Shilajit: What the Small Trials Actually Found

The Oasis Health Journal · Submitted July 24, 2026 · 11:16 AM ET

Shilajit is tar. It seeps out of rocks in the Himalayas and a few other mountain ranges, gets scraped off, and gets purified into a dark, sticky resin. People have taken it for a very long time. The research is younger and smaller than the tradition, so this is a short tour of what the human trials measured, and what they did not.

What it actually is

Shilajit is a mineral resin. Its two headline ingredients are fulvic acid and a group of compounds called dibenzo-alpha-pyrones. A 2014 review in Phytotherapy Research summed up the state of things plainly: the safety record in animal and human studies is well documented, the resin shows antioxidant and adaptogenic activity in the lab, and there are still relatively few well-controlled human studies. The author asked for more of them. That is a fair place to start.

One practical note. Raw shilajit scraped straight off a rock is not the same as the material used in studies. The trials used purified or processed shilajit for a reason. Unpurified resin can carry heavy metals and other contaminants, so the form matters. The version the research is talking about is a purified shilajit, not a lump off the mountain.

Testosterone, in older men

The most cited human trial is a 2016 study in Andrologia. It was randomised, double-blind, and placebo-controlled, which is the setup you want. The participants were healthy men aged 45 to 55. They took 250 mg of purified shilajit twice a day for 90 days. At the end, the shilajit group had higher total testosterone, free testosterone, and DHEAS than the placebo group, and the difference was statistically significant. Two other hormones, LH and FSH, stayed level.

The caveats are worth saying out loud. This was one trial, in men already in their late forties and fifties, over three months. Taking it was associated with higher hormone readings on paper. That is not a promise about how anyone feels, and it is not the same thing as a prescription. It is one data point, and a reasonably clean one.

Muscle strength after fatigue

A 2019 trial in the Journal of the International Society of Sports Nutrition took a different angle. Sixty-three recreationally active men, average age about 21, were split into placebo, 250 mg a day, and 500 mg a day of a branded shilajit for eight weeks. Then they wore their legs out with repeated maximal leg extensions, and the researchers measured how much strength they lost.

In the stronger half of the group, the 500 mg dose held onto more strength after the fatiguing protocol. Their strength dropped by about 9 percent, versus about 16 percent on placebo. The 250 mg dose did nothing better than placebo. So the effect showed up only at the higher dose, only in the subgroup that started out stronger, using one company's product. If you already train, shilajit sits in the same conversation as workhorses like creatine, with a great deal less evidence behind it.

Sperm parameters

A 2010 study in Andrologia looked at men with low sperm counts. Thirty-five men enrolled, took 100 mg of processed shilajit twice a day for 90 days, and 28 finished. Among those who finished, total sperm count rose by about 61 percent, motility improved, the share of normally shaped sperm went up by about 19 percent, and a marker of oxidative stress in semen dropped. Serum testosterone rose by about 23 percent.

Those are large-looking numbers, so here is the asterisk. There was no placebo group. Everyone got shilajit, so there was nothing to compare against, and only the men who completed the course were counted. That is a promising signal, not a verdict. Read it as a reason for a bigger study, not as a result you can bank on.

Energy, and the ATP story

Shilajit gets sold as an energy supplement, and the mechanism people point to is ATP, the molecule your cells spend to do work. The 2014 review noted human and animal data supporting shilajit's traditional use as a revitalizer, with better ATP production floated as the reason physical performance and fatigue might respond. That is a plausible story with real but early support. If cellular energy is your interest, it overlaps with the territory of CoQ10, which has a much larger body of work behind it. Shilajit is the newer, smaller entry.

The honest summary

Three small human trials, one review, and a long folk history. The testosterone trial is the cleanest. The strength trial worked only at the high dose, and only in part of the group. The sperm study had no control group. None of them are large. Shilajit is associated with some interesting readings, the safety record looks reasonable for purified forms, and the field needs bigger trials before anyone talks in certainties. That is roughly where the science stands, minus the marketing.

This article is for education, not medical advice. Talk with your clinician before starting a new supplement, especially if you are pregnant, nursing, or taking medication.

Sources

1. Pandit S, Biswas S, Jana U, De RK, Mukhopadhyay SC, Biswas TK. Clinical evaluation of purified Shilajit on testosterone levels in healthy volunteers. Andrologia, 2016;48(5):570-575. PubMed
2. Keller JL, Housh TJ, Hill EC, Smith CM, Schmidt RJ, Johnson GO. The effects of Shilajit supplementation on fatigue-induced decreases in muscular strength and serum hydroxyproline levels. Journal of the International Society of Sports Nutrition, 2019;16(1):3. PubMed
3. Biswas TK, Pandit S, Mondal S, Biswas SK, Jana U, Ghosh T, Tripathi PC, Debnath PK, Auddy RG, Auddy B. Clinical evaluation of spermatogenic activity of processed Shilajit in oligospermia. Andrologia, 2010;42(1):48-56. PubMed
4. Stohs SJ. Safety and efficacy of shilajit (mumie, moomiyo). Phytotherapy Research, 2014;28(4):475-479. PubMed