Do Shilajit, Other Rock Extracts Boost the Immune System?

May 27, 2013, 5:21 p.m. ET

Do Shilajit, Other Rock Extracts Boost the Immune System?

By LAURA JOHANNES

The Claim: Minerals and acids taken from rocks, including shale in the U.S. and tar from India, are good for your health. Rock ingredients vary, but can include fulvic and humic acids, and dozens of metals and minerals including iron, zinc, gold and silver, scientists say. Proponents say these ingredients soothe inflammation, boost the immune system and act as an antioxidant. A well-known rock-based treatment is shilajit, (pronounced shil-a-jeet), a tar-like substance scraped from rocks in the Himalayas.

The Verdict: “There is no known benefit of shilajit or other rock extracts” and they haven’t been adequately tested for safety in humans, says Philip J. Gregory, a pharmacist at ConsumerLab.com., which does independent testing on dietary supplements. Composition of rock-based therapies may vary from sample to sample, so it’s hard to be sure exactly what you’re getting, he adds.

Blk Enterprises’s Blk mineral-infused water sells for $2.49 for a 16.9-oz. bottle, while Pure Shilajit, a Himalaya tar-like resin which can be mixed in a liquid, sells for $380 for 90 grams.

The idea of consuming the nutrients in rocks for health benefits goes back thousands of years, says Dhaval Dhru, acting chairman of the department of Ayurvedic Sciences at Bastyr University in Kenmore, Wash. In ayurveda, or traditional Indian medicine, a small amount of shilajit is taken in warm milk, he says, to improve libido and treat a range of health problems such as diabetes and anemia.In his practice, Dr. Dhru says shilajit does appear effective, particularly in combination with lifestyle changes, but he also counsels patients to continue taking Western medicines until they are no longer needed.

Today, shilajit and other rock extracts are sold in the tar-like form directly from the rock and in powders and capsules. Costs range from under $10 for a month’s supply of capsules to more than $100 a month for the pure resin. Or you can drink some rock: Blk water, $2.49 for 16.9 ounces, includes a mineral-rich extract from domestic shale that turns the water black.

Evidence in favor of rock-based therapies is so far limited to animal and lab tests. In two lab tests paid for by Blk Enterprises LLC of Oakland, N.J., Blk water showed antioxidant activity against a number of free radicals, unstable atoms or molecules that can damage cells.

Human trials are rare. In a six-month study of 16 Alzheimer’s patients published last year, researchers at the International Center for Biomedicine in Santiago, Chile, found that patients who took a blend of shilajit and vitamins experienced fewer disease symptoms on 12-point rating scale than those taking a placebo. But those results are preliminary and no health benefits have been proven in large, well-designed human trials, scientists say.

A possible concern is that fulvic acid in polluted drinking water in China has been linked in several scientific reports to Kashin-Beck disease, a debilitating bone disorder. The reports suggest a possible connection but don’t prove that fulvic acid is the culprit.

Blk Enterprises spokesman Albie Manzo says the fulvic acid in Blk water is “completely different” than the acid in the Chinese water, and Blk water undergoes rigorous quality control so it is contaminant free. Blk is marketed as a natural way to get minerals and other nutrients, not as a medical cure-all, he adds.

Pure Shilajit of Ogonnelloe, Ireland, sells a Himalaya resin for $380 for a 90-gram supply that lasts about three months, or $490 for a premium sun-treated version. At first, it was bitter and intense, but then it left a rocklike taste in my mouth for about an hour. Blk water tasted similar to ordinary water but it tingled on my tongue.