Shilajit

The short answer

Shilajit is a mineral-rich resin that seeps from mountain rock. In 63 active men, 500 mg a day for eight weeks helped the stronger half of the group hold on to strength after a tiring workout; 250 mg did nothing. A 90-day trial in men aged 45 to 55 found testosterone readings rose against placebo.

The form, and why it matters

Shilajit is sold as raw resin, purified resin and extracts. Mast uses 400 mg of a 30:1 extract, meaning thirty parts of raw material were concentrated to one. The trials used a branded purified shilajit, which is a different preparation.

Typical dose

Both trials found their results at 500 mg a day of purified shilajit, as 250 mg twice daily or 500 mg once. Mast carries 400 mg of 30:1 extract in one capsule a day.

What the research shows

In 63 recreationally active men over eight weeks, the 500 mg group's strength fell 8.9% after a fatiguing protocol against 16.0% on placebo, but only among men who started in the stronger half; 250 mg showed no effect. In a 90-day randomised, double-blind trial of healthy men aged 45 to 55, total testosterone, free testosterone and DHEAS rose compared with placebo.

Who should be careful

Do not take shilajit if you are pregnant or nursing. Talk to your clinician first if you have a hormone-sensitive condition or take prescription medicine. Buy it only from a source that tests each batch, since raw shilajit can carry heavy metals.

Where it sits in our formulas

Sources

• Keller et al., The effects of shilajit supplementation on fatigue-induced decreases in muscular strength and serum hydroxyproline levels, J Int Soc Sports Nutr
• Pandit et al., Clinical evaluation of purified shilajit on testosterone levels in healthy volunteers, Andrologia

Figures checked against the sources above on 21 September 2026.