Shilajit: Evidence, Dosage and Quality Markers

Medically reviewed by Dr Zeeshan Afzal (MBBS), Medical Officer at Welzo. Last updated: July 2026. This article is for general information only and is not a substitute for personalised medical advice.

Shilajit has moved from obscure Ayurvedic curiosity to one of the fastest-growing categories in the British supplement market. Search interest in shilajit UK has climbed sharply, driven largely by claims about testosterone, energy and stamina. But the category also carries a genuine safety problem: shilajit is a mineral-rich substance scraped from rock, and unpurified material has repeatedly been shown to contain heavy metals.

For where shilajit sits among the alternatives, start with our pillar guide to longevity supplements and browse the wider anti-ageing and longevity range. If you are building a broader regimen, it pairs with our complete guide to NMN benefits, side effects and dosage and our range of NMN supplements.

This guide separates what the human evidence actually supports from what is marketing. It covers realistic dosing, the quality markers that matter when buying in the UK, and the specific red flags that distinguish a properly processed extract from a jar of unverified resin.

Key Takeaways

• The human evidence is small but real. Four or five human trials exist, mostly on one standardised extract, mostly small, and several funded by the ingredient supplier.
• Studied doses cluster at 250–500 mg per day of a purified, standardised extract — not the multi-gram doses sometimes suggested for raw resin.
• Purification is not optional. Raw shilajit can contain lead, arsenic, mercury, cadmium and thallium. This is the single most important safety issue in the category.
• Fulvic acid percentage alone is a weak quality marker. Batch-specific heavy metal testing by ICP-MS matters more.
• In the UK, shilajit is sold as a food supplement, not a medicine. No UK body pre-approves it for efficacy, and no disease claims are legally permitted.
• It is not a testosterone treatment. If you suspect low testosterone, get a blood test through your GP rather than self-treating.

Table of Contents

• What Is Shilajit?
• What Shilajit Actually Contains
• What the Evidence Says: A Realistic Assessment
• Evidence Strength at a Glance
• Shilajit Dosage: How Much and When
• Resin, Capsules, Powder or Gummies?
• Quality Markers: The UK Buyer's Checklist
• Heavy Metals and Contamination Risk
• How Shilajit Is Regulated in the UK
• Side Effects, Interactions and Who Should Avoid It
• How to Spot Fake or Adulterated Shilajit
• Stacking Shilajit With Other Supplements
• Realistic Expectations and Timelines
• Frequently Asked Questions
• References

What Is Shilajit?

Shilajit is a blackish-brown, tar-like exudate that seeps from crevices in high-altitude rock during warmer months. It is not a plant, a mineral or an animal product in the conventional sense — it is a geological-biological hybrid, formed over centuries as plant matter compresses and humifies within rock strata.

Deposits are found across the Himalayas, the Karakoram, the Pamir range, the Altai and Caucasus mountains, and parts of Iran and Central Asia. Because the source rock differs between regions, so does the composition — which is precisely why standardisation matters so much in this category.

Traditional Use and Names

In Ayurveda, shilajit is classed as a rasayana — a rejuvenating tonic. The Sanskrit name is usually rendered as "conqueror of rock". Elsewhere it is known as mumijo or mumie (Russian and Central Asian traditions), brag-shun in Tibetan medicine, and moomiyo in Persian sources. Traditional use spans several thousand years and multiple medical systems.

Traditional use is a reason to investigate a substance. It is not, on its own, evidence that it works — a distinction we apply consistently across our longevity supplements guide.

Raw Versus Purified

Raw shilajit scraped from rock contains sand, plant debris, microbial contamination and, frequently, heavy metals. Traditional purification (shodhana) involves dissolution in water, filtration and sun-drying. Modern processing adds controlled temperature extraction, centrifugation and analytical verification.

Every credible clinical trial on shilajit has used a purified, standardised extract. None has used raw resin. This is the most important thing to understand before you buy anything.

What Shilajit Actually Contains

Around 60–80% of shilajit by weight is humic substances — chiefly fulvic acid and humic acid. The remainder includes dibenzo-alpha-pyrones (DBPs), small peptides, amino acids, and a mineral fraction typically representing 15–20% of the material.

The Main Constituents

Why "80+ Minerals" Is a Weak Selling Point

Marketing frequently emphasises that shilajit contains 80 or more trace minerals. This is technically accurate and practically almost meaningless. At a 500 mg daily dose, the absolute quantity of any individual mineral is negligible against dietary intake — and the same geological process that deposits selenium and magnesium also deposits lead and arsenic. A long mineral list is a description of where the material came from, not a benefit.

The constituent with the most published mechanistic work behind it is fulvic acid, and the extract most used in trials is standardised to a defined fulvic acid and DBP content rather than sold on mineral count.

What the Evidence Says: A Realistic Assessment

Shilajit sits in an awkward middle ground. It is not an unstudied novelty, but nor is it well evidenced. There are a handful of human randomised controlled trials, several open-label studies, and a much larger body of rodent and in-vitro work. Most human trials share three limitations: small samples, short duration, and funding or material supplied by the ingredient manufacturer.

Testosterone in Middle-Aged Men

The most cited human study is a randomised, double-blind, placebo-controlled trial published in Andrologia in 2016. Healthy male volunteers aged 45–55 took 250 mg of purified shilajit twice daily for 90 days. The shilajit group showed statistically significant increases in total testosterone, free testosterone and DHEAS compared with placebo, while gonadotropins (LH and FSH) remained stable.^[1]

Two caveats matter. First, the sample was small and the participants were healthy men in an age band where testosterone is naturally declining — the finding may not transfer to younger men or those with clinically diagnosed hypogonadism. Second, a 2024 systematic review in the International Journal of Impotence Research examining "testosterone booster" supplements as a class found that the great majority of marketed ingredients lack convincing evidence of raising serum testosterone, with only a minority showing any effect.^[2]

What This Means Practically

Shilajit is not a treatment for low testosterone. If you have symptoms such as persistent fatigue, low libido, mood changes or loss of muscle mass, the appropriate step is a blood test through your GP — not a supplement. Men building a general regimen may find our guide to longevity supplements for men over 50 more useful as a starting framework.

Sperm Parameters

A separate clinical study published in Andrologia examined processed shilajit at 100 mg twice daily for 90 days in men with oligospermia, reporting improvements in sperm count and motility.^[3] This was a small, uncontrolled-arm study in a specific clinical population and should be read as preliminary rather than conclusive.

Muscle Strength and Connective Tissue

This is arguably the most methodologically sound area. A 2019 randomised, double-blind, placebo-controlled trial in the Journal of the International Society of Sports Nutrition gave 63 recreationally active men either 250 mg/day, 500 mg/day, or placebo for eight weeks. The 500 mg group better retained maximal voluntary isometric contraction strength following a fatiguing protocol, and showed reduced baseline serum hydroxyproline — a marker of collagen breakdown.^[4]

A related 2016 study in the Journal of Medicinal Food took muscle biopsies from 16 overweight adults taking 250 mg twice daily for eight weeks, followed by four weeks with exercise. Researchers found upregulation of extracellular matrix genes including collagen, elastin, fibronectin and decorin. Supplementation was well tolerated with no adverse changes in glucose, lipids, creatine kinase or myoglobin.^[5] This was open-label with no placebo group, so gene expression changes cannot be cleanly separated from time and exercise effects.

If connective tissue resilience is your primary goal, it is worth comparing shilajit against better-evidenced options — see our comparisons of creatine for longevity and supplements for endurance athletes.

Energy and Mitochondrial Function

The mechanistic rationale here rests on DBPs acting within the electron transport chain and fulvic acid's antioxidant activity. Fulvic acid from shilajit has demonstrated complement-fixing and immunomodulatory activity in laboratory work.^[6] However, there is no large, well-controlled human trial demonstrating that shilajit meaningfully increases subjective energy or measured ATP production in healthy adults. Claims of "cellular energy" are extrapolated from mechanism, not established outcomes.

If sustained energy is your actual goal, NAD⁺ precursors have a considerably larger human literature. See our NAD supplement guide and NMN vs creatine comparison.

Cognition

A widely cited 2012 review in the International Journal of Alzheimer's Disease proposed that fulvic acid may inhibit tau protein self-aggregation, a mechanism relevant to neurodegeneration.^[7] This is preclinical work. There is no adequately powered human trial showing shilajit improves memory or slows cognitive decline. Any product marketing it as a nootropic or dementia intervention is overreaching, and in the UK such claims are not legally permitted for a food supplement.

Where the Evidence Is Genuinely Weak

A comprehensive review of shilajit in traditional Indian medicine published in the Journal of Ethnopharmacology concluded that claimed antioxidant and immunomodulatory effects lack robust scientific validation, and that quality control is a persistent problem in the literature itself.^[8] Claims relating to altitude sickness, diabetes, cholesterol, anxiety and immunity are not supported by adequate human data. We take the same sceptical line elsewhere — see longevity supplements that don't work.

Evidence Strength at a Glance

Shilajit Dosage: How Much and When

Almost all human trial data sits within a narrow band: 250 mg to 500 mg per day of a purified, standardised extract. Higher doses seen on some product labels — one or two grams of raw resin daily — have no supporting trial data and increase cumulative contaminant exposure proportionally.

Evidence-Aligned Dosing

Timing and Food

No trial has directly tested timing. Trial protocols generally used twice-daily dosing without specifying food status. Practically, most people take shilajit in the morning because a subset report it feeling mildly stimulating. If you experience nausea — the most commonly reported minor side effect — taking it with food usually resolves it.

For broader guidance on sequencing a regimen, see our supplement timing chart, whether supplements should be taken on an empty stomach, and whether you can take supplements together.

Starting Sensibly

Begin at the low end — 250 mg daily — for two weeks before considering an increase. This is standard practice for any new supplement and is covered in more detail in our guide on how to start longevity supplements.

Resin, Capsules, Powder or Gummies?

Resin has strong cultural authenticity appeal, and that appeal is doing a lot of work in this market. The practical reality is that a jar of resin gives you no reliable way to measure a dose and no guarantee that any given scoop reflects the batch that was tested. Capsules of a standardised extract are the format the research actually supports.

Quality Markers: The UK Buyer's Checklist

Because no UK authority pre-approves supplement efficacy, quality is effectively self-policed. The following markers separate a defensible product from an expensive unknown.

1. A Batch-Specific Certificate of Analysis

Not a generic PDF for "our shilajit" — a document matching the batch number printed on your jar or bottle. It should name the testing laboratory, the test date and the batch. If a brand cannot produce this on request, that is a complete answer. Read our detailed explainer on what a supplement certificate of analysis should contain.

2. Heavy Metal Testing by ICP-MS

Inductively coupled plasma mass spectrometry is the industry standard, detecting contaminants at parts-per-billion. At minimum you want results for lead, arsenic, mercury and cadmium. Given recent findings, thallium is worth asking about too.

3. Independent Third-Party Testing

In-house testing is better than nothing but is not independent. Look for an ISO 17025-accredited laboratory. Our guide to third-party tested supplements explains how to verify these claims rather than take them at face value.

4. Standardisation, Not Just a Fulvic Acid Number

Fulvic acid content varies enormously between products — independent testing has found order-of-magnitude differences between shilajit supplements on the market. A stated percentage is only meaningful if it is verified on the COA and expressed against a defined analytical method. Be sceptical of claims above 70–80% fulvic acid, which are difficult to achieve in a genuine shilajit extract and often reflect a different assay being used.

5. GMP Manufacturing and Clean Labelling

Look for Good Manufacturing Practice certification and a full ingredient declaration. Proprietary blends that hide individual quantities are a compliance concern under UK food supplement labelling rules. See our breakdown of supplement fillers and what they mean.

6. Transparent Sourcing

A brand should be able to tell you the region of origin and the purification method. Vague references to "the Himalayas" without further detail tell you nothing.

Quality Checklist Summary

Heavy Metals and Contamination Risk

This is the defining safety issue for the category and deserves plain treatment.

A 2024 review in Biological Trace Element Research examined heavy metals and humic substances in shilajit specifically, addressing toxicity and detoxification mechanisms.^[9] The underlying issue is straightforward: shilajit forms in rock, and rock contains what rock contains. Lead, arsenic, cadmium and mercury are all documented in raw material.

More recent analytical work has also identified thallium in commercially available shilajit supplements — in some cases at higher concentrations in the finished product than the raw material, suggesting that testing the raw ingredient alone is insufficient. Independent testing by consumer laboratories has generally found heavy metal levels in finished shilajit products to be below thresholds of concern when taken at a single daily serving, but the same testing found enormous variation in fulvic acid content between products.

What This Means for You

• Never consume raw, unprocessed resin bought informally or imported without documentation.
• Insist on batch-level heavy metal data, not raw-material data.
• Do not exceed studied doses — contaminant exposure scales with intake.
• Avoid shilajit entirely during pregnancy and breastfeeding, and in children.
• Home methods such as boiling do not remove heavy metals.

How Shilajit Is Regulated in the UK

Shilajit is sold in Great Britain as a food supplement. It falls under food supplement legislation and general food safety law, overseen by the Food Standards Agency. Novel food status is assessed under assimilated Regulation (EU) 2015/2283, and the FSA maintains a register of authorised novel foods.^[10]

Three practical consequences follow:

No Pre-Market Efficacy Approval

Unlike a licensed medicine, a food supplement does not need to demonstrate that it works before going on sale. It must be safe, accurately labelled and manufactured under controlled conditions — that is the whole of the requirement.

No Medical Claims Permitted

The MHRA regulates medicinal claims. A shilajit product that claims to treat, cure or prevent disease — "treats low testosterone", "cures fatigue" — is making an unlicensed medicinal claim. Herbal products making medicinal claims require a Traditional Herbal Registration or marketing authorisation.^[11] Shilajit products are not sold under THR.

Quality Is Brand-Dependent

Because the regulatory floor is safety and labelling rather than efficacy, two shilajit products on the same shelf can differ by an order of magnitude in active content. This is a recurring theme across the supplement market and one reason prices vary so widely — see why supplements are so expensive and our breakdown of longevity stack costs in the UK.

Side Effects, Interactions and Who Should Avoid It

A 2014 safety review in Phytotherapy Research concluded that purified shilajit appears well tolerated in the doses studied.^[12] Reported adverse effects in trials have been mild and infrequent.

Commonly Reported Effects

• Mild digestive upset, nausea or bloating
• Headache, usually at higher doses
• A metallic or earthy aftertaste, particularly with resin
• Occasional restlessness if taken late in the day

Who Should Not Take Shilajit

• Pregnant or breastfeeding women — insufficient safety data
• Children and adolescents — no established safety profile
• People with haemochromatosis or iron overload — shilajit contains iron
• People with kidney or liver disease — impaired clearance of any contaminants
• Anyone with a history of gout or elevated uric acid — discuss with your GP first
• People taking medication for blood pressure, blood sugar or thyroid function — check with a pharmacist

Before You Start

Speak to your GP or pharmacist before adding shilajit if you take prescription medication or have an existing health condition. The NHS provides general guidance on supplement use and on which vitamins and minerals have established requirements.^[13]

How to Spot Fake or Adulterated Shilajit

Adulteration is common. Cheap substitutes include bitumen, humic soil extracts, ash and coffee-derived pastes. No home test is definitive, but several are indicative.

Home Indicators

Solubility

Genuine shilajit dissolves in warm water to give a uniform, dark golden-brown to reddish solution with minimal grit. Refusal to dissolve or a heavy sediment layer suggests adulteration.

Temperature Response

Resin softens and becomes malleable with warmth and hardens when refrigerated. Material that stays uniformly soft or uniformly brittle across temperatures is suspect.

Flame Behaviour

Authentic shilajit does not readily catch flame and does not produce a strong petroleum-like smoke. Bitumen adulterants do.

The Reliable Test

None of the above replaces a batch-specific certificate of analysis. If a product cannot produce one, no kitchen-table test makes it safe.

Stacking Shilajit With Other Supplements

Shilajit is rarely taken alone. Sensible combinations depend on what you are actually trying to achieve.

Because shilajit contains iron, avoid taking it at the same time as a separate iron supplement without medical advice. Take it several hours apart from other mineral supplements where possible, since humic substances have chelating properties.

For a structured approach to building a regimen without over-buying, see our minimal supplement stack and budget longevity stack.

Realistic Expectations and Timelines

The human trials that showed effects ran for eight to twelve weeks minimum. Nothing in the literature supports the idea of a noticeable effect within days.

If you have taken a properly dosed, verified product for twelve weeks and noticed nothing, the reasonable conclusion is that it is not doing much for you. This is normal and applies to most supplements — see how long supplements take to work.

It is also worth keeping shilajit in proportion. Sleep, resistance training, protein intake and body composition exert far larger effects on the outcomes shilajit is marketed for than any resin will. Our article on the hallmarks of ageing sets out where supplementation genuinely fits.

Frequently Asked Questions

Is shilajit legal in the UK?

Yes. Shilajit is legally sold in the UK as a food supplement, provided it is safe, accurately labelled and free from prohibited substances. It cannot legally be marketed as a medicine or claim to treat, cure or prevent any disease. It is not approved by any UK body for efficacy, because food supplements do not undergo that assessment.

How much shilajit should I take per day?

Human trials have used 250–500 mg per day of a purified, standardised extract. The testosterone study used 250 mg twice daily for 90 days; the strength study used 500 mg once daily for eight weeks. Start at 250 mg and do not exceed 500 mg daily without medical advice. Doses in the gram range have no supporting trial evidence.

Does shilajit actually increase testosterone?

One randomised controlled trial in men aged 45–55 found statistically significant increases in total and free testosterone after 90 days at 500 mg daily. This is a single small study, and a 2024 systematic review of testosterone-boosting supplements as a category found most lack convincing evidence. Shilajit should not be used as a treatment for low testosterone — see your GP for a blood test instead.

Is shilajit safe? What about heavy metals?

Purified, third-party tested shilajit appears well tolerated at studied doses. Raw or unpurified shilajit is a genuine safety concern, with documented lead, arsenic, mercury, cadmium and thallium contamination in some samples. Only buy products with a batch-specific certificate of analysis showing ICP-MS heavy metal results.

Resin or capsules — which is better?

Capsules containing a standardised extract are the better choice for most people. Every human trial has used a standardised extract, not raw resin. Resin makes accurate dosing effectively impossible and carries higher contamination risk if not properly purified and tested.

How long does shilajit take to work?

Trials showing effects ran for eight to twelve weeks. Connective tissue and strength effects were measured at eight weeks; hormonal markers at ninety days. Do not expect meaningful changes in the first fortnight, and reassess after three months if you notice nothing.

Can women take shilajit?

There is no specific safety signal against use in healthy adult women, but almost all the human research has been conducted in men, so benefits are far less established. Women who are pregnant, breastfeeding or trying to conceive should avoid it. Those looking at general longevity support may find our guide to longevity supplements for women over 40 more relevant.

Should shilajit be taken with or without food?

Trials did not specify. Most people take it in the morning. If you experience nausea — the most common minor side effect — take it with food. Avoid taking it alongside separate iron or mineral supplements, as humic substances can bind minerals.

What fulvic acid percentage should I look for?

There is no established optimal figure, and independent testing has found wildly variable fulvic acid content across products. Treat any stated percentage as meaningful only if it is verified on a batch certificate of analysis with a named analytical method. Be sceptical of claims above 70–80%, which are difficult to achieve genuinely.

Can I take shilajit with NMN or other longevity supplements?

There is no documented interaction between shilajit and NAD⁺ precursors such as NMN, and they act through different mechanisms. Separate shilajit from mineral supplements by a few hours. If you take prescription medication, particularly for blood pressure, blood sugar or thyroid function, check with your pharmacist first. See our guidance on combining supplements safely.

The Bottom Line

Shilajit is more interesting than a typical wellness fad and considerably less proven than its marketing suggests. The strongest human data concerns muscle strength retention and connective tissue markers, from small trials on a single standardised extract. The testosterone evidence is one study in one narrow age band. Energy and cognitive claims rest on mechanism rather than outcomes.

If you choose to try it, the decision that matters most is not brand or price but verification: a standardised extract, 250–500 mg daily, with a batch-specific certificate of analysis showing ICP-MS heavy metal results. Anything short of that is an unnecessary risk for a modest and uncertain benefit.

References

1. Pandit S, Biswas S, Jana U, et al. Clinical evaluation of purified Shilajit on testosterone levels in healthy volunteers. Andrologia. 2016;48(5):570–575. https://pubmed.ncbi.nlm.nih.gov/26395129/
2. Morgado A, Tsampoukas G, Sokolakis I, et al. Do "testosterone boosters" really increase serum total testosterone? A systematic review. International Journal of Impotence Research. 2024;36(4):348–364. https://www.nature.com/articles/s41443-023-00763-9
3. Biswas TK, Pandit S, Mondal S, et al. Clinical evaluation of spermatogenic activity of processed Shilajit in oligospermia. Andrologia. 2010;42(1):48–56. https://pubmed.ncbi.nlm.nih.gov/20078516/
4. Keller JL, Housh TJ, Hill EC, et al. 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;16:3. https://pubmed.ncbi.nlm.nih.gov/30728074/
5. Das A, Datta S, Rhea B, et al. The Human Skeletal Muscle Transcriptome in Response to Oral Shilajit Supplementation. Journal of Medicinal Food. 2016;19(7):701–709. https://pubmed.ncbi.nlm.nih.gov/27414521/
6. Schepetkin IA, Xie G, Jutila MA, Quinn MT. Complement-fixing activity of fulvic acid from Shilajit and other natural sources. Phytotherapy Research. 2009;23(3):373–384. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2650748/
7. Carrasco-Gallardo C, Guzmán L, Maccioni RB. Shilajit: A Natural Phytocomplex with Potential Procognitive Activity. International Journal of Alzheimer's Disease. 2012;2012:674142. https://onlinelibrary.wiley.com/doi/10.1155/2012/674142
8. Wilson E, Rajamanickam GV, Dubey GP, et al. Review on shilajit used in traditional Indian medicine. Journal of Ethnopharmacology. 2011;136(1):1–9. https://pubmed.ncbi.nlm.nih.gov/21530631/
9. Hussain A, Saeed A. Hazardous or Advantageous: Uncovering the Roles of Heavy Metals and Humic Substances in Shilajit (Phyto-mineral) with Emphasis on Heavy Metals Toxicity and Their Detoxification Mechanisms. Biological Trace Element Research. 2024;202(12):5794–5814. https://pubmed.ncbi.nlm.nih.gov/38393486/
10. Food Standards Agency. Novel foods authorisation guidance. https://www.food.gov.uk/business-guidance/regulated-products/novel-foods-guidance
11. Medicines and Healthcare products Regulatory Agency. Medicines: herbal and homeopathic. GOV.UK. https://www.gov.uk/government/collections/medicines-herbal-and-homeopathic
12. Stohs SJ. Safety and Efficacy of Shilajit (Mumie, Moomiyo). Phytotherapy Research. 2014;28(4):475–479. https://pubmed.ncbi.nlm.nih.gov/23733436/
13. NHS. Vitamins and minerals. https://www.nhs.uk/conditions/vitamins-and-minerals/
14. Agarwal SP, Khanna R, Karmarkar R, et al. Shilajit: A review. Phytotherapy Research. 2007;21(5):401–405. https://pubmed.ncbi.nlm.nih.gov/17295385/
15. Khanna R, Witt M, Anwer MK, Agarwal SP, Koch BP. Spectroscopic characterization of fulvic acids extracted from the rock exudate Shilajit. Organic Geochemistry. 2008;39(12):1719–1724. https://doi.org/10.1016/j.orggeochem.2008.08.009

About This Article

Medically reviewed by Dr Zeeshan Afzal, MBBS, Medical Officer at Welzo. Dr Afzal reviews Welzo's health content for clinical accuracy and compliance with UK advertising and health claim standards.

Editorial policy: Welzo content is based on peer-reviewed research, official UK regulatory guidance and recognised clinical sources. Where evidence is limited or contested, we say so. We do not make disease treatment claims for food supplements.

Disclaimer: This article is for general information and does not constitute medical advice. Food supplements are not intended to diagnose, treat, cure or prevent any disease and should not replace a varied, balanced diet or a healthy lifestyle. Consult your GP or a qualified healthcare professional before starting any new supplement, particularly if you are pregnant, breastfeeding, taking prescription medication or living with a diagnosed medical condition.