Shilajit

Shilajit, a blackish-brown, tar-like phytocomplex, exudes from sedimentary rocks in high-altitude mountain ranges, notably the Himalayas, Altai, and Caucasus. Formed over centuries by the decomposition of plant and microbial matter, it is a cornerstone of Ayurvedic medicine, valued as a rasayana (rejuvenator) for enhancing vitality, longevity, and resilience. Rich in fulvic acid, humic substances, and minerals, shilajit is marketed as a dietary supplement for energy, cognitive health, and male fertility, though clinical evidence remains limited. This article explores shilajit’s chemical characteristics, sources, historical and modern uses, nutritional profile, pharmacological properties, clinical evidence, side effects, and practical applications, emphasizing its potential and risks.

Chemical Characteristics and Sources

Shilajit is a complex, variable substance with distinct properties:

• Chemical Composition: Comprises 60–80% humic substances (fulvic acid: 15–21%, humic acid: 5–10%), dibenzo-α-pyrones (DBPs, 0.5–5%), DBP-chromoproteins, and minerals (iron, zinc, magnesium, potassium, copper, ~18–20%). Contains trace amino acids, steroids, lipids, and plant metabolites (e.g., salicyluric acid, hippuric acid). Fulvic acid (2 kDa) is the primary bioactive, with high bioavailability.
• Physical Properties: Viscous, tar-like resin or powder, dark brown to black, with a bitter, earthy taste and cow urine-like odor. Soluble in water (30–60%, pH 6.2–8.2), insoluble in ethanol. Stable in cool, dry conditions; degrades with heat or contamination.
• Natural Source: Exudes from sedimentary rocks at 1,000–5,000 m altitudes in the Himalayas (India, Nepal), Altai, Pamir, Caucasus, Andes, and other ranges. Formed by microbial humification of plants (e.g., Euphorbia royleana, Trifolium repens) over centuries. Varies by region (e.g., Indian shilajit: 21.4% fulvic acid; Nepalese: 15.4%).
• Bioavailability: Fulvic acid is well-absorbed intestinally, peaking in plasma within 1–2 hours, eliminated within hours. Minerals have moderate bioavailability (~20–40%), enhanced by fulvic acid’s chelating properties. DBPs have low solubility, limiting absorption.
• Commercial Forms: Purified resin, powder, capsules, or liquid extracts, standardized to 5–20% fulvic acid (50–200 mg/serving). Purification removes heavy metals (e.g., lead, arsenic) and mycotoxins. Available as lauha (iron-rich, black), sauvarna (gold-infused, red), or other grades.
• Dietary Intake: Rare in diets; supplements provide 250–1,000 mg/day, delivering ~50–200 mg fulvic acid and 10–50 mg minerals, far exceeding natural exposure.

Fulvic acid and minerals drive shilajit’s purported effects, but composition varies by source.

Historical and Traditional Uses

Shilajit has a 5,000-year history in traditional medicine:

• Ancient Use: Documented in Charaka Samhita (c. 300 BCE), shilajit was used in Ayurveda as a rasayana for vitality, longevity, and disease prevention. Consumed in India, Nepal, and Tibet, often with milk or ghee.
• Traditional Medicine:
  • Ayurveda: Treated diabetes (prameha), infertility (vrishya), cognitive decline (medhya), and bone health (balya). Used for rejuvenation and stress relief.
  • Tibetan Medicine: Supported energy, digestion, and altitude adaptation, typically as a tonic.
  • Chinese Medicine: Used for kidney health and stamina, often in herbal blends.
  • Persian/Iranian Folk Medicine: Applied for bone fractures and vitality, consumed or topically.
• Culinary Use: Mixed with milk, honey, or tea in Himalayan regions (e.g., Sherpa breakfasts). Used sparingly due to potency and taste.
• Cultural Significance: Known as “conqueror of mountains” in Sanskrit, symbolizing strength and resilience. Revered by Himalayan communities for longevity.
• Modern Popularity: Gained global traction since the 2000s for energy, testosterone, and anti-aging, driven by supplement marketing and Ayurvedic resurgence.

Traditionally, purified shilajit was consumed in small doses to maximize benefits.

Nutritional Profile

Shilajit is mineral-rich but low in macronutrients. Per 500 mg of purified shilajit (standardized to 10–20% fulvic acid):

• Calories: ~1–2 kcal.
• Carbohydrates: 0.3 g (0.01 g sugars, 0.1 g fiber-like humic substances).
• Protein: 0.01 g (trace amino acids).
• Fat: 0.01 g (trace lipids).
• Vitamins/Minerals:
  • Iron: 0.1–0.5 mg (1–3% DV).
  • Zinc: 0.05–0.1 mg (0.5–1% DV).
  • Magnesium: 0.5–1 mg (0.1–0.3% DV).
  • Potassium: 1–2 mg (0.05% DV).
  • Copper: 0.01–0.02 mg (1–2% DV).
• Bioactive Compounds:
  • Fulvic Acid: 50–100 mg, antioxidant, nutrient absorption enhancer.
  • Dibenzo-α-pyrones: 2–10 mg, mitochondrial support.
  • Humic Acid: 25–50 mg, immune modulator.
• Functional Properties: High antioxidant capacity (ORAC 50–500 Trolox units/g, higher than blueberries). Fulvic acid chelates minerals, improving bioavailability; DBPs support mitochondrial energy.

Typical doses (250–1,000 mg/day) provide trace nutrients but significant bioactives.

Pharmacological Mechanisms

Shilajit’s effects stem from fulvic acid, DBPs, and minerals, based on preclinical studies:

1. Antioxidant Activity: Fulvic acid scavenges free radicals, upregulates superoxide dismutase, and reduces lipid peroxidation, protecting cells from oxidative stress.
2. Anti-inflammatory Effects: Fulvic acid inhibits IL-1β, TNF-α, and NF-κB pathways, reducing systemic and neural inflammation. Humic acid modulates immune responses.
3. Neuroprotection: Fulvic acid inhibits tau protein aggregation, potentially slowing Alzheimer’s progression. DBPs enhance cholinergic signaling, supporting memory.
4. Mitochondrial Function: DBPs and fulvic acid enhance ATP production and CoQ10 levels, reducing fatigue and supporting energy metabolism.
5. Hormonal Regulation: DBPs stimulate testosterone, FSH, and DHEAS synthesis, enhancing spermatogenesis and libido. Fulvic acid modulates dopamine and serotonin.
6. Bone Health: Minerals (zinc, copper) and fulvic acid promote collagen synthesis and osteogenic differentiation, accelerating bone repair.
7. Antiviral/Antimicrobial: Humic acids inhibit viral replication (e.g., herpes, HIV) and bacterial growth (H. pylori), supporting gut and immune health.
8. Adaptogenic Effects: Shilajit normalizes HPA axis activity, reducing stress and improving altitude adaptation via improved oxygenation.

These mechanisms, mostly from animal or in vitro studies, suggest broad therapeutic potential.

Potential Benefits

Shilajit has limited but promising evidence for several benefits:

• Male Fertility: A 2016 RCT (60 infertile men, 250 mg twice daily, 90 days) increased total sperm count by >60%, motility by 12%, and testosterone by ~23% versus placebo.
• Testosterone: The same 2016 study showed significant increases in total and free testosterone and DHEAS in healthy men (45–55 years).
• Fatigue/Energy: A 2019 RCT (63 men, 500 mg/day, 8 weeks) reduced fatigue-induced muscle strength decline by ~10% and lowered serum hydroxyproline, indicating connective tissue support.
• Bone Health: A 2022 RCT (postmenopausal women with osteopenia, 500 mg/day, 11 months) improved bone mineral density by ~5%, reducing osteoporosis risk.
• Cognitive Health: A 2012 in vitro study showed fulvic acid inhibits tau aggregation, suggesting Alzheimer’s potential; a 2023 study noted improved rat hippocampal cell growth. Human trials are lacking.
• Altitude Sickness: Anecdotal and animal data suggest shilajit improves oxygenation and reduces symptoms (e.g., headache, nausea), possibly via adaptogenic effects. No human RCTs.
• Anti-inflammatory: A 2024 study showed shilajit reduced IL-1β in a murine Alzheimer’s model; a 2018 review noted fulvic acid’s immune-modulating effects. Human evidence is weak.
• Anticancer: A 2020 in vitro study showed shilajit inhibited breast cancer cell proliferation; 2021 data suggested bladder cancer effects. No human trials.
• Antiviral: A 2015 in vitro study noted humic acid’s activity against herpes viruses; 2020 data suggested HIV/COVID-19 inhibition. Clinical data are absent.

Benefits for diabetes, arthritis, or stress rely on animal or anecdotal data.

Clinical Evidence

Evidence is moderate for fertility and testosterone, limited for other claims:

• Fertility/Testosterone: RCTs (e.g., 2016, 2009) confirm spermatogenic and androgenic effects at 250–500 mg/day over 90 days.
• Fatigue/Muscle: A 2019 RCT supports muscle strength retention at 500 mg/day over 8 weeks.
• Bone Health: A 2022 RCT shows bone density improvements at 500 mg/day over 11 months.
• Other Areas: Cognitive, antiviral, anticancer, and altitude sickness benefits lack human RCTs, relying on preclinical or observational data. Variability in shilajit composition (e.g., fulvic acid content) and study quality (e.g., small samples, manufacturer funding) limit reliability.

Larger, independent RCTs are needed to confirm broader efficacy.

Side Effects and Safety

Purified shilajit is possibly safe at recommended doses, but risks exist:

• Common: Mild gastrointestinal upset (nausea, diarrhea) at >500 mg/day, especially without food. Bitter taste may cause discomfort.
• Rare: Allergic reactions (rash, itching) in those sensitive to humic substances. Case reports link unpurified shilajit to lead poisoning.
• Specific Risks:
  • Heavy Metal Contamination: Raw shilajit may contain lead, arsenic, or thallium; a 2025 study found some supplements had higher thallium than raw forms. Third-party testing (e.g., USP, NSF) is critical.
  • Hypoglycemia: May lower blood sugar, risking hypoglycemia with diabetes medications.
  • Iron Overload: High iron content may exacerbate hemochromatosis.
  • Hormonal Effects: Testosterone increases may affect hormone-sensitive conditions (e.g., prostate cancer).
• Contraindications:
  • Pregnancy/Breastfeeding: Avoid due to insufficient safety data.
  • Hemochromatosis: Avoid due to iron content.
  • Surgery: Stop 2 weeks prior due to blood sugar effects.
  • Children: Not recommended; no pediatric data.
• Usage Guidelines: Use purified shilajit (250–500 mg/day) with food to minimize gastrointestinal issues. Limit to 8–12 weeks for specific benefits. Monitor for allergies or hypoglycemia. Choose products with COA for heavy metal safety.

Toxicological studies show oral LD50 >2,000 mg/kg, with no systemic toxicity at 200–1,000 mg/day in humans.

Dosage and Administration

• Culinary Use: Dissolve 100–250 mg resin in warm milk, water, or tea, traditionally consumed 1–2 times daily. Provides minimal bioactives but safe.
• Medicinal Use:
  • Resin/Powder: 250–500 mg/day (1–2 doses), dissolved in liquid or taken with food.
  • Capsules: 250–500 mg/day, standardized to 5–20% fulvic acid.
  • Extracts: 0.5–1 ml (1:2 in water), 1–2 times daily.
• Timing: Morning or post-meal dosing minimizes gastrointestinal upset; benefits (e.g., testosterone, bone health) appear over 8–12 weeks.
• Storage: Store in cool, dry, airtight containers; refrigerate resin (use within 6–12 months).

Practical Applications

• Culinary:
  • Drinks: Dissolve 100–250 mg resin in herbal tea, smoothies, or warm milk for energy and mineral support.
  • Recipes: Add trace powder to soups or desserts, masking taste with honey or spices.
• Medicinal:
  • Supplements: Capsules or resin for fertility, testosterone, or fatigue, often paired with ashwagandha (consult doctor for interactions).
  • Topical: Rare, but used in Iran for bone healing (no clinical data).
• Health Goals:
  • Fertility/Testosterone: Supports male reproductive health with consistent use (250–500 mg/day).
  • Energy/Fatigue: Enhances mitochondrial function for active individuals.
  • Bone Health: Aids postmenopausal women or bone repair (500 mg/day).
• Considerations: Consult a doctor for diabetes, heart conditions, or medications. Choose purified, third-party-tested products (e.g., PrimaVie). Avoid raw shilajit due to contamination risks.

Recent X posts (as of June 5, 2025, 5:30 PM PST) praise shilajit for energy, libido, and testosterone at 250–500 mg/day, with users noting improved focus and sleep when taken before bed. Some report digestive upset or no effects, emphasizing quality (e.g., Himalayan resin over powders). Concerns about heavy metals persist, with users favoring lab-tested brands.

Current Research and Future Directions

Shilajit research is growing but limited by variability and small trials:

• Larger RCTs: Needed for cognitive, antiviral, anticancer, and altitude sickness benefits, using standardized formulations (e.g., 10–20% fulvic acid).
• Bioavailability: Exploring liposomal or nano-delivery to enhance DBPs and fulvic acid absorption.
• Safety: Long-term studies on heavy metal risks and high doses (>1,000 mg/day).
• Mechanisms: Clarifying fulvic acid’s role in tau inhibition and DBP’s mitochondrial effects.
• New Applications: Investigating synergies with adaptogens, bone regeneration, or neurodegenerative therapies.

Conclusion

Shilajit, a Himalayan phytocomplex, is a revered Ayurvedic rasayana with moderate evidence for male fertility, testosterone, fatigue reduction, and bone health, driven by fulvic acid, DBPs, and minerals. Safe at 250–500 mg/day when purified, it poses risks of heavy metal contamination in raw forms, with mild side effects like gastrointestinal upset. Its applications span energy, reproductive health, and potential cognitive support, blending 5,000 years of tradition with emerging science. However, variability in composition and limited human trials demand caution and further research. Consumers should prioritize third-party-tested products and consult healthcare providers, favoring shilajit’s promise as a supplement while awaiting robust validation.

References

1. Pandit S, et al. (2016). Clinical evaluation of purified shilajit on testosterone levels in healthy volunteers. Andrologia, 48(5), 570–575.
2. Keller JL, et al. (2019). The effects of shilajit supplementation on fatigue-induced decreases in muscular strength and serum hydroxyproline levels. J Int Soc Sports Nutr, 16(1), 3.
3. Pingali U, et al. (2022). Shilajit extract reduces oxidative stress, inflammation, and bone loss to dose-dependently preserve bone mineral density in postmenopausal women with osteopenia. Phytomedicine, 105, 154334.
4. Carrasco-Gallardo, C., et al. (2012). Shilajit: A natural phytocomplex with potential procognitive activity. PMC.
5. Ali, S. M., et al. (2024). Systematic review of Shilajit: Clinical efficacy and safety. JPTCP, 31(6), 1464–1471.