Shilajit

In the summer, on certain rock faces in the Himalaya, a dark resin seeps out of cracks in the strata. It softens in the heat, runs slowly, and hardens again as the temperature drops. Local collectors have gathered it for centuries, working the high passes in the short window when it appears.

That substance is shilajit. It is not a plant, and this is the first thing worth saying about it, because almost everything sold in the wellness aisle is. Shilajit has no Latin binomial and no botanical family. It has a geology instead.

What it is

Shilajit is a humic substance — an exudate formed within rock strata over a very long period, from compressed plant material altered by pressure, temperature and microbial activity. The precise mechanism is still debated in the literature, and anyone who tells you otherwise is more confident than the evidence allows.

What it contains is better established: fulvic acid and humic acid as the principal fractions, alongside dibenzo-α-pyrones and a spread of trace minerals absorbed from the surrounding rock. Fulvic acid is the marker compound most commonly used to grade it commercially.

It appears under different names across its range. Shilajit is Sanskrit — from śilā, rock, and jatu, exudate. Rock-exudate, more or less literally. You will often see it translated as “conqueror of mountains” or “destroyer of weakness”; these are marketing glosses rather than translations. In Russian and Central Asian sources the same or similar material appears as mumijo, in Urdu as salajeet.

Raw shilajit is not consumable. It comes off the rock mixed with mineral debris, plant fragments and whatever else the strata contained — which is why every tradition that uses it also specifies how to purify it first. That process matters more than the sourcing, and it’s covered further down.

What the tradition says

Shilajatu appears in the classical Ayurvedic compendia, where it is grouped among the rasayana — a category of preparations associated with longevity, vigour and the restoration of the body over time. Rasayana is not a pharmacological classification and doesn’t map onto a modern one; it describes a role within a system of thought that also encompasses diet, routine, sleep and the seasons.

The Charaka Samhita is notably extravagant about it. The text asserts there is no curable condition that shilajatu cannot address.

We report that because it’s in the text, and because it tells you something real about the standing the substance held. We are not endorsing it. A first-millennium compendium making a sweeping claim is a historical fact; it is not evidence, and the gap between those two things is the whole reason this library exists.

What the classical sources are more useful on is process. They are specific about purification, insistent that unpurified material shouldn’t be taken, and detailed about the seasons and conditions for collection. On the practical questions, the tradition has held up considerably better than on the therapeutic ones.

What the research shows

Honestly: not much, and less than the marketing around it suggests.

The published human research on shilajit consists largely of small trials — typically a few dozen participants, run over weeks rather than years. Several come from a narrow group of research centres. A number are funded by manufacturers. Some report findings on measures including fatigue, altitude tolerance and hormonal markers in men.

What’s missing is the part that matters: large, independent, replicated trials. Without those, individual positive findings are a reason to keep looking, not a basis for telling you what this will do.

There is also a specific problem with the evidence base that gets very little attention. Because fulvic acid content varies enormously between commercial products — analyses have found differences of several orders of magnitude across products sold under the same name — a trial of one preparation tells you comparatively little about another. Two capsules labelled “shilajit” may have very little in common. That is a real limitation on generalising any of this research, including the favourable studies.

Evidence: limited. Small human trials, several industry-funded, little independent replication. Product variability further limits what can be generalised.

⟨TO VERIFY BEFORE PUBLISHING: pull the three or four most-cited human trials, check sample sizes, funding declarations and preparation used, and cite them individually in the references below. Do not publish this section with general statements alone — the specificity is the point.⟩

Safety and suitability

This is the section that matters most, and the one most shilajit pages don’t have.

Contamination is a genuine and documented problem. Because shilajit forms in rock, it takes up whatever the rock contains. Commercial products have been found carrying lead, arsenic, mercury and cadmium; a 2025 analysis detected elevated thallium across several processed supplements. Purification reduces this. It does not reliably eliminate it, and purification quality varies enormously between producers.

This is not a reason to avoid shilajit. It is the reason to only ever buy it with a batch certificate from an accredited laboratory, and to check that the certificate covers heavy metals specifically. Our own testing regime is set out on the Sourcing and Testing page, with certificates published per batch.

Never take raw or unpurified shilajit. Material sold as “raw,” “wild-collected” or “straight from the mountain” as a selling point is describing an unfinished product. The tradition is unambiguous about this and so is the contamination data.

Not suitable during pregnancy or breastfeeding. There is insufficient safety data, which is a reason to avoid rather than a reason to assume it’s fine.

Speak to your GP or pharmacist first if you have haemochromatosis, thalassaemia, sickle cell disease or any other condition affecting iron handling; have gout or raised uric acid; take prescription medication of any kind.

Stop and seek advice if you experience any unexpected reaction.

Nothing on this page is medical advice, and it isn’t a substitute for speaking to a qualified professional about your own circumstances.

How it’s prepared

The traditional process is called shodhana — purification.

Raw material is broken up and soaked, usually in water or a herbal decoction. The soluble fraction is separated from rock debris and insoluble matter by filtration, often repeatedly. The filtrate is then reduced, traditionally by sun-drying, into a resin or dried into a powder.

The point of this is straightforward: separate what’s wanted from what came off the mountain with it. Repetition matters, and so does the medium used for soaking — different classical texts specify different decoctions.

Modern manufacture varies. Some producers follow essentially the traditional process at scale; others use solvent extraction and spray-drying, which is faster and produces a more consistent standardised powder but a materially different product from what the classical texts describe. Neither is wrong. But they are not the same thing, and a page that blurs them is being careless.

How ours is made: [SUPPLIER: purification method, medium used, number of cycles, duration, drying method. Also whether resin or standardised extract, and if extract, the solvent.]

Where ours comes from

[SUPPLIER: collection region and altitude. Whether wild-collected or purchased through intermediaries. Season of collection. Name of processing facility and its certification status.]

Every batch is tested by an accredited laboratory for heavy metals, including thallium, microbial contamination and fulvic acid content. Certificates are published in full and linked from the specimen label above — not summarised, not “available on request.”

We publish the analytical method used for fulvic acid alongside the figure. Different methods return substantially different numbers for the same material, so a percentage without a method attached doesn’t mean very much.

References

⟨TO COMPLETE: classical citation for the Charaka Samhita passage, with chapter and verse and a note on which translation. Three to four human trials with full citation. The 2025 thallium analysis. A review paper on fulvic acid variability in commercial products.⟩