Naghii · Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS) 2011 · non-randomized before-after trial · n=8

Comparative effects of daily and weekly boron supplementation on plasma steroid hormones and proinflammatory cytokines.

Cited 121 times in the scientific literature.

Level 4 - case-series / case-control

Small non-randomized before-and-after trial with sequential placebo and intervention phases

PubMed 21129941 · doi:10.1016/j.jtemb.2010.10.001 · record verified 2026-08-29

What was done

Eight healthy male volunteers were evaluated across three laboratory visits (days 0, 1, and 7). On day 0, baseline blood was drawn at 8:00 AM followed by a placebo with breakfast and serial blood collections every 2 hours for 6 hours. On day 1, subjects repeated the protocol with an acute dose of 10 mg boron. Participants then consumed 10 mg of boron daily with breakfast for one week, with a final fasting blood draw at 8:00 AM on day 7. Plasma boron, steroid hormones (free testosterone, estradiol, dihydrotestosterone, SHBG, cortisol), vitamin D, and inflammatory biomarkers (including hsCRP and TNF-α) were evaluated.

What was found

Plasma boron increased significantly after acute and weekly intake. At 6 hours post-dose, SHBG, hsCRP, and TNF-α decreased significantly. After one week of daily supplementation, mean plasma free testosterone increased significantly, mean plasma estradiol decreased significantly, and dihydrotestosterone, cortisol, and vitamin D were elevated. All three measured inflammatory biomarkers decreased. The abstract reports directional changes and significance claims but provides no exact numbers, baseline values, effect sizes, or p-values.

Why it matters

This study provides early preliminary human data suggesting that short-term oral boron supplementation may acutely modulate sex hormone binding and steroid metabolism while reducing systemic inflammatory markers.

Limits

The sample size is extremely small (n = 8) and restricted entirely to healthy males. The study used a non-randomized sequential design without a parallel control group or blinded crossover. The abstract reports no numerical values, variances, or exact significance thresholds. Duration was limited to 7 days, leaving long-term efficacy and safety unassessed.

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