Ayurveda's 'conqueror of mountains' — a geological exudate with notable testosterone data in healthy men and strong fertility results. Small evidence base, but what exists is promising. Heavy metal contamination makes sourcing the whole game.
Traditions: Ayurveda, Unani
Multiple traditions agree on use.
Classified as Rasayanottama — 'supreme among rejuvenatives.' The Charaka Samhita declares: 'There is no curable disease in the universe which is not effectively cured by Shilajatu when administered at the appropriate time.' Name means 'conqueror of mountains and destroyer of weakness.' Used for vitality, sexual function, cognitive clarity, physical strength, longevity.
Recognized as a tonic, anti-inflammatory, and aphrodisiac. Used in combination formulations for general debility and weakness.
Two key clinical trials show +20% total testosterone and +19% free testosterone in healthy men (Pandit 2016, n=75), and +61% sperm count with +23.5% testosterone in infertile men (Biswas 2010, n=60). A third trial showed preserved muscle strength post-fatigue at 500mg/day. Promising effect sizes, but small evidence base — both T/fertility studies from overlapping research groups. More replication needed.
500mg/day PrimaVie for 90 days: total testosterone +20.45%, free testosterone +19.14%, DHEA +31.35% (all p<0.05) in healthy men aged 45-55. LH and FSH well-maintained.
200mg/day for 90 days: sperm count +61.4% (p<0.001), motility +12-17%, morphology +18.9%, testosterone +23.5%, oxidative stress marker MDA -18.7% in 60 infertile men.
500mg/day PrimaVie maintained maximal voluntary isometric contraction strength after fatiguing protocol (p=0.024) and reduced collagen degradation marker. 250mg/day showed no effect — clear dose threshold.
Fulvic acid inhibits tau protein fibril aggregation and can disassemble pre-formed fibrils in vitro. Promising mechanism for neuroprotection, but no human clinical trials yet.
Most clinical trials used PrimaVie purified extract in capsule form. This is the most practical form for consistent dosing and quality assurance. Always choose products with batch-specific COA for heavy metals.
Taste: Bitter, earthy, strongly mineral. Unmistakably geological — this tastes like it came from a mountain.
Traditional resin form — purified shilajit in its natural tar-like consistency. Harder to dose precisely than capsules. Requires high trust in supplier's purification and testing. Visually indistinguishable from common adulterants like ozokerite.
Shilajit has a small but genuinely promising evidence base, anchored by two standout trials for testosterone support and male fertility.
The testosterone data (notable):
Pandit 2016 (n=75) gave 500mg/day of purified shilajit (PrimaVie) to healthy men aged 45-55 for 90 days. Total testosterone +20.45%, free testosterone +19.14%, DHEA +31.35% (all p<0.05). LH and FSH well-maintained. These were healthy men with normally functioning hormonal axes — most adaptogens show effects only in stressed or deficient populations. The DHEA increase suggests upstream adrenal support rather than gonadal stimulation alone.
The fertility data (strong effect sizes):
Biswas 2010 (n=60) treated infertile men with oligospermia using 200mg/day for 90 days. Sperm count +61.4% (p<0.001), motility +17%, morphology +18.9%, testosterone +23.5%. Oxidative stress marker MDA -18.7%. Large effect sizes across multiple endpoints.
The exercise data (dose-dependent):
Keller 2019 found that 500mg/day preserved maximal voluntary isometric contraction strength after a fatiguing protocol (p=0.024) and reduced a marker of collagen degradation. The 250mg/day dose showed no effect — a clean dose-response finding from an independent US lab, encouraging because the testosterone and fertility work comes from overlapping research groups.
The cognitive angle (preclinical only):
Fulvic acid — shilajit’s primary bioactive — inhibits tau protein fibril aggregation in vitro and can disassemble pre-formed fibrils. Tau aggregation is a hallmark of Alzheimer’s pathology. Mechanistically plausible, but no human cognitive trials exist.
Limitations:
The testosterone and fertility evidence rests on two clinical trials from overlapping research teams. The effect sizes are notable and the findings consistent, but this is not a deep evidence base. Independent replication would dramatically strengthen confidence. Treat these results as promising rather than established.
Ayurveda (3,000+ years):
Unani medicine:
Geological origin: Unlike most Ayurvedic medicines, shilajit is mineral rather than plant-derived — compressed plant matter transformed by geological pressure and microbial activity, seeping as dark resin from rock faces at 3,000-5,000m elevation. Classical texts classify types by source-rock metal content (gold, silver, copper, iron).
Purification: Classical texts mandate Shodhana before use — Triphala decoction, filtration, sun-drying. Raw shilajit was recognized as requiring processing thousands of years ago.
Capsules (recommended — most practical, most studied):
The clinical trials used purified shilajit extract in capsule form. This is the easiest way to dose consistently and the form most likely to have proper quality testing. Look for products using PrimaVie or equivalent standardized extracts with documented fulvic acid content (20-60%) and batch-specific heavy metal COA.
Resin (traditional — harder to quality-control):
The traditional tar-like resin dissolved in warm water or milk. A pea-sized portion (roughly 300-500mg) is the standard serving. The experience is distinctly earthy and mineral — this tastes like it came from a mountain because it did. The problem: resin is harder to dose precisely, and visually indistinguishable from common adulterants like ozokerite or coal tar. You need absolute trust in your supplier.
Week 1: 250mg once daily with food. Assess tolerance — watch for any GI discomfort.
Week 2 onward: 250mg twice daily (500mg/day total). This is the dose used in Pandit 2016 (testosterone) and Keller 2019 (exercise performance). Take one dose morning, one evening, with meals.
Duration: Run for a minimum of 8 weeks, ideally the full 90 days used in the testosterone trials. Effects build gradually — this isn’t something you’ll feel overnight.
For fertility specifically: The Biswas study used a lower dose (200mg/day) with strong results, but this was in a deficient population. If fertility is your primary goal, work with your doctor, get a baseline semen analysis, and consider the 200-500mg/day range depending on their guidance.
Don’t rush the evaluation. The studies that showed results ran for 90 days.
Before starting (baseline week):
During trial (weekly check-ins):
At 90 days:
When to stop:
What they report: Gradual improvements in energy, vitality, exercise recovery. For some, noticeable libido changes. The effects tend to be subtle and cumulative rather than dramatic.
With shilajit, sourcing isn’t a nice-to-have — it’s the difference between a promising supplement and a source of heavy metal poisoning.
Shilajit is a geological exudate from rock. It concentrates whatever metals are in the source rock — lead, arsenic, cadmium, mercury. This is inherent to the material’s nature. Raw, unpurified shilajit is unsafe for human consumption.
The traditional Shodhana (purification) process — Triphala decoction, filtering, sun-drying — reduces impurities but predates analytical chemistry. It may not meet modern parts-per-billion safety thresholds.
The shilajit market is severely compromised. Common adulterants include:
You cannot distinguish genuine shilajit from these adulterants by appearance, smell, or taste. Only lab testing confirms authenticity.
No pharmacopoeial monograph exists for shilajit — not in the Ayurvedic Pharmacopoeia of India, WHO, EMA, or USP. Despite millennia of use, there are no internationally recognized quality standards. You are entirely dependent on manufacturer integrity and third-party testing.
PrimaVie is the extract used in the clinical trials — a reference point for what “tested and documented” looks like, not a product endorsement.
If a shilajit product cannot provide a current, batch-specific COA with heavy metal results, do not buy it.
When it works: Notable testosterone and fertility support — +20% total testosterone in healthy men, +61% sperm count in infertile men. Gradual improvements in energy, vitality, and exercise recovery.
When it doesn’t: Small evidence base means it may not replicate. Two key studies, overlapping researchers, no meta-analyses. If you need certainty before trying, this isn’t there yet.
When to be careful: The supply chain is the primary safety threat. Only purified extracts with batch-specific heavy metal testing. No COA, no purchase.
If the sourcing is right and you’re a reasonable candidate, a 90-day trial at 500mg/day is a reasonable experiment. Track honestly, get blood work if you’re serious about testosterone goals, and give it the full three months the studies used.
Duration: Minimum 8 weeks, optimal 12 weeks (90 days). Both key testosterone studies ran for 90 days. Effects are gradual, not immediate.
What to notice:
Start with 250mg once daily for the first week to assess tolerance, then increase to 250mg twice daily (500mg/day) — the dose used in the testosterone and exercise trials. Take with food. Effects build gradually over weeks. The 90-day trial duration in the key studies isn't arbitrary — give it the full three months before deciding. If you're trying this for fertility, work with your doctor and get baseline semen analysis first.
Generally considered: caution
Contraindications:
Pregnancy/Nursing: Avoid entirely. No safety data exists for pregnancy or breastfeeding. The heavy metal contamination risk is especially concerning during fetal development and lactation, even with purified products.
The safety profile of purified, tested shilajit appears good in clinical trials — no serious adverse events in any study (combined n=198, up to 90 days). The danger is in the supply chain, not the substance itself. Raw shilajit concentrates lead, arsenic, cadmium, and mercury from source rock. May interact with blood sugar medications (enhanced hypoglycemic effect), anticoagulants, immunosuppressants, thyroid medications, and blood pressure medications. Fulvic acid's bioavailability-enhancing properties may increase absorption of co-administered drugs. No pharmacopoeial monograph exists (absent from API, WHO, EMA, USP) despite millennia of Ayurvedic use — a notable regulatory gap.