Boron Benefits for Men: Testosterone, Joints, Dosage and Safety

Short answer: The main boron benefits for men that research supports are modest and early: a tiny one-week study found that 10 mg a day raised free testosterone and lowered estradiol and inflammatory markers, while a 7-week trial in bodybuilders using 2.5 mg a day found no effect on testosterone, muscle or strength. Boron may also help joint comfort and mineral balance, but human trials are small and short. Most men get about 1 mg a day from food, and the safe upper limit for adults is 20 mg a day.

Key Takeaways

• Boron is a trace mineral found mostly in fruit, nuts, beans and coffee. It is not officially classified as an essential nutrient, so there is no RDA.
• The testosterone evidence comes from one small study of 8 men taking 10 mg a day for one week. A larger, longer trial at 2.5 mg a day found no testosterone, muscle or strength benefit.
• The best supported uses are joint comfort and lower inflammatory markers, based on short trials of 1.5 to 6 mg a day.
• Typical supplements provide 0.15 to 6 mg. The adult Tolerable Upper Intake Level is 20 mg a day from all sources.
• Boron from food is very safe. Poisoning cases involve boric acid or borax products, not dietary boron.

What Is Boron?

Boron is a trace element present in soil, water and plants, where it forms part of plant cell walls. The NIH Office of Dietary Supplements notes that boron has no clearly established biological function in humans and is not classified as an essential nutrient, which is why there is no Recommended Dietary Allowance or Daily Value for it.^[1] The World Health Organization considers 1 to 13 mg a day an acceptable safe range for adults.^[1]

Your gut absorbs about 85 to 90 percent of the boron you eat, mostly after it is converted to boric acid. It does not build up in most tissues (bone, nails and hair hold the most) and the kidneys clear it through urine, which is how the body keeps blood levels steady.^[1]

How much boron do men get from food?

Median dietary intake for adults in the United States is about 0.87 to 1.35 mg a day, and food plus supplements together come to roughly 1.0 to 1.5 mg a day.^[1] Coffee, milk, apples, beans and potatoes are major contributors in the American diet, simply because people consume them often. Men who eat little fruit, nuts or legumes sit at the low end of that range.

Boron Benefits for Men: What the Evidence Shows

Boron is popular in men’s health circles because of claims about testosterone. The reality is that the human research is thin, and the results point in different directions. Here is what the studies actually found.

Boron and testosterone (human studies)

The study most often quoted is a small trial published in Physiology and Pharmacology. Eight male volunteers took a placebo on day 0, a single 10 mg boron capsule on day 1, then 10 mg daily for a week. After one week, plasma free testosterone went up and estradiol went down, and several testosterone ratios rose. Dihydrotestosterone, cortisol and vitamin D showed small increases that were not statistically significant.^[3] The authors described it as the first human study to report higher free testosterone after boron supplementation.

That is interesting, but it has major limits: only 8 men, no separate control group, and just seven days of follow-up. It tells us something may happen in the short term, not that it lasts or that men feel any different.

An earlier randomized, placebo-controlled trial at Auburn University gave 10 male bodybuilders 2.5 mg of boron daily and 9 others a placebo for 7 weeks. Both groups gained total testosterone, lean body mass and strength from training, and the authors concluded that boron affected these outcomes “not at all.”^[4] The dose was lower than in the later study, which may partly explain the difference, but it is a clear reminder that boron is not a muscle or strength supplement.

Examine.com sums up the state of play: boron is claimed to increase testosterone at doses above dietary intake, but research is lacking, and any hormonal effect may be a byproduct of its anti-inflammatory action.^[2] If you want to know where your own levels stand, a blood test is the only reliable way. Our guides to normal testosterone levels and signs of low testosterone explain what to ask your doctor.

Inflammation and joint comfort

This is where the human data are more consistent, although still small. According to the NIH fact sheet:^[1]

• A double-blind, placebo-controlled trial in 60 adults aged 59 to 68 found that 1.5, 3 or 6 mg a day for two weeks significantly reduced inflammatory markers.
• Another double-blind trial in 60 adults with a mean age of 50 found that 6 mg a day for two weeks reduced knee discomfort.
• A pilot study of 20 people around age 65 found that 6 mg a day for 8 weeks reduced osteoarthritis symptoms compared with placebo.

The trial authors themselves say more controlled studies are needed. A 2015 review in Integrative Medicine lists lower hs-CRP and TNF-alpha among boron’s reported effects, along with roles in magnesium absorption and the handling of estrogen, testosterone and vitamin D.^[5]

Bone, brain and prostate (mostly early or observational)

In animals, boron deficiency causes abnormal bone development and weaker bones. In humans, the bone data mainly come from women and do not show a direct effect on bone mineral density.^[1] Limited data suggest that very low boron intake may reduce mental alertness and executive function.^[1]

For prostate health, observational studies link higher boron intake with lower prostate cancer risk, and a Turkish study found smaller prostate glands in men with intakes around 6 mg a day compared with 0.64 to 0.88 mg a day, with no difference in PSA.^[1] There are no clinical trials, so these are associations, not proof that boron protects the prostate. Prostate symptoms or a rising PSA need a doctor, not a supplement.

How Boron May Work

Researchers have proposed a few mechanisms, none fully proven in men:

• Free versus bound hormones: the one-week study measured higher free testosterone and lower estradiol, which suggests boron may change how sex hormones are carried or broken down rather than how much the body makes. This idea has not been confirmed in larger studies.^[3]
• Inflammation: boron appears to lower inflammatory markers, and inflammation can affect hormone signaling. Examine suggests this may be the real driver of any hormonal change.^[2]
• Mineral and vitamin D handling: in controlled feeding studies, very low boron intake lowered plasma calcium and serum 25-hydroxyvitamin D.^[1] Low vitamin D is common in men, which is one reason boron gets linked to it. See our guide to vitamin D for men.

How Much Boron Should a Man Take?

There is no official dose because boron has no RDA. Here is what the research actually used:

• 3 mg a day is the lowest dose Examine lists as active, and a 2015 review notes that no studies to date showed benefits above 3 mg a day.^[2][5]
• 6 mg a day was used in most joint and osteoarthritis studies.^[1][2]
• 10 mg a day was used in the one-week free testosterone study.^[3]
• 20 mg a day is the adult upper limit from all sources combined. For teens aged 14 to 18 the limit is 17 mg.^[1]

Examine notes that the optimal dose is unknown and that, since human safety research is limited, smaller doses may be the wiser choice.^[2] A sensible approach is to start with food, and if you add a supplement, stay around 3 mg a day, take it with a meal, and count any boron already in your multivitamin.

Best food sources of boron

You can reach roughly 3 mg a day from food alone with a few servings of fruit, nuts and beans. Amounts below are from the NIH Office of Dietary Supplements.^[1]

Notice that meat, rice and bread contribute almost nothing. A day with an avocado, an apple, a pear and a handful of peanuts already lands near 2.7 mg. Many of the same foods appear in our list of foods men eat for hormone health.

Boron Side Effects and Safety

Boron from food and drinking water has no documented adverse effects, according to the NIH.^[1] Supplements at studied doses (1.5 to 10 mg) were generally well tolerated in short trials, though Examine points out that human research on side effects is limited.^[2]

The toxicity data come from accidental swallowing of boric acid or borax (household and pest control products). Symptoms include nausea, vomiting, diarrhea, stomach discomfort, skin flushing and rash, and in severe cases convulsions, kidney injury and vascular collapse. Most cases involve children under 6, and the fatal dose for adults is estimated at about 15,000 to 20,000 mg, far above any supplement.^[1] Never use boric acid or borax products as a “boron supplement.”

Interactions

The NIH lists no known clinically relevant interactions between boron and medications.^[1] That does not mean none exist; it means none have been documented.

Who Should Avoid Boron or Talk to a Doctor First

• Men with kidney disease: boron is cleared through urine, so reduced kidney function deserves a doctor’s input before supplementing.
• Men with hormone-sensitive conditions (such as prostate cancer) or on hormone therapy, since boron may shift sex hormone levels.
• Anyone already taking a multivitamin or “testosterone” formula: add up the boron from all products so you stay well under 20 mg a day.
• Men with symptoms such as low libido, fatigue or erection problems: these can signal heart, metabolic or hormonal issues. See a clinician and get blood work before trying supplements.
• Children and teens: their upper limits are much lower, and they should not take boron supplements without medical advice.

Where Ultra Bann Fits

Ultra Bann is a natural male vitality supplement by DL Bioproducts, taken as one capsule every 2 days. It contains seven botanicals with every amount on the label and no proprietary blend: Thai Butea superba 345 mg, Panax ginseng 110 mg, Cynomorium songaricum 85 mg, black ginger (Kaempferia parviflora) 85 mg, tongkat ali 85 mg, epimedium 45 mg and reishi 45 mg, for 800 mg total. Boron is not one of its ingredients, so if you choose to take boron, this capsule does not add to your daily boron total. You can review the full label on our ingredients page. First orders ship free in the US and include a 60-day money-back guarantee at the Ultra Bann shop.

Frequently Asked Questions

Does boron really increase testosterone in men?

Possibly a little, in the short term. One small study of 8 men taking 10 mg a day for a week saw higher free testosterone and lower estradiol, while a 7-week trial using 2.5 mg a day found no change versus placebo. There is no long-term evidence, so boron should not be treated as a testosterone therapy.

How much boron should a man take per day?

There is no official recommendation. Most studies used 3 to 6 mg a day, the testosterone study used 10 mg, and the adult upper limit is 20 mg a day from all sources. Around 3 mg a day, from food or a supplement taken with a meal, is a conservative choice.

How long does boron take to work?

In the studies, changes in inflammatory markers and free testosterone were measured after one to two weeks, and joint comfort studies ran two to eight weeks. Whether those changes translate into noticeable effects is not established.

Is it safe to take boron every day?

For healthy adults, daily intake well below 20 mg appears safe, and dietary boron has no reported adverse effects. Long-term studies of supplements are lacking, so keep doses modest and check with your doctor if you have kidney problems or a hormone-sensitive condition.

References

1. NIH Office of Dietary Supplements. Boron: Fact Sheet for Health Professionals. ods.od.nih.gov
2. Examine.com. Boron. examine.com
3. Comparative effects of daily and weekly boron supplementation on plasma steroid hormones and proinflammatory cytokines. Physiology and Pharmacology. 2012;15(3):403. magiran.com
4. Green NR, Ferrando AA. Plasma boron and the effects of boron supplementation in males. Environmental Health Perspectives. 1994;102 Suppl 7:73-7. PMID 7889885. pubmed.ncbi.nlm.nih.gov
5. Pizzorno L. Nothing Boring About Boron. Integrative Medicine (Encinitas). 2015;14(4):35-48. PMID 26770156. pubmed.ncbi.nlm.nih.gov

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease. This article is for information only and is not medical advice.