Shilajit: A Comprehensive Reference
1. Identity, Natural Source, and Common Forms
Names and Nomenclature
Shilajit (also rendered Shilajatu or Silajatu in classical Sanskrit texts) is a phytomineral exudate classified in modern botanical nomenclature under the Latin designation Asphaltum punjabianum. It is also known as Mumie or Mummio in Russian, Hajar-ul-musa in Arabic, Asphalt, Mineral Pitch, and Jew's Pitch in English, Asphaltum in Latin, and Bitumen mineral in botanical terminology. In Sanskrit, "shila" means rock and "jit" means having won, yielding the interpretation "conqueror of mountains and destroyer of weakness."
Physical Description
Shilajit is a sticky, brown-to-blackish physiologically active organic matter that exudes from steep rocks in many mountain ranges of the world, especially the Himalayas of the Indian subcontinent. It is composed of rock humus, rock minerals, and organic substances that have been compressed by layers of rock mixed with marine organisms and microbial metabolites.
Geographic Origin and Formation
Shilajit originates from decomposed plant material trapped in high-altitude rock formations, mainly in the Himalayan, Altai, and other mountain ranges. Among these, the Himalayas are considered the most revered source. Over centuries, the pressure from rock formations and extreme weather conditions break down this organic matter, turning it into a rich, tar-like resin.
Formation begins with the decomposition of prehistoric plant life, including species such as Euphorbia royleana and Trifolium repens. As these plants die, they become trapped within layers of mountain rock. Over time, the weight of the mountains exerts immense pressure on this organic material. Combined with extreme temperature fluctuations—bitter cold winters and intense summer sun—microorganisms slowly break down the plant matter. This process, known as humification, turns the vegetation into a nutrient-rich humus that eventually becomes the dense, resinous shilajit.
Beyond the Himalayas, another prominent region for shilajit extraction is the Altai Mountains in Central Asia. Other locations include the Karakoram Range (northern Pakistan and India), the Pamir Mountains of Tajikistan, the Gilgit-Baltistan region of Pakistan, and the Tibetan Plateau. It can also be sourced from the Caucasus Mountains and the Andes.
Common Preparations and Commercial Forms
Shilajit is commercially available in several forms: as a raw or purified resin (the traditional and arguably most concentrated form), as powder (often encapsulated), as standardized capsules or tablets, and more recently as gummies or liquid drops. ConsumerLab tested eight popular shilajit supplements including capsules, tablets, gummies, and resins, finding that amounts of fulvic acid varied nearly 32,000%, ranging from just 6.9 mg to 2,206 mg per serving. Shilajit resins were found to contain far less fulvic acid than extracts in capsules and pills.
Purified preparations are standardized primarily on the basis of their fulvic acid content and the concentration of oxygenated dibenzo-α-pyrones (DBPs). Standardization of purified shilajit compositions is controlled so that the composition contains at least 0.3%, preferably 0.4–1%, of oxygenated dibenzo-α-pyrones, including monomers and dimers of 3,8-dihydroxydibenzo-α-pyrones, as determined by HPLC analysis.
2. Traditional and Historical Use
Ayurveda: India
The recorded history of shilajit begins with India's classical Ayurvedic tradition. Shilajit appears prominently in two of Ayurveda's most foundational texts: the Charaka Samhita and the Sushruta Samhita. The Charaka Samhita dates to approximately the first or second century CE, while the Sushruta Samhita was likely compiled around the sixth century CE. Both texts describe shilajit as a powerful rasayana, a category of substances believed to promote longevity, vitality, and rejuvenation.
Early Ayurvedic writings from the Charaka Samhita describe shilajit as a cure for all diseases as well as a Rasayana (rejuvenator) that promises to increase longevity. According to the ancient Ayurvedic text Sushruta Samhita, during the summer months of Jeshta and Ashada, mountains get heated as a result of the sun's direct rays melting their layers, which produces Shilajatu, a resin-like semisolid liquid.
Common traditional uses in Ayurveda include its action in genitourinary disorders, jaundice, digestive disorders, enlarged spleen, epilepsy, nervous disorders, chronic bronchitis, and anemia. Shilajit was also used for the treatment of kidney stones, edema, and hemorrhoids, as an internal antiseptic, and to reduce anorexia. It was also claimed in India to be used as yogavaha—a synergistic enhancer of other drugs.
Shilajit is a widely used natural herbo-mineral in Ayurveda, the traditional Indian system of medicine. It was traditionally administered dissolved in warm milk or water, and was combined with other herbs and natural substances as part of compound formulations.
Other Cultures and Traditions
Ancient peoples across Nepal, Tibet, Pakistan, and China also used shilajit independently. Greek philosopher Aristotle may have known about it as well, suggesting its reputation spread across cultures even in ancient times. Ibn Sina, also known as Avicenna, was an 11th-century Persian physician and philosopher who also referenced the substance in his medical writings.
In Russian and Central Asian folk medicine, where it is called Mumie or Mummio, the substance has been used for centuries in the treatment of bone fractures, wounds, and to restore energy. The Altai region of Russia has its own longstanding tradition of shilajit use.
3. Key Constituents and Active Compounds
Overview of Chemical Composition
Shilajit is composed of humus and organic plant material, and its active constituents include dibenzo-alpha-pyrones, dibenzo-alpha-pyrone-chromoproteins, and fulvic acids. A foundational review published in PMC confirmed that humic components, including humins, humic acids, and fulvic acids, are found in all shilajit preparations.
Fulvic Acids
The review identified fulvic acids as the biologically active compound, along with dibenzo-alpha-pyrones which act as carriers of other substances. Fulvic acid is a complex mixture of low-to-medium molecular weight organic acids (typically Mn 700 to 2,000 in quality shilajit preparations) with a highly variable composition. Fulvic acid's small molecular weight confers its role as a carrier molecule, enabling it to cross cell membranes and transport associated minerals and bioactive compounds into cells.
Dibenzo-Alpha-Pyrones (DBPs)
A particular focus of purified shilajit compositions is providing an abundance of bioactive components, particularly oxygenated dibenzo-α-pyrones (DBPs), and carrier molecules, which are low-to-medium molecular weight fulvic acids (FAs) present in abundant amounts in the composition. The purified shilajit composition includes mono- or di-hydroxy or tetrameric dibenzo-α-pyrones (DBP) and fulvic acids (FAs). The methanol-soluble portion also includes 3-OH dibenzo-α-pyrone; 3,8-diOH dibenzo-α-pyrone; eicosapentaenoic acid; docosapentaenoic acid; docosahexaenoic acid; 2-hydroxyacetophenone; 2,4-dihydroxyacetophenone; and α-lipoic acid.
Humic Substances and Other Fractions
The humic fraction of shilajit consists of three broad sub-classes: fulvic acids (lowest molecular weight, fully water-soluble across all pH values), humic acids (higher molecular weight, soluble only in alkaline conditions), and humins (highest molecular weight, insoluble at any pH). The purified shilajit composition is also characterized by the presence of humic acid, humins, polyphenolics, terpenoids, phytosteroids, amino acids, metal ions, moisture, and mineral metallic ions.
Mineral Content
Shilajit contains a broad array of trace minerals absorbed from surrounding rock formations during its formation. Shilajit heavy metals (iron, zinc, chromium, manganese, cobalt, and lead) have been determined and in properly purified products are at the permitted level as indicated by the World Health Organization (WHO). The presence of chromium, zinc, and iron has been specifically noted in relation to metabolic and hematological functions.
4. Established and Proposed Mechanisms of Action
Antioxidant Activity
Shilajit is composed of humus and organic plant material, and exhibits antioxidant, immunomodulatory, anti-inflammatory, adaptogenic, and antidyslipidemic activities. The fulvic acid and DBP fractions are the primary contributors to antioxidant capacity; fulvic acid donates electrons to neutralize reactive oxygen species (ROS).
Mitochondrial Energy Metabolism and CoQ10 Interaction
A key proposed mechanism relates to the interaction between shilajit's DBPs and cellular coenzyme Q10 (CoQ10). The effect of shilajit on enhancing the anti-fatigue effects of CoQ10 is attributed to increased mitochondrial biogenesis and reduced oxidative stress, as published in Pharmacology, Biochemistry and Behavior. DBPs are proposed to function as electron carriers in the mitochondrial electron transport chain, stabilizing and recycling CoQ10 to its reduced (active) form.
Cognitive and Neuroprotective Mechanisms
Fulvic acid, the main active principle of shilajit, blocks tau self-aggregation, opening an avenue toward the study of Alzheimer's therapy. Tau protein hyperphosphorylation and aggregation into neurofibrillary tangles is a hallmark of Alzheimer's disease, and in vitro evidence suggests fulvic acid disrupts this process.
Hormonal and Reproductive Mechanisms
Shilajit is proposed to stimulate the hypothalamic-pituitary-gonadal axis and reduce oxidative stress affecting hormone production. Shilajit has also been shown in animal models to enhance testosterone biosynthesis by activating enzymes such as 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-HSD.
Blood Glucose Regulation
Fulvic acid in shilajit acts similarly to exercise by increasing metabolism and ATP consumption, and protecting mitochondrial membrane potential, which is important for correcting levels of insulin and glucose in the blood. Shilajit also contains chromium and can decrease the glycation of hemoglobin, which is relevant to managing diabetes.
Immunomodulation
Shilajit exhibits immunomodulatory and anti-inflammatory activities, as well as cholinergic and parasympathomimetic effects. However, the immunomodulatory activity does not stand the test of critical assessment and currently may be considered unproven, and the overall bioactivity of shilajit lacks substantial evidence in this domain.
5. Scientific Evidence by Area of Use
5.1 Testosterone and Male Reproductive Health
This is the area with the strongest human clinical evidence for shilajit.
Testosterone in healthy men: Purified shilajit was evaluated in healthy volunteers aged 45 to 55 years in a randomised, double-blind, placebo-controlled clinical study at a dose of 250 mg twice daily. Treatment for 90 consecutive days revealed significantly (P < 0.05) increased total testosterone, free testosterone, and dehydroepiandrosterone (DHEAS) compared with placebo. Gonadotropic hormones (LH and FSH) levels were well maintained.
This most frequently cited human study was a 90-day randomised, placebo-controlled trial in healthy adult men using a purified, standardised shilajit extract. The researchers reported statistically significant changes in total and free testosterone markers in the shilajit group compared with placebo. It is one trial in a healthy population, and while it is useful peer-reviewed human data, it is not the final word.
Spermatogenic activity in oligospermia: A second study examined 28 men diagnosed with oligospermia. Published in Andrologia in 2010, this clinical study evaluated processed shilajit at 100 mg twice daily for 90 days, reporting a 23.5% increase in serum testosterone, 61.4% increase in total sperm count, and significant improvements in sperm motility and morphology.
Limitations: This is still one product-specific trial in a healthy population, and should not be presented as final proof that every shilajit product raises testosterone in every man. The oligospermia study was small (n=28) and lacked a placebo arm by modern standards.
5.2 Physical Performance, Muscle Strength, and Fatigue
Muscular strength and connective tissue: Shilajit is described as a fulvic mineral complex exudate composed of fulvic acids, dibenzo-α-pyrones, proteins, and minerals. A study examined the effects of 8 weeks of shilajit supplementation at 250 mg/day (low dose) and 500 mg/day (high dose) versus placebo on maximal voluntary isometric contraction (MVIC) strength, concentric peak torque, fatigue-induced percent decline in strength, and serum hydroxyproline (HYP) in 63 recreationally-active men, randomly assigned to high-dose, low-dose, or placebo groups.
Results demonstrated that 8 weeks of PrimaVie® shilajit supplementation at 500 mg/day promoted the retention of maximal muscular strength following a fatiguing protocol and decreased baseline hydroxyproline (HYP). Thus, PrimaVie® shilajit supplementation at 500 mg/day elicited favorable muscle and connective tissue adaptations.
28-day pilot study: Shilajit is a mineral-rich natural exudate traditionally used as a rejuvenator and performance enhancer. While previous studies have evaluated standardized extracts, there is limited clinical evidence on the traditional resin formulation. A 28-day open-label, single-arm pilot clinical study was conducted in 25 healthy male participants aged 21–55 years. Participants received 500 mg/day of TruBlk™ Shilajit Resin (250 mg twice daily), with primary outcomes including changes in muscle strength (one-repetition maximum leg press), muscle endurance, grip strength, fatigue severity, and rating of perceived exertion.
Chronic fatigue syndrome (CFS): A systematic review and meta-analysis on the effect of shilajit on chronic fatigue syndrome (CFS)-related parameters in animal and human studies was published in the Journal of Basic and Clinical Physiology and Pharmacology, volume 34, 2023. A study published in the Journal of Ethnopharmacology in 2012 reported that shilajit reduced symptoms of chronic fatigue syndrome by reducing physical and mental stress and improving cellular function and energy. The evidence base from human studies remains limited and the quality of the overall body of evidence is preliminary.
5.3 Cognitive Function and Neuroprotection
Alzheimer's disease — laboratory and preclinical evidence: A 2023 laboratory study found that shilajit from northern Chile might help slow the progression of Alzheimer's disease by affecting amyloid protein formation in the brain. However, these findings come from laboratory studies, not human trials. The leap from test-tube results to real-world cognitive benefits requires extensive clinical research that has not yet been completed.
Fulvic acid, the main active principle, blocks tau self-aggregation, opening an avenue toward the study of Alzheimer's therapy — an in vitro finding that has not yet been replicated in large human trials.
Animal models: Mice given shilajit extracts showed improvements in memory tasks and reduced amyloid-beta load. Cell culture studies: Neurons treated with fulvic acid demonstrated greater survival under toxic conditions. Small human trials: Preliminary data suggest mild cognitive improvements in older adults with subjective memory complaints; larger, long-term trials are underway.
More investigations at the basic biological level are necessary, and well-developed clinical trials are needed in order to understand how the active principles of shilajit act at molecular and cellular levels.
Evidence strength: Preclinical (in vitro and animal) evidence is promising, but human clinical evidence for cognitive outcomes remains preliminary and insufficient to support therapeutic claims.
5.4 Blood Glucose Regulation and Diabetes
A key human clinical trial examined 84 Type 2 Diabetes patients treated with 500 mg Shilajit (Silajatu) twice daily for 3 months, showing significant reductions in fasting and post-prandial blood sugar levels. Preclinical evidence from the Indian Journal of Pharmacology demonstrated that shilajit reduces blood glucose and improves lipid profiles in diabetic rats, and that combining shilajit with metformin or glibenclamide enhances glucose-lowering effects beyond either drug alone.
Limitations: The human trial in type 2 diabetes had a relatively small sample and was conducted in an Ayurvedic clinical context. Independent replication in well-controlled large RCTs is lacking. Particular care is needed when taking shilajit together with antidiabetic medication, because shilajit may further lower blood sugar, creating an increased risk of hypoglycemia if used alongside medicines such as insulin or metformin.
5.5 Iron-Deficiency Anemia
Because shilajit contains iron, it may help in certain cases of mild iron deficiency, but it is not a standard medical treatment for anemia. This area is supported by the iron content of the substance rather than dedicated clinical trials for anemia as a primary endpoint. Formal clinical trial evidence for shilajit specifically as an anemia treatment is absent from the peer-reviewed literature.
5.6 Anti-inflammatory and Immunomodulatory Effects
Shilajit is a natural phytocomplex known for centuries in Ayurveda for its antioxidant, immunomodulatory, and neuroprotective properties. However, there is little published scientific evidence to support these acclaimed properties. Cell culture and animal data support anti-inflammatory activity, but human clinical trials designed specifically to evaluate anti-inflammatory outcomes are lacking.
6. Dosage Forms and Study-Reported Dosages
The following dosages are drawn exclusively from those reported in published studies and peer-reviewed sources cited above:
- 250 mg twice daily (500 mg/day) for 90 days — used in the randomised, double-blind, placebo-controlled study of testosterone in healthy men aged 45–55 (Andrologia, 2016). The dose was 250 mg twice daily in this study.
- 100 mg twice daily (200 mg/day) for 90 days — used in the spermatogenic activity study in oligospermic men (Andrologia, 2010). A clinical study in men with oligospermia used processed shilajit 100 mg twice daily for 90 days.
- 500 mg/day (high dose) and 250 mg/day (low dose) for 8 weeks — used in the muscular strength and hydroxyproline study in recreationally active men. Only the 500 mg/day dose produced significant retention of maximal muscular strength following a fatiguing protocol and decreased baseline hydroxyproline.
- 500 mg twice daily (1,000 mg/day) for 12 weeks — used in the type 2 diabetes clinical investigation. In the clinical investigation involving type 2 diabetes, participants took 500 mg twice daily, and this regimen was associated with significant improvements in blood sugar markers.
- 500 mg/day (250 mg twice daily) for 28 days — used in the open-label TruBlk™ shilajit resin pilot study. Participants received 500 mg/day of TruBlk™ Shilajit Resin (250 mg twice daily) in that pilot study.
- 500 mg/day for 56 days and 1,000 mg/day for 30 days — used in safety studies. Clinical trials have been conducted at 500 mg daily for 56 days and 1,000 mg daily for 30 days without reported safety problems.
- 2,000 mg/day for 45 days — safety study. Twenty healthy individuals received 2,000 mg shilajit capsules for 45 days without any systemic toxicity, with no significant effect on body weight, heart rate, blood pressure, glucose, urea, creatinine, uric acid, total protein albumin, and liver enzymes.
7. Safety Considerations and Drug Interactions
Heavy Metal Contamination
This is the most well-documented and serious safety concern associated with shilajit products. Raw shilajit contains heavy metals including lead, mercury, arsenic, cadmium, aluminum, chromium, and thallium, resulting from prolonged geological formation processes.
Research has consistently shown that unpurified or poorly processed shilajit can contain dangerous levels of toxic metals that accumulate in the body over time. Even low levels of lead exposure can adversely affect neurobehavioral development and cognitive function, particularly in children and developing fetuses. In adults, elevated lead levels can cause high blood pressure, anemia, and damage to the nervous and reproductive systems. Lead is of particular concern during pregnancy as mothers can transfer it to their unborn children.
It has been reported that shilajit contains significant amounts of heavy metals such as arsenic (As), lead (Pb), mercury (Hg), nickel (Ni), and cobalt (Co). This presents a challenge when considering shilajit as a dietary supplement, as heavy metal contamination can cause severe health problems.
Peer-reviewed research published in 2025 documented thallium levels of up to 0.095 µg per tablet in some commercial shilajit supplements, exceeding those found in select raw materials.
A 2025 study found that some processed shilajit supplements actually contained higher levels of toxic heavy metals than raw varieties, highlighting the importance of third-party testing and quality assurance.
Shilajit consumption without knowing permissible levels of metals is not safe and could pose serious health problems.
Variability in Fulvic Acid Content
Fulvic acid concentrations vary substantially across commercially available shilajit, primarily due to source variability and differences in extraction and standardization techniques. ConsumerLab documented fulvic acid levels ranging from 6.9 mg to 2,206 mg per serving, representing a nearly 32,000% variation. This makes product-to-product comparison and accurate dosing extremely difficult.
General Tolerability in Purified Products
Purified shilajit can be used safely in clinical research and practice. Purified, standardised, third-party tested shilajit was well tolerated in published trials. Digestive side effects such as nausea, cramps, and diarrhea are rare and occur mainly in overdose.
Drug Interactions
- Antidiabetic medications: Particular care is needed when taking shilajit together with antidiabetic medication. Because shilajit may further lower blood sugar, there could be an increased risk of hypoglycemia if it is used alongside medicines such as insulin or metformin.
- Antihypertensives and blood thinners: Interactions with blood pressure or blood-thinning medication also cannot be ruled out.
- Iron overload risk: Possible concerns include overdosage leading to iron overload in susceptible individuals.
Bioavailability as a Double-Edged Sword
Because fulvic acid is such an efficient carrier molecule, if the shilajit is contaminated, that same fulvic acid will transport toxic metals like lead and arsenic directly into cells. This paradox underscores that the very property that makes shilajit potentially beneficial — enhanced mineral and nutrient delivery — also increases the risk of harm from contaminated products.
Evidence Limitations and Overall Evidentiary Quality
Despite a long history of use in traditional Indian materia medica, shilajit unfortunately lacks systematic scientific evaluation and documentation. In vivo antioxidant activity of shilajit has been studied at irrelevant doses and without using a positive control. The overall clinical database consists of a small number of trials, most of which are single-product studies, many sponsored or conducted by parties with commercial interest in the product. Independent large-scale replication is lacking across all therapeutic areas. As of the current literature, shilajit for men is best viewed as a promising but not proven supplement. The most credible human research points to possible benefits for testosterone, sperm parameters, and exercise recovery, but the evidence base is still small, and contamination risk is a real concern.
References
- Carrasco-Gallardo C, Guzmán L, Maccioni RB. Shilajit: A Natural Phytocomplex with Potential Procognitive Activity. Int J Alzheimers Dis. 2012. PMC3296184.
- Pandit S, et al. Clinical evaluation of purified Shilajit on testosterone levels in healthy volunteers. Andrologia. 2016;48(5):570–575. PubMed PMID: 26395129.
- ScienceDirect Topics: Shilajeet — Overview. Pharmacology, Toxicology and Pharmaceutical Science.
- Keller JL, et al. The effects of Shilajit supplementation on fatigue-induced decreases in muscular strength and serum hydroxyproline levels. J Int Soc Sports Nutr. 2019. PubMed PMID: 30728074.
- 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. PubMed PMID: 38393486.
- Quantifying of thallium in Shilajit and its supplements to unveil the potential risk of consumption. PMC11743217.
- Safety and Efficacy of TruBlkâ„¢ Shilajit Resin Supplementation on Physical Performance and Blood Biomarkers in Healthy Adults: A 28-Day Open-Label Pilot Study. PMC12848467.
- ConsumerLab. Shilajit Supplements Found to Contain High Amounts of Fulvic Acid (and Some with Heavy Metals). 2024.
- Shilajit, a Natural Phytocomplex Acts as a Neuroprotective Agent Against Amyloid Beta-induced Cytotoxicity and Inflammation. Integrative Medicine Research.
- Unlocking the potential of Shilajit in Vascular Dementia — A concise review. ScienceDirect / Phytomedicine Plus. 2025.
- Shilajit (Mumie): A natural Product with Anti-hyperglycemic, Anti-obesity, Anti-oxidant, and Anti-Inflammatory properties for a potential treatment of diabetes mellitus. Jordan Journal of Biological Sciences. ResearchGate.
- Shilajit mitigates chemotherapeutic drug-induced testicular toxicity: Study on testicular germ cell dynamics, steroidogenesis modulation, and Nrf-2/Keap-1 signaling. PubMed PMID: 39121783.
- US Patent 6,869,612 — Process for preparing purified shilajit composition from native shilajit. USPTO.
- Cleveland Clinic Health Essentials. Shilajit Benefits, Side Effects and Uses. 2025.
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