Boron glycinate

Tier 3 — weak evidence · Boron form · Bone · Hormonal

Boron chelated to glycine for better tolerance than borax or boric acid. Boron at 3-10 mg/day has small but consistent effects on calcium/magnesium retention, free testosterone (modest rise), and inflammatory markers. It is a conditionally essential trace element with no formal RDA but intakes below 0.5 mg/day correlate with poorer bone and hormonal outcomes. Toxicity is not a concern at supplemental doses (UL is 20 mg/day for adults) but high-dose boric acid is reproductively toxic.

Dose: 3–10 mg elemental boron daily