Other Name(s):

Acide Borique, Anhydride Borique, Atomic number 5, B (chemical symbol), B (symbole chimique), Borate, Borate de Sodium, Borates, Bore, Boric Acid, Boric Anhydride, Boric Tartrate, Boro, Numéro Atomique 5, Sodium Borate.


Boron is a mineral that is found in food and the environment. People take boron supplements as medicine.

Boron is used for building strong bones, treating osteoarthritis, as an aid for building muscles and increasing testosterone levels, and for improving thinking skills and muscle coordination.

Women sometimes use capsules containing boric acid, the most common form of boron, inside the vagina to treat yeast infections.

People also apply boric acid to the skin as an astringent or to prevent infection; or use it as an eye wash.

Boron was used as a food preservative between 1870 and 1920, and during World Wars I and II.

How does it work?

Boron seems to affect the way the body handles other minerals such as magnesium and phosphorus. It also seems to increase estrogen levels in older (post-menopausal) women and healthy men. Estrogen is thought to be helpful in maintaining healthy bones and mental function. Boric acid, a common form of boron, can kill yeast that cause vaginal infections.

Uses & Effectiveness

Likely Effective for...

  • Boron deficiency. Taking boron by mouth prevents boron deficiency.

Possibly Effective for...

  • Vaginal infections. Some research shows that boric acid, used inside the vagina, can successfully treat yeast infections (candidiasis), including infections that do not seem to resolve with other treatments. However, the quality of this research is in question.

Possibly Ineffective for...

  • Athletic performance. Taking boron by mouth does not seem to improve body mass, muscle mass, or testosterone levels in male bodybuilders.

Insufficient Evidence to Rate Effectiveness for...

  • Improving thinking and coordination in older people. There is some early evidence that taking boron by mouth might improve cognitive function and the ability to coordinate small muscle movements (fine motor skills) in older people.
  • Osteoarthritis. Developing research suggests that boron might be useful for decreasing symptoms of osteoarthritis.
  • Osteoporosis. Early research suggests that taking boron by mouth daily does not improve bone mass density in postmenopausal women.
  • Increasing testosterone.
  • Other conditions.
More evidence is needed to rate the effectiveness of boron for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).


Vitamin D Deficiency: How Much Vitamin D Is Enough? See Slideshow

Side Effects

Boron is LIKELY SAFE for adults and children when used in doses less than the Upper Tolerable Limit (UL) (see dosage section below). There is some concern that doses over 20 mg per day, the UL for adults, might harm a man's ability to father a child.

Boric acid, a common form of boron, is LIKELY SAFE when used vaginally for up to six months. It can cause a sensation of vaginal burning.

Boron is POSSIBLY UNSAFE for adults and children when taken by mouth in high doses. Large quantities of boron can cause poisoning. Signs of poisoning include skin inflammation and peeling, irritability, tremors, convulsions, weakness, headaches, depression, diarrhea, vomiting, and other symptoms.

Also, boric acid powder, a common form of boron, is POSSIBLY UNSAFE when applied in large amounts to prevent diaper rash.

Special Precautions & Warnings

Pregnancy and breast-feeding: Boron is LIKELY SAFE for pregnant and breast-feeding women age 19-50 when used in doses less that 20 mg per day. Pregnant and breast-feeding women age 14 to 18 should not take more than 17 mg per day. Taking boron by mouth in high doses is POSSIBLY UNSAFE while pregnant and breast feeding. Higher amounts may be harmful and should not be used by pregnant women because it has been linked to birth defects. Intravaginal boric acid has been associated with a 2.7- to 2.8-fold increased risk of birth defects when used during the first 4 months of pregnancy.

Hormone-sensitive condition such as breast cancer, uterine cancer, ovarian cancer, endometriosis, or uterine fibroids: Boron might act like estrogen. If you have any condition that might be made worse by exposure to estrogen, avoid supplemental boron or high amounts of boron from foods.

Kidney disease or problems with kidney function: Do not take boron supplements if you have kidney problems. The kidneys have to work hard to flush out boron.


EstrogensInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Boron might increase estrogen levels in the body. Taking boron along with estrogens might cause too much estrogen in the body.


Next to red peppers, you can get the most vitamin C from ________________. See Answer


The following doses have been studied in scientific research:


  • There is no Recommended Daily Allowance (RDA) for boron since an essential biological role for it has not been identified. People consume varying amounts of boron depending on their diet. Diets considered to be high in boron provide approximately 3.25 mg of boron per 2000 kcal per day. Diets considered to be low in boron provide 0.25 mg of boron per 2000 kcal per day.

    The Tolerable Upper Intake Level (UL), the maximum dose at which no harmful effects would be expected, is 20 mg per day for adults and pregnant or breast-feeding women over 19 years of age. For adolescents 14 to 18 years of age and pregnant or breast-feeding women 14 to 18 years of age, the UL is 17 mg per day. For children 9 to 13 years old, the UL is 11 mg per day; children 4 to 8 years old, 6 mg per day; and children 1 to 3 years old, 3 mg per day. A UL has not been established for infants.

  • For vaginal infections: 600 mg of boric acid powder once or twice a day.
  • For prevention of recurring Candida (yeast) infections: 600 mg twice weekly.

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