Shilajit (Purified)

What Shilajit Actually Is

Shilajit is not a plant and not a mineral. It is a blackish-brown exudate that seeps from rock in the Himalaya, Altai, Caucasus and other high ranges — the product of centuries of microbial and geological processing of plant matter. Chemically it is a humic substance: mostly fulvic acid, humic acid, and a family of dibenzo-alpha-pyrones (DBPs) bound to proteins and minerals, with dozens of trace elements along for the ride.

That last phrase is the whole safety story. The same fulvic acid that makes shilajit an efficient mineral carrier makes raw shilajit an efficient carrier of whatever the rock contained. A 2024 review in Biological Trace Element Research catalogued around 65 metals in shilajit samples, including lead, arsenic, cadmium and mercury. Most reported levels sat below WHO and FDA limits for herbal products — but not all, and the authors state plainly that consuming shilajit without knowing its metal content is not safe.

Everything below therefore refers to purified, standardised shilajit with a batch certificate of analysis. Raw resin, "wild-harvested" tar and unlabelled powders are a different substance with a different risk profile, and nothing in the clinical literature applies to them.

The Two Human Trials

Shilajit's reputation runs far ahead of its evidence. The evidence is two small trials, both 90 days, both from the same institution — J. B. Roy State Ayurvedic Medical College in Kolkata — and both using a processed product from a single manufacturer. A 2024 systematic review of "testosterone boosters" rated purified shilajit as possibly effective for men with late-onset hypogonadism, which is roughly the right weight to put on it.

The testosterone trial (2016). Healthy men aged 45–55 were randomised to purified shilajit 250 mg twice daily or placebo for 90 days. The abstract reports significantly higher total testosterone, free testosterone and DHEAS versus placebo (P < 0.05) with LH and FSH "well maintained." Two things it does not report: the effect sizes, and the sample size. A positive result at P < 0.05 with no magnitude stated is a signal, not a number you can plan around.

The oligospermia trial (2010). Sixty infertile men were screened; 35 with sperm counts below 20 million/mL were enrolled on processed shilajit 100 mg twice daily after meals, and 28 completed. Against baseline, total sperm count rose 61.4%, motility 12.4–17.4% depending on the time interval assessed, and normal sperm forms 18.9% (all P < 0.001). Serum testosterone rose 23.5% and FSH 9.4%. Semen malondialdehyde — an oxidative stress marker — fell 18.7%. Liver and kidney panels were unchanged.

Those are the strongest shilajit numbers in the literature, and the design has to be stated alongside them: there was no placebo group. Twenty-eight men were compared to their own baseline. Sperm parameters vary substantially between samples from the same man, and regression to the mean in a group selected for low counts is guaranteed to flatter any before-after comparison. The result is a credible reason to run a controlled trial — which, fifteen years later, nobody has.

What Shilajit Has Never Shown

• A pregnancy or live birth. No shilajit trial has measured the outcome that a man taking it for fertility actually wants.
• A replicated result. Both trials share an institution and a product. No independent group has confirmed either.
• An effect size for testosterone. The placebo-controlled trial reports significance without magnitude.
• Anything in men under 45 with normal testosterone. The androgen trial enrolled men 45–55; the fertility trial enrolled men already oligospermic.
• Anything beyond 90 days. Long-term safety of continuous use is unstudied in humans.
• Energy or "vitality" in a human RCT. The revitaliser claims rest on animal ATP data and a narrative review.

On the testosterone route specifically, shilajit is a weaker bet than Tongkat Ali, which has several independent human RCTs. It is reviewed against that comparator in Natural Testosterone Optimization: What Actually Works, and the reason it belongs in a fertility protocol rather than a testosterone stack is set out there.

Dosing and Product Selection

Two rules follow from the chemistry:

1. Purified and tested, or nothing. Look for a stated fulvic acid or DBP standardisation and a third-party certificate of analysis listing lead, arsenic, cadmium and mercury for the batch. Ask whether the batch was screened for mycotoxins as well — an unprocessed organic exudate is a plausible substrate for fungal contamination, and a reputable manufacturer will have the answer. "Himalayan" and "authentic" on a label are marketing terms, not analytical ones.

2. Ninety days is the unit. Spermatogenesis takes roughly two and a half months from stem cell to ejaculated sperm. The fertility trial ran 90 days for that reason, and judging a semen analysis any sooner measures the previous cycle, not the intervention.

There is no evidence that doses above 500 mg/day do anything more, and the mineral load rises with the dose.

Who This Is Reasonable For

Shilajit is a grade C compound with a specific, narrow use case: a man with a documented low sperm count or motility, whose urologist has excluded a correctable cause, who wants to add a mechanism-plausible supplement to a three-month cycle that already includes the better-evidenced CoQ10 — and who is buying a purified, batch-tested product.

It is not reasonable as a testosterone intervention in a man with normal levels, as a substitute for evaluation of infertility (varicocele, obstruction and hormonal causes need a clinician before any supplement), in anyone with iron overload, in pregnancy, or in any form that has not been analysed for heavy metals.

Where it sits in a full fertility and sexual-function sequence — including what comes before it and how to judge it — is set out in The Male Vitality Protocol.

Related Research

• The Male Vitality Protocol: Fertility and Sexual Function Beyond Testosterone
• The Male Vitality Protocol
• Natural Testosterone Optimization: What Actually Works (and What Doesn't)
• Coenzyme Q10