Shilajit is a blackish-brown exudate that seeps from rock in the Himalaya and other mountain ranges, formed over long periods from decomposed plant matter. It is made of humic substances, mainly fulvic acids, together with dibenzo-alpha-pyrones and a long list of minerals. In Ayurvedic medicine it is a rasayana, a rejuvenator, and in Russian and Central Asian folk medicine the same material is mumie or moomiyo.

It is sold to men for testosterone, strength and energy, which is why it sits in this section. The human trial literature is small and recent, and nearly all of it tests a purified, standardized extract, several trials the same branded one. That matters twice over: the results may not transfer to the raw resin sold in jars, and the raw resin carries a heavy-metal problem the purified extract was designed to remove.

The constituents the literature credits are fulvic acid and dibenzo-alpha-pyrones, which are proposed to support mitochondrial ATP production, carry electrons in the respiratory chain, and act as antioxidants. A 2014 review collects animal and in vitro work for antioxidant, anti-inflammatory, adaptogenic and immunomodulatory effects, and for enhanced spermatogenesis in animals. In humans, a 2019 placebo-controlled transcriptome study found 14 weeks of the extract turned on genes involved in blood vessel growth and extracellular matrix in skin and improved skin microperfusion, and the same group had earlier reported extracellular matrix genes induced in muscle. These are leads, not an established mechanism, and the dose that produces them in people is not known.

Testosterone. The trial that sells the product: healthy men aged 45 to 55 took 250 mg of purified shilajit twice a day or placebo for 90 days in a randomized, double-blind trial. Total testosterone, free testosterone and DHEAS rose significantly compared with placebo, with LH and FSH unchanged. The abstract gives no numbers and no sample size. A 2024 systematic review of 52 trials of 27 proposed testosterone boosters found most fail to raise total testosterone, and listed purified shilajit among the few it rated possibly effective, and only for men with late-onset hypogonadism.

Strength and fatigue. In the strength trial, 63 recreationally active young men took 250 mg per day, 500 mg per day or placebo for 8 weeks. In the stronger half of the sample, the 500 mg group lost less maximal strength after a fatiguing protocol (8.9% decline against 16% on placebo and 17% on the low dose) and had lower serum hydroxyproline, a marker of collagen breakdown. The low dose did nothing measurable, and the headline result comes from a subgroup.

Bone. In a 48-week trial, 60 postmenopausal women with osteopenia took 250 mg, 500 mg or placebo daily. Bone density at spine and hip fell on placebo and the fall was attenuated, dose-dependently, on the extract, with bone turnover, oxidative stress and CRP markers moving the same way. Not a men's health trial, but the longest and best-run one in the file.

Open-label. A 2026 pilot gave 25 healthy men 500 mg per day of a resin product for 28 days with no control group and reported strength, endurance and fatigue improvements. Without a placebo arm those numbers are not evidence of anything.

The whole clinical file is a handful of trials, each of 25 to 63 people, each funded or supplied by a manufacturer, and none replicated independently.

In the trials, no adverse effects were reported over periods up to 48 weeks, and the 2014 review calls safety well documented in animal and human studies. The problem is not the trial product but the market.

Shilajit is a mineral exudate and carries whatever metals the rock carried. A 2022 analysis of the Indian and Pakistani shilajit most widely sold found aluminum, strontium, manganese, barium, zinc, nickel, boron, chromium, lead, arsenic and mercury in amounts exceeding permissible limits. A 2024 review counted around 65 metals reported in shilajit, including lead, arsenic, cadmium and mercury, and concluded that consumption without knowing the metal content is not safe. Purified, standardized extracts exist precisely because of this; a raw resin bought online may or may not have been tested, and the label will not tell you.

It is also sold as a testosterone product, so the usual cautions apply: anyone with prostate disease, or on hormone treatment, should not add it without a clinician knowing.

A traditional Ayurvedic preparation in India and a dietary supplement in the United States, the United Kingdom and the European Union, sold without review of its claims. No regulator has approved it for testosterone, strength or anything else. Heavy-metal limits for herbal products exist in most jurisdictions, and the published analyses suggest some products on sale exceed them.