Das 2016: shilajit and muscle gene study

This study from Ohio State University’s Wexner Medical Center looked inside muscle to see what shilajit does at the level of genes. Overweight adults took a purified shilajit extract for 8 weeks, then kept taking it for 4 more weeks while doing supervised treadmill exercise. Small muscle samples were taken at each visit and analysed for gene activity.

The researchers found that a cluster of genes involved in the scaffolding around muscle fibres, and in muscle repair, became more active. That is interesting biology. It is not evidence that shilajit improves strength, fitness or weight, none of which were the focus.

What did the Das 2016 study do?

Adults aged 21 to 70 with a body mass index (BMI) of 25 to 35, meaning overweight or class I obese, took 250 mg of PrimaVie shilajit twice a day for 8 weeks. For the next 4 weeks they continued the supplement and added supervised treadmill exercise. At the start, at 8 weeks and at 12 weeks, the researchers took blood and a 5 mm muscle biopsy, and measured gene activity across the whole genome with a microarray (Das et al., 2016).

What did it find?

After 8 weeks on shilajit, 17 probe sets for genes connected with the extracellular matrix (ECM), the network of proteins that surrounds and supports muscle fibres, were significantly more active than at the start. They included genes for collagen, elastin, fibrillin 1, fibronectin 1, decorin, tenascin XB and myoferlin, a protein involved in repairing damaged muscle fibres. The researchers confirmed these changes using a second technique, quantitative PCR.

Blood glucose, cholesterol, triglycerides, creatine kinase and myoglobin did not change after 8 weeks or after the further 4 weeks with exercise. The authors describe the supplement as well tolerated.

What does this mean?

It gives a plausible biological explanation for some of the other findings on shilajit. Later trials found that shilajit reduced a blood marker of collagen breakdown in some young men (see Keller 2019) and raised a marker of collagen production (see Neltner 2024). Turning up collagen and other ECM genes in muscle fits with both.

It also adds a little to the safety picture: 12 weeks at 500 mg a day with no reported side effects and no change in blood sugar or cholesterol.

What doesn’t it show?

• Stronger or fitter muscles. The study did not report strength, endurance or muscle size.
• Weight loss. Body weight and BMI stayed about the same, at around 188 lb and a BMI of 29.
• That shilajit caused the gene changes. With no placebo group, changes over 8 weeks could partly reflect season, diet, the biopsy process itself or chance.
• That more gene activity means more protein. Genes being switched on doesn’t always mean more of the protein is made, or that tissue works better.

How much should we trust it?

Treat it as early, mechanistic research. The lack of a control group is the biggest weakness, and the paper’s description of 16 participants against 29 enrolled in the registry is not explained in the text we read. The study was part-funded by Natreon, used its product, included one of its employees as an author, and the registry names its chief executive as sponsor. Public funding from the US National Institutes of Health also supported the work.

We count it as supporting evidence on our exercise performance page, which we grade as weak.

Where does this study fit?

This study helped prompt the later collagen and skin research. For what shilajit has been shown to do for performance, see shilajit and exercise performance; for how the 500 mg dose compares with other trials, see dosage. The full list of human trials is in the research library.