Mention the word "clay" and you may think of making pottery—or applying a face mask as part of a beauty treatment. Though you may never have considered actually eating the dirt, devotees claim it's actually beneficial to your health, providing energy and eradicating a multitude of woes.

"Clay is the best detoxifier in the world," says Ran Knishinsky, author of The Clay Cure: Natural Healing from the Earth. "When taken internally, clay attracts toxins in the body and gets rid of them."

Knishinsky, owner of a homeopathic dispensary and health food store in Phoenix, Arizona, has been eating clay every day for 20 years. He purports that, besides keeping him regular, it gives him increased energy. He first became aware of clay when he developed a ganglion cyst on his wrist two decades ago.

Surgery is the recommended course of treatment, and Knishinsky hoped to avoid it. So he visited a local health food store, where the owner told him that he believed the cyst was due to a buildup of poisons that had become concentrated in the wrist joint. The owner recommended he try eating clay, which he did. Within two months, the cyst was gone. Knishinksy says he's been consuming clay ever since.

The consumption of clay is nothing new. More than 200 cultures worldwide eat clay, Knishinsky says. As a medicinal, it's been in use for thousands of years. "Clay has always been touted as a cure for intestinal ailments," Knishinsky says. "Mahatma Gandhi recommended it to overcome constipation."

The History of Clay Eating

Geophagy (or the consumption of soil) was practiced as far back at 300 BC, as was documented by Aristotle. It has been prescribed to cure a variety of illnesses and to counteract poisons, and cooks in some countries even mixed it into bread dough. 

Since clay is rich in minerals, it makes it an especially attractive dietary supplement, says Knishinsky. The body can't manufacture minerals on its own, and consuming the appropriate clay can help ensure you get enough calcium, iodine, iron, magnesium, and phosphorus, among others, he explains.

However, he's not talking about heading out to the backyard and harvesting what you find there. While there are seven groups of clay, most of the research on edible clay has been done on montmorillonite, Knishinsky says. Its minerals are fine-grained and thin-layered, and it has the ability to absorb toxins in greater amounts than other clays.  

After just two to four weeks of eating clay, according to Knishinsky, you can expect better digestion, more alertness and clear-headedness, higher resistance to infections, clearer skin, and a surge in physical energy.

Not everyone agrees that it makes sense to eat clay.

"It is not something I would recommend," says Andrea N. Giancoli, MPH, RD, a spokesperson for the Academy of Nutrition and Dietetics. Aside from the fact that it is not strictly regulated by the federal government, she says it can cause constipation due to its binding effect.

"And since it has this effect, it can bind nutrients like iron and zinc and prevent your body from absorbing them," she adds.

Still, Knishinsky, promotes eating clay for good health. But, he stresses, clay should be taken over a long period of time in order to see results. "It's not an instant cure for whatever ailments you might have, but when taken over the long haul, you'll see positive results," he says.

Not sure how to find clay—or if it's safe? Health food stores carry edible clay, Knishinsky says. It's available for consumption in capsules, tablets, powder, and hydrated gels. Additionally, he cautions that clay should be consumed on an empty stomach.

Andrea Giancoli, MPH, RD, reviewed this article.



Ran Knishinsky, author of The Clay Cure: Natural Healing from the Earth (Healing Arts Press)

Eckholm, Erik. 22 July 1986. "Clay eating proves widespread but reason is uncertain." The New York Times.