Shilajit is a tar-like resin from mountain rocks, used in Ayurveda as a rasayana, a rejuvenating tonic. It's rich in fulvic acid and minerals. Human evidence is thin: one small trial in middle-aged men reported higher testosterone (the main male sex hormone), and a few others are small and often industry-linked. The bigger issue is safety: raw or poorly purified shilajit can contain heavy metals, fungal toxins and microbes, and testing of commercial products has found contamination. If you try it, only use purified, third-party tested products, and talk to your doctor first.
- SymptomLow energy, low drive, feeling older
- Before thatClaimed: poor mineral and energy supply to cells
- Before thatClaimed: fulvic acid helps deliver nutrients and energy
- RootUnproven in humans, while contamination risk is real
What shilajit is
Shilajit is a sticky, dark resin that oozes from rocks in high mountains like the Himalayas, especially in summer heat. It forms over centuries as plant material breaks down and mixes with minerals. In Ayurveda it's a prized rasayana, a rejuvenating tonic, traditionally used for strength, stamina and vitality.
Its main active ingredient is said to be fulvic acid, a compound formed during the slow breakdown of plants in soil, along with dozens of minerals.
The claims vs the evidence
Following the marketing upstream: shilajit is claimed to improve energy production in cells, help absorb minerals and boost testosterone. Most of this comes from lab and animal studies. In humans:
Testosterone in middle-aged men
A · One small trialIn one randomized trial, where men were assigned by chance to shilajit or a dummy pill, healthy men aged 45 to 55 taking purified shilajit for 90 days had higher testosterone levels than those on a placebo, a dummy pill.[1] It tested one company's branded extract, it hasn't been independently replicated, and much of the testosterone claim rests on this single study.
Fatigue, energy, aging
C · Mostly animalSmall and animal studies only. No good human evidence for anti-aging effects.
The real concern: what's in it
Because shilajit comes straight out of rock, it can carry whatever the rock and environment contain. Raw or poorly processed shilajit can include heavy metals such as lead, arsenic and mercury, fungal toxins and bacteria. Purification is supposed to remove these, but quality varies widely, and product testing has found contamination even in some purified supplements.
This echoes a broader finding in Ayurvedic products: in a US study, about one in five Ayurvedic medicines bought online contained lead, mercury or arsenic.[2]
Shilajit is a pure mountain superfood that boosts energy and testosterone.
Human evidence is one small testosterone trial and little else. Contamination with heavy metals is a documented risk.
Who should avoid it
- Anyone pregnant or breastfeeding.
- People with gout or high uric acid, or with conditions involving too much iron.
- People with hormone-sensitive conditions.
- Anyone taking medication, until they've checked with a doctor or pharmacist.
The bottom line
Shilajit has a long tradition and a booming market, but very little human evidence and a real contamination problem. If you're after energy, the upstream causes with proven fixes, like poor sleep, low fitness, low iron or B12, are covered in why you're always tired after 40. If you still want to try shilajit, choose purified, independently lab-tested products, and talk to your doctor first.
Frequently asked questions
What are the proven benefits of shilajit?
None are firmly proven. One small randomized trial in middle-aged men reported increased testosterone after 90 days, and some small studies suggest effects on fatigue, but they're limited and not independently replicated.
Is shilajit safe?
Purified, tested shilajit appears generally well tolerated in short studies. Raw or unprocessed shilajit can contain heavy metals, fungal toxins and bacteria. Avoid it if pregnant, breastfeeding, or if you have gout, high iron or a medical condition, unless your doctor approves.
What is fulvic acid?
Fulvic acid is a natural compound formed when plant matter breaks down in soil over long periods. It's claimed to help the body absorb minerals, but evidence in humans is very limited.
How can I tell if shilajit is genuine and clean?
You can't tell by looking. Choose products with a certificate of analysis from an independent lab showing tests for heavy metals and microbes. Be wary of very cheap resin sold online.
Sources
- Pandit S, et al. Clinical evaluation of purified Shilajit on testosterone levels in healthy volunteers. Andrologia, 2016.
- Saper RB, et al. Lead, mercury, and arsenic in US- and Indian-manufactured Ayurvedic medicines sold via the Internet. JAMA, 2008.