Does shilajit actually work as a supplement?

Shilajit has shown some measurable effects in men in small studies. One double-blind study in men aged 45 to 55 found a significant rise in testosterone after 90 days of use at 500 mg per day, compared with placebo. This comes from a single small study by a single research group, so it is an early signal, not an established fact.

The picture for athletic performance is mixed. In 63 recreationally active men, 500 mg per day reduced muscle strength loss after fatigue, but only in men who were already reasonably strong. At a lower dose (250 mg) there was no difference compared with placebo. Another small study (35 men) found that shilajit raised a blood marker for collagen production. Whether that actually translates into stronger tendons or better recovery has not yet been demonstrated.

In people with risk factors for a metabolic disorder, shilajit was tested in combination with chromium and a plant extract. There were indications of improvement in areas including blood lipids and insulin sensitivity, but the effects were inconsistent. Moreover, it is impossible to say what shilajit itself contributed, because it was never tested on its own. This research was partly funded by a commercial company (Kerry Inc.), which complicates the interpretation.

An important practical point: shilajit is not a uniform substance. Laboratory research shows that its composition varies considerably depending on the region of origin, sometimes with opposing effects on gut bacteria. What you buy in a supplement can therefore differ substantially from what was used in studies. Combined with the small number of well-designed human studies, this means that the efficacy and safety of shilajit as a supplement remain uncertain for the time being.