Boron is a mineral that is not considered essential, but it may help with the metabolism of calcium, vitamin D, and estrogen. It may also play a role in bone health, brain function, reproduction, and development.
Boron is naturally present in foods such as fresh and dried fruit, nuts, legumes, and vegetables. Some beverages, including wine, cider, and beer, also contain boron.
Boron is also available as a dietary supplement in supplement stores and pharmacies, in forms such as sodium borate, chelated boron, boron citrate, and calcium fructoborate. However, it should only be used under the guidance of a doctor or registered dietitian.
Boron benefits
Possible roles of boron in the body include:
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Supporting calcium metabolism
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Helping metabolize vitamin D and sex hormones
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Helping maintain brain function, reproduction, and development
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Having anti-inflammatory effects
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Helping support bone formation and maintenance
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Reducing the risk of cancer
The World Health Organization (WHO) has concluded that boron is a “probably essential” nutrient in humans. However, this has not been conclusively proven, because no specific biochemical function of boron has been identified.
Food sources
The table below shows some foods that are high in boron:
Other foods that also contain boron include apple juice, peanut butter, nuts, beans, and green vegetables.
Recommended daily amount
Because boron is not considered an essential nutrient, there is no minimum recommended daily intake.
However, the maximum daily intake of boron varies by age, as follows:
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Children 1 to 3 years old: 3 mg per day
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Children 4 to 8 years old: 6 mg per day
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Children 9 to 13 years old: 11 mg per day
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Children 14 to 18 years old: 17 mg per day
According to the NIH Office of Dietary Supplements, adults 19 years and older should consume no more than 20 mg of boron per day. This upper intake recommendation exists to help ensure that high daily boron intake does not cause harmful health effects.
Boron supplement
Boron supplements may be available on their own, in the form of sodium borate, chelated boron, boron citrate, or calcium fructoborate, or combined with other nutrients.
These supplements may be used to help support bone formation and maintenance, reduce inflammation, improve cognitive function, and increase testosterone levels. However, there is no scientific evidence proving that boron supplements provide these health benefits.
The commonly recommended boron supplement dose is usually 3 mg per day or more. However, the dose should always be used according to a doctor’s or registered dietitian’s recommendation.
Chelated boron
Chelated boron is boron bound to an amino acid. Chelated supplements are generally used to help improve mineral absorption.
Excess boron
Very high doses of boron, accidentally consumed through chemical products such as boric acid or other borate-containing compounds, may cause nausea, gastrointestinal discomfort, vomiting, diarrhea, skin redness, rash, agitation, seizures, depression, and vascular collapse.
Excess boron may also cause headache, hypothermia, restlessness, fatigue, kidney injury, dermatitis, alopecia, anorexia, and indigestion. In infants, high boron intake may cause anemia, seizures, erythema, and thinning hair.
In addition, extremely high doses of boron can be fatal.
Boron deficiency
The symptoms caused by boron deficiency are still not well known. However, some studies suggest that boron deficiency may affect brain function by reducing mental alertness and impairing executive function.
In addition, low boron intake (0.25 mg of boron per 2,000 kcal) may increase the urinary excretion of calcium and magnesium and reduce blood estrogen levels in postmenopausal women.
Low dietary boron intake (0.23 mg of boron per 2,000 kcal) also appears to lower blood levels of calcium and 25-hydroxyvitamin D and increase calcitonin and osteocalcin levels in men and women, which may reduce bone density.