Shilajit, Fulvic Acid, and Testosterone: Sorting Fact from Hype
Not all that glitters is gold.
Walk into any supplement aisle today, and you will see dozens of glossy jars promising the “power of the Himalayas” in a resin called Shilajit. Brands aggressively market it as a natural testosterone booster and a gut nutrient absorber, thanks to its supposed high content of fulvic acid. Instagram is bombarded with reels of bodybuilders promoting various brands of Shilajit and claiming that it improves their performance. Bollywood actors like Tiger Shroff, who has even promoted a pan masala brand (in a surrogate advertisement), have also endorsed these brands. But how much of this is science, and how much is marketing? Let’s look closely at what the research actually says.
What is Shilajit?
Shilajit is a sticky tar-like substance formed from the slow decomposition of plant material trapped in Himalayan rocks over centuries. Chemically, it is a complex mixture of fulvic acids, humic substances, dibenzo-α-pyrones, and trace minerals. Fulvic acid is often highlighted because it can form complexes with minerals and has antioxidant properties. Supplement companies have taken that fact and stretched it into claims of “nutrient absorption” and “testosterone boosting.”
Evidence for testosterone boost
The strongest scientific claims about Shilajit come from two studies.
A study enrolled 96 men, of whom 75 completed the trial. Participants took 250 mg of purified Shilajit twice daily for 90 days. Results showed a ~20% increase in total testosterone and a ~19% increase in free testosterone compared with placebo.
Another trial studied 35 infertile men, 28 of whom completed the protocol. Participants received 100 mg Shilajit twice daily for 90 days. Researchers reported improvements in semen quality and a ~23% increase in serum testosterone compared with baseline.
At first glance, these findings look encouraging. But there’s a catch: both studies were conducted by Ayurveda doctors, and the sponsoring institutions have close ties to the Ayurvedic industry. Ayurveda as a whole has long been criticized for lack of robust evidence, inconsistent standardization, and safety concerns. So while the results are interesting, they come from within a system that itself has not met modern scientific standards of proof.
Fulvic acid: guilty by association?
Here’s the critical nuance: the testosterone effect is observed with whole Shilajit, not with isolated fulvic acid. Fulvic acid on its own has not been shown in human studies to increase testosterone. Reviews describe it as an antioxidant and chelating agent, but claims of hormonal activity remain unproven. Marketing that labels fulvic acid as a “testosterone booster” is misleading, it is Shilajit, with its mix of multiple bioactive compounds, that shows some signal in trials.
Another frequently repeated claim is that fulvic acid “enhances absorption of nutrients from the gut.” There is some in vitro and animal model evidence that fulvic acids can bind minerals, potentially altering absorption. But in human studies, the proof is thin.
A randomized, controlled trial of oral humic acids in patients with irritable bowel syndrome with diarrhea found no significant benefit over placebo (Haufe et al., 2021). The study did not measure nutrient absorption directly. In short, the idea is biologically plausible, but we lack convincing clinical data.
Safety and Money
Not all Shilajit is created equal. Raw or unpurified Shilajit may contain toxic levels of heavy metals such as lead, arsenic, or mercury. In 2021, both the U.S. FDA and Health Canada issued public warnings and recalls of fulvic acid products due to unsafe heavy metal contamination. These were not fringe advisories; they were nationwide alerts after testing confirmed elevated levels of heavy metals.
And here’s another reality check: a small pack of branded Shilajit costs about ₹1000 in India. That same money could easily buy a decent supply of protein supplement or contribute to a gym membership, both of which have far stronger, proven effects on muscle growth, fitness, and overall well-being. Shilajit, by comparison, offers only modest, uncertain benefits.
For most Indians chasing a “fit, filmy six-pack body,” these supplements are just marketing gimmicks feeding off desperation. If health and fitness are the goals, a disciplined exercise routine and adequate protein intake will get you far more results than a jar of resin.
References
Pandit S, Chauhan NS, Dixit VK. Effect of Shilajit on testosterone levels in healthy volunteers. Andrologia. 2016;48(9):928–934. PubMed
Sharma P, Joshi T, Joshi A, et al. Clinical evaluation of purified Shilajit in oligospermia. Andrologia. 2010;42(1):48–56. PubMed
Haufe S, Gammel G, Schiefke I. Humic acids in patients with diarrhoea-predominant irritable bowel syndrome: results from a randomised controlled trial. Biomedical Journal of Scientific & Technical Research. 2021;33(1):25584–25591. PDF
Carrasco-Gallardo C, Guzmán L, Maccioni RB. Shilajit: a natural phytocomplex with potential procognitive activity. Int J Alzheimers Dis. 2012. PubMed | Full text
U.S. Food and Drug Administration. FDA advises consumers not to use fulvic care powder and tablets from Black Oxygen Organics due to elevated levels of lead and arsenic. 2021. FDA advisory
Health Canada. BlackOxygen Organics recalls fulvic acid tablets and powder due to potential health risks. 2021. Health Canada recall