Shilajit and ashwagandha are different things. Shilajit is a blackish-brown exudate collected from high mountain rock, made up mostly of humic substances such as fulvic acid. Ashwagandha is the root of Withania somnifera, a shrub of the drier parts of India, characterised by steroidal lactones called withanolides. No human trial has compared the two. If you are thinking of taking either for a health reason, or take any medicine, follow your doctor's advice.
At a glance
- A 2012 review in the International Journal of Alzheimer's Disease describes shilajit as an exudate from high mountain rocks in which humic substances make up around 60 to 80 per cent of the material.
- A 2009 review in Molecules describes Withania somnifera as an undershrub 30 to 75 cm high with long tuberous roots, with more than 40 withanolides reported from the genus.
- The shilajit trials we found are small and short: a 2010 study in Andrologia enrolled 35 men for 90 days; a 2019 trial in the Journal of the International Society of Sports Nutrition had 63 men for 8 weeks.
- A 2025 meta-analysis in BJPsych Open pooled 14 ashwagandha trials, 360 people treated and 353 controls, lasting 6 to 12 weeks, and rated the certainty of the evidence low or very low.
- A 2020 case series in Liver International reports five cases of liver injury attributed to ashwagandha supplements, starting 2 to 12 weeks after first use.
What is shilajit and what is ashwagandha?
Shilajit is a substance that seeps from rock at high altitude, a mixture of decomposed organic matter and minerals with no single origin species. Ashwagandha is a single cultivated species, Withania somnifera, and the part used is its root.
The 2012 review by Carrasco-Gallardo and colleagues describes shilajit as "a blackish-brown powder or an exudate from high mountain rocks", found mainly in the Himalayas and also reported from Russia, Tibet, Afghanistan and northern Chile. It is thought to form through the decomposition of plant material, and its composition varies by region.
Ashwagandha, in the 2009 review by Mirjalili and colleagues, is "an erect, grayish, stellate-tomentose undershrub (30-75 cm high) with long tuberous roots", of the family Solanaceae, widely cultivated in the drier parts of India. Its roots' reputation as a restorative earned them the name "Indian ginseng". A 2025 meta-analysis in BJPsych Open notes it is sold today as capsules, tablets and powders.
How is each traditionally prepared and taken?
Shilajit is purified before use; ashwagandha root is dried and goes into formulations. Neither review describes a home method. Preparation matters more for shilajit, whose raw material carries contaminants.
On shilajit, the 2012 review is blunt: "a purified, ready-for-use preparation for human consumption must be used", because unpurified material may contain mycotoxins, heavy metal ions, polymeric quinones and free radicals. The trials below used "processed" or "purified" shilajit, two of them in capsules. What a purified product should look like is in our guide on how to identify pure shilajit.
On ashwagandha, the 2009 review says the roots have been used in Ayurvedic and indigenous medicine for over 3,000 years as a restorative, and are a component of over 200 formulations in Ayurvedic, Siddha and Unani medicine. The trials pooled in 2025 used root extracts whose composition, the meta-analysis notes, was inconsistently reported.
What compounds characterise each?
Shilajit is characterised by humic substances, above all fulvic acid; ashwagandha by withanolides, a family of steroidal lactones. The two have no chemistry in common.
The 2012 review puts humic substances at around 60 to 80 per cent of shilajit. Fulvic acid is the smallest fraction, about 2 kilodaltons against 5 to 10 for humic acid, and the review names it the biologically active component, along with dibenzo-alpha-pyrones, which it describes as carriers of other substances. How fulvic acid is defined and measured is covered in fulvic acid explained.
Withanolides, in the 2009 review, are "C28-steroidal lactone triterpenoids built on an intact or rearranged ergostane framework". More than 40 have been reported from Withania species; the best known are withaferin A and withanolide A. One detail cuts against the marketing: the review says withanolides are "mainly localized in leaves", and in the Indian chemotype it cites, withaferin A was absent from the roots, the part actually used.
What human trials exist for shilajit?
Very few, all small, none longer than 90 days. The 2012 review itself says shilajit "lacks systematic documentation and well-established clinical trials". We opened three: two from the same Ayurvedic college in Kolkata, the third funded by a supplement manufacturer.
- Biswas and colleagues (2010), Andrologia: 35 men with low sperm counts were enrolled and 28 completed 90 days of processed shilajit capsules. Semen measures improved against their own baseline; the abstract mentions no placebo group.
- Pandit and colleagues (2016), Andrologia: a randomised, double-blind, placebo-controlled study in healthy men aged 45 to 55, run for 90 days. The abstract reports higher total testosterone, free testosterone and DHEAS than placebo, and does not give the number of participants.
- Keller and colleagues (2019), Journal of the International Society of Sports Nutrition: 63 recreationally active men, mean age about 21, in three groups for 8 weeks. The only difference across the whole group was a smaller fatigue-induced fall in strength in the higher-dose group than in the lower-dose group. No adverse events were reported. The trial was funded by Natreon Inc., which supplied the capsules.
What human trials exist for ashwagandha?
More than for shilajit, but still small and short. A 2014 systematic review found five trials; a 2025 meta-analysis found fourteen, with 713 participants. Both centre on anxiety, and both warn of bias and inconsistency.
The 2014 review by Pratte and colleagues found five randomised trials of 39 to 130 participants, lasting 6 to 12 weeks, all measuring patient-reported anxiety or stress. Four of the five favoured ashwagandha, but "none of the studies attained a low risk-of-bias rating according to Cochrane criteria", and none reported significant adverse effects.
The 2025 meta-analysis by Marchi and colleagues pooled 14 trials in people with mental disorders, mostly anxiety disorders: 360 treated and 353 controls, median length 8 weeks. It found evidence supporting an effect on anxiety symptoms, but heterogeneity was very high, one outlying trial strongly influenced the result, and certainty was graded low for anxiety, sleep and stress and very low for depression. On safety it found no difference from comparators in dropouts or adverse events; the most common were transient gastrointestinal effects.
Have shilajit and ashwagandha been compared head to head?
No. We searched PubMed for both names together and got ten papers, none of them a human trial comparing the two. The studies that test both are animal studies, such as a 2016 mouse study and a 1997 rat-brain study, or tests of multi-herb formulations containing both. Any page that ranks one above the other is giving an opinion, not reporting a result.
What are the safety concerns with each?
The concerns differ in kind. For shilajit, the documented risk is contamination of the raw material, which purification and batch testing address. For ashwagandha, it is the substance itself: case series from three countries describe liver injury in people taking ashwagandha products.
| Shilajit | Ashwagandha | |
|---|---|---|
| Source | Exudate from high mountain rock, mainly Himalayan | Root of Withania somnifera, a shrub cultivated in the drier parts of India |
| Form | Purified resin or powder; capsules in trials | Dried root in formulations; root extract in capsules, tablets and powders |
| Characterising compounds | Humic substances (about 60 to 80 per cent), chiefly fulvic acid | Withanolides, more than 40 known |
| Human trials found | Three: 35 men for 90 days; an RCT of unstated size for 90 days; 63 men for 8 weeks | Five trials of 39 to 130 people (2014 review); 14 trials, 713 people, 6 to 12 weeks (2025 meta-analysis) |
| Safety notes | Unpurified material may carry mycotoxins, heavy metal ions, polymeric quinones and free radicals | Liver injury case series: five cases in Iceland and the US (2020); 23 patients in India, three deaths (2023) |
The 2012 shilajit review also cites a study finding that Ayurvedic products sold online "may contain detectable heavy metals levels as lead, mercury, and arsenic". See shilajit heavy metal testing and shilajit safety and interactions.
For ashwagandha, the 2020 case series by Björnsson and colleagues in Liver International describes five people in Iceland and the United States aged 21 to 62. Symptoms began 2 to 12 weeks after they started an ashwagandha supplement; every patient had jaundice, none developed liver failure, and liver tests returned to normal within one to five months in four of them. The authors conclude that "these cases illustrate the hepatotoxic potential of ashwagandha".
The 2023 series by Philips and colleagues in Hepatology Communications is larger and worse: 23 patients across Indian centres between January 2019 and December 2022, with the eight who took a single-ingredient product reported in detail. Three presented with acute-on-chronic liver failure and all three died, and chemical analysis "revealed only natural phytochemicals without adulteration or contamination".
Case reports cannot say how often this happens, only that it does. If you take ashwagandha and develop jaundice or itching, stop and see a doctor.
The short version
Shilajit is a purified rock exudate made mostly of humic substances; ashwagandha is a plant root characterised by withanolides. No human trial has compared them. The shilajit evidence is three small trials of up to 90 days. The ashwagandha evidence is 14 trials of 6 to 12 weeks graded low or very low certainty, plus case series of liver injury from three countries. Follow your doctor's advice before taking either.
Sources
Further reading behind the figures above. Himdhara's own numbers — yields, batch results — come from our production records and the batch reports on the lab reports page.
- Carrasco-Gallardo C, Guzmán L, Maccioni RB (2012). Shilajit: A Natural Phytocomplex with Potential Procognitive Activity. International Journal of Alzheimer's Disease.
- Mirjalili MH, Moyano E, Bonfill M, Cusido RM, Palazón J (2009). Steroidal Lactones from Withania somnifera, an Ancient Plant for Novel Medicine. Molecules.
- Pandit S, Biswas S, Jana U, De RK, Mukhopadhyay SC, Biswas TK (2016). Clinical evaluation of purified Shilajit on testosterone levels in healthy volunteers. Andrologia.
- Marchi M, Grenzi P, Travascio A, Uberti D, De Micheli E, Quartaroli F, Laquatra G, Pingani L, Ferrari S, Galeazzi GM (2025). The effect of Withania somnifera (Ashwagandha) on mental health symptoms in individuals with mental disorders: systematic review and meta-analysis. BJPsych Open.
- Björnsson HK, Björnsson ES, Avula B, Khan IA, Jonasson JG, Ghabril M, Hayashi PH, Navarro V (2020). Liver Injury due to Ashwagandha. A Case Series from Iceland and the U.S. Drug-Induced Liver Injury Network. Liver International.