenopausal women.
- They suggest the low-boron diet itself changed how the body handled calcium, which may have hidden any effect the supplement could have had.
How it was done
Earlier work suggested that raising boron intake might boost sex hormones and lower calcium loss in urine after menopause. The authors wanted to check if a boron supplement could affect bone mineral handling and hormone levels.
Six healthy postmenopausal women lived in a research unit for 6 weeks. They ate a diet very low in boron (0.33 mg per day) for 3 weeks, then took a 3 mg boron supplement daily for another 3 weeks. Researchers measured minerals, hormones and bone markers in blood and urine throughout.
What it can’t tell you
- With only six women, this trial cannot show what would happen in a larger group.
- The study lasted just 6 weeks, so longer-term effects remain unknown.
- The unusual diet used here may not reflect what happens when people eat their normal food.
Who paid
- Authors work at
- Rowett Research Institute, Aberdeen
The paper
- Title
- The influence of a low-boron diet and boron supplementation on bone, major mineral and sex steroid metabolism in postmenopausal women
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Beattie JH, Peace HS (1993). The influence of a low-boron diet and boron supplementation on bone, major mineral and sex steroid metabolism in postmenopausal women. The British journal of nutrition. doi:10.1079/bjn19930087Free full textPubMed 8329361DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error