Boron and Testosterone: The Hidden Gem Mineral Most Men Overlook
When men think about minerals for testosterone, zinc and magnesium dominate the conversation. Boron rarely gets mentioned, though it has shown up in a small amount of preliminary research on sex hormones. The honest summary is that the evidence in men is very thin. This article covers what that research found, what it cannot tell us, and the safety issues to keep in mind.
This article is educational and is not medical advice. Supplements are not intended to diagnose, treat or prevent any condition. Talk to a doctor before starting any supplement.
Key takeaways
- The main study had 8 healthy men take 10 mg of boron daily with breakfast for one week; mean plasma free testosterone rose significantly and estradiol fell, but DHT, cortisol and vitamin D also rose.[1]
- Effects in a study this small, with no separate placebo group for the week, do not show that boron raises testosterone in everyday use. A 2026 critical review concluded current human data are insufficient to justify supplementation.[2]
- No official requirement exists for boron. Adults typically consume about 1 to 1.5 mg a day, and the upper intake level is 20 mg a day (based on animal reproductive and developmental effects).[3]
What the Research Actually Shows
The most frequently cited study on boron and testosterone was published in 2011 in the Journal of Trace Elements in Medicine and Biology. Eight healthy male volunteers attended the lab on three occasions. On day 0 they took a placebo with breakfast, on day 1 a 10 mg boron capsule, and then a 10 mg boron capsule every day through day 7. Six hours after the first dose, SHBG, hs-CRP and TNF-alpha were significantly lower. After one week (blood drawn at 8 a.m. only), mean plasma free testosterone had increased and mean plasma estradiol had decreased significantly, and dihydrotestosterone, cortisol and vitamin D had gone up.[1]
These are important limits. There were only eight participants, the comparison was against each man's own placebo day rather than a parallel placebo group, and the study lasted a week. The author described it as the first human study to report an increase in free testosterone after boron consumption.[1] We did not find larger randomized trials in men that replicate it. A 2026 critical review of boron research concluded that human evidence is limited to studies of modest sample size and that current data are insufficient to justify dietary recommendations or supplementation.[2]
Free Testosterone and SHBG
Much of the testosterone in blood is bound to proteins such as sex hormone-binding globulin (SHBG) and albumin. According to the free hormone hypothesis, only the unbound fraction is biologically active in target tissues, although this hypothesis has been debated and the binding models behind free testosterone calculations have been questioned.[4] A drop in SHBG was seen in the boron study, and that is the usual explanation offered for a rise in free testosterone, but this is a hypothesis, not a demonstrated mechanism. See our explainer on free vs total testosterone for more.
Food Sources vs. Supplements
The Institute of Medicine reports that the highest boron concentrations are in fruit-based beverages, tubers and legumes. Foods rich in boron include avocado, peanut butter, peanuts, prune and grape juice, wine and raisin cereals, while coffee, milk, apples, dried beans and potatoes are the major contributors to intake once serving frequency is accounted for. Adults typically consume about 1 to 1.5 mg of boron a day from diet and supplements combined.[3]
No Estimated Average Requirement, Recommended Dietary Allowance or Adequate Intake has been set for boron, because evidence for a clear biological function in humans was considered insufficient.[3] A diet with plenty of fruit, vegetables, legumes and nuts naturally provides more boron, and that is a sensible place to start. For other nutrient options, see our guides to vitamin D and zinc and magnesium.
Dose Used in Studies and Safety
The study discussed above used 10 mg of boron daily for a week.[1] That is a study dose in a short experiment, not a recommendation, and no effective or optimal dose for testosterone has been established. A narrative review of boron noted that, in the studies it covered, reported benefits did not appear at intakes above 3 mg a day, and that the upper intake level for adults is 20 mg a day.[5]
✓ Sensible Approach
- •Getting boron from fruit, vegetables, nuts and legumes
- •Asking a doctor before taking any supplement
- •Staying well below the 20 mg/day upper intake level
- •Treating results from one 8-man study as preliminary
✗ Risky Approach
- •Taking high-dose boron because of a single small study
- •Combining several mineral supplements without advice
- •Using supplements instead of getting low symptoms checked
- •Assuming it is risk-free because it is a trace mineral
The 20 mg/day upper intake level is based on reproductive and developmental effects (reduced fetal weight and skeletal malformations) seen in animal studies at higher doses.[3] Long-term human safety of boron supplements at the doses discussed online has not been studied well, and the main hormone study lasted only a week.
Talk to a Doctor First
Check with a doctor or pharmacist before taking a boron supplement, especially if you take prescription medication, have a kidney, hormone-related or reproductive condition, are trying to conceive, or are taking other supplements. If you have symptoms such as persistent fatigue, low libido or mood changes, get evaluated and consider a morning blood test rather than self-treating, since many treatable causes exist.
The Bottom Line
Boron is an interesting but unproven idea for testosterone. The only human data we found came from a single very small study, and larger trials are needed. For men who want to support their hormones, the strongest-evidence levers remain sleep, resistance training, a healthy body weight, and stress management. For a wider look at supplement evidence, see testosterone supplements: what actually works and our daily habits guide.
Related Reading
- How to Increase Testosterone Naturally: where supplements sit in the hierarchy of interventions.
- The Complete T-Maxing Guide: the full habit stack any supplement should layer on top of.
How Thrive Helps
Thrive helps you track the habits that research connects to hormonal health: sleep, training consistency, stress management and nutrition. Try Thrive free. Thrive is a wellness app, not a medical device, and does not diagnose or treat any condition.
References
- Naghii MR, Mofid M, Asgari AR, Hedayati M, Daneshpour MS. Comparative effects of daily and weekly boron supplementation on plasma steroid hormones and proinflammatory cytokines. Journal of Trace Elements in Medicine and Biology. 2011. doi.org/10.1016/j.jtemb.2010.10.001
- Melenikioti E, Pavlidou E, Dakanalis A, Giaginis C, Papadopoulou SK. Dietary lithium, silicon, and boron: an updated critical review of their roles in metabolic regulation, neurobiology, bone health, and the gut microbiome. Nutrients. 2026. doi.org/10.3390/nu18030386
- Institute of Medicine (US) Panel on Micronutrients. Dietary Reference Intakes for vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc. National Academies Press. 2001. doi.org/10.17226/10026
- Goldman AL, Bhasin S, Wu FCW, Krishna M, Matsumoto AM, Jasuja R. A reappraisal of testosterone's binding in circulation: physiological and clinical implications. Endocrine Reviews. 2017. doi.org/10.1210/er.2017-00025
- Pizzorno L. Nothing boring about boron. Integrative Medicine (Encinitas). 2015. pubmed.ncbi.nlm.nih.gov/26770156/