Not directly. But low magnesium will suppress it, and correcting that deficiency will bring it back up. That distinction matters.
Magnesium is involved in testosterone synthesis. Studies consistently show a correlation between magnesium levels and testosterone levels, particularly in men who train. One trial in athletes found that supplementing magnesium for four weeks produced a significant increase in both free and total testosterone compared to placebo.
The mechanism
There are two main pathways. The first is direct. Magnesium is required for the enzymatic processes that produce testosterone. When it's deficient, those processes are impaired.
The second is indirect, and probably more significant. Magnesium improves sleep quality. Better sleep means higher growth hormone and testosterone production overnight, which is when most of it happens. Magnesium also reduces cortisol, which competes directly with testosterone. Lower cortisol, higher testosterone. Simple relationship.
What this means in practice
If your magnesium levels are already optimal, supplementing more won't push your testosterone higher. The effect is about correcting a deficiency, not stacking an advantage.
But if you're deficient, which a large proportion of men are, getting your magnesium right is one of the most straightforward things you can do for your hormonal health. It's not flashy. It's foundational.
For any man serious about maintaining testosterone as he gets older, magnesium belongs in the stack alongside vitamin D3. Both are fundamental. Both are commonly low. Both directly affect the hormonal environment you're operating in.
Related reading: Does magnesium actually help with sleep?, Why are most men deficient in magnesium and don't know it?