Does boron raise testosterone?

Possibly — small studies suggest boron can nudge free testosterone up and lower SHBG, but the evidence is thin and the effect is best seen as minor.

Boron is a trace mineral, and a few short human studies have found interesting effects: supplementing around 6–10 mg a day for a week or so raised free testosterone, lowered SHBG (freeing up more usable testosterone), reduced oestrogen, and dampened inflammation in some participants. That's a promising profile on paper. But the studies are small, short, and few, so boron sits firmly in the early-and-unproven category rather than the reliable one.

It's also worth keeping perspective. Even where boron helped, the changes were modest, and most men aren't boron-deficient. As with most minerals, the real benefit (if any) comes from correcting a shortfall — and a normal diet with fruit, nuts, and vegetables already provides some.

What to do: boron is cheap and generally safe at low doses (around 3–6 mg a day; don't exceed roughly 20 mg), so it's a low-risk experiment if you're curious — but keep expectations modest and don't treat it as a fix. The bigger levers (sleep, body fat, training, fixing a vitamin D or zinc deficiency) will always do more.