But does it actually work? History certainly makes a compelling case, as does some compelling research. While this is all encouraging, it still doesn’t mean that bentonite clay delivers on every one of its head-to-toe, health-boosting claims or that it’s safe to consume. So we dove into the research to help set the record straight. Bentonite clay is part of the “smectite” group of clay that’s known for an ability to expand when exposed to a liquid. It’s rich in minerals, including silica, magnesium, calcium, sodium, copper, iron, and potassium. There are two types of bentonite clay, depending on the ratio of key minerals they contain: sodium bentonite clay and calcium bentonite clay. They have similar properties, with subtle nuances. “Both kinds can be used for facial masking,” says Samantha Story of Studio Britta, a holistic skin care clinic in NYC. “Sodium bentonite draws more toxins out of the skin, and calcium bentonite is gentler and provides the skin with more minerals. While both types have their benefits, I prefer calcium bentonite for facial masks or using a mixture of the two for more congested skin.” Calcium bentonite clay, particularly green calcium bentonite clay, is also the type that’s typically preferred for consumption (in small amounts, of course) when used for detoxification purposes, as it seems to be a bit gentler on the body. While it may be relatively new to you, there’s evidence that some of the earliest civilizations used clay to treat everything from aches and pains to infections and food poisoning. In ancient Mesopotamia1 (5000 to 3500 BCE), for instance, it’s believed that people used a number of natural substances, including clays, to make poultices—mixtures of clay and water (or other wet ingredients like tea) wrapped in thin cloth and applied to the body to relieve pain and inflammation. While human clinical trials are scarce, a few do exist, along with some impressive lab and animal research. It’s important to note, however, that many of these findings need to be validated before they can become true recommendations. That said, here are some of the most promising potential benefits of bentonite clay to date: Some animal research does seem to support this. Bentonite clay could help bind aflatoxins in the body when ingested and reduce their toxicity, according to several animal feeding studies. If you’re not familiar, aflatoxins are a family of cancer-causing toxins produced by fungi found on agricultural crops such as corn, peanuts, cottonseed, and tree nuts. People can be exposed by eating contaminated crops, and research shows that aflatoxin exposure is associated with an increased risk of liver cancer. In one study3, adding bentonite clay to aflatoxin-contaminated corn partially restored pigs’ liver function, and it did not impair their absorption of other minerals, and in another4, rabbits eating an aflatoxin-contaminated diet experienced an improvement in reproductive function once their feed was supplemented with bentonite. Bentonite may hold promise for countering the negative effects of heavy metals, too. Heavy metals like arsenic, cadmium, lead, and mercury can wreak havoc on our bodies, leading to everything from exhaustion to serious diseases. Too much cadmium, for example, has been linked to kidney disease, osteoporosis, and cardiovascular disease. But in one study5, feeding pigs montmorillonite clay (the same as bentonite clay) for 100 days reduced the concentration of lead in their blood, brain, liver, bone, kidneys, and hair. Similar findings6 were made with carp, too—exposing them to cadmium caused oxidative stress, but supplementing their diet with clay reversed oxidative damage to the liver and kidneys. Of course, humans aren’t animals, but the fact that bentonite clay has similar toxin-removing effects among various species—without compromising the absorption of other minerals—is certainly intriguing. In particular, bentonite clay may hold promise for people suffering from irritable bowel syndrome (IBS). In one small clinical trial7, patients with constipation-predominant IBS who took 3 grams (a bit less than a teaspoon) of bentonite clay twice a day for eight weeks experienced improvements in bowel movements compared to a placebo group. No reduction in pain was noted, however. It’s not clear why exactly bentonite exerts positive effects on the digestive system, but some speculate that a reduction in IBS may be due to improvements in the health of the gut lining. There’s also some evidence in animals that bentonite clay has anti-parasitic properties8, which could potentially ease stomach woes. Benefits, like heartburn relief, have more obvious explanations—the minerals in bentonite clay, including calcium and magnesium, have acid-neutralizing properties. All that said, however, there’s still no clear consensus on whether we should actually be consuming bentonite clay. Scientists at Arizona State University wanted to test out the antibacterial potential of smectite clay minerals10 (a group that encompasses bentonite clay) on a variety of bacteria that were both resistant and nonresistant to antibiotics. When they exposed this bacteria to the clay minerals in the lab, the clay exhibited antibacterial properties that were effective at killing MRSA, various types of E. coli, and Salmonella. While the researchers haven’t pinpointed the mechanism by which clay kills bacteria, they do believe it holds promise for the development of treatments to fight antibiotic-resistant infections. In one study, a lotion containing bentonite clay was shown to be effective at preventing or reducing the severity of poison ivy11 when applied to skin before coming into contact with poison ivy’s itch-inducing compound urushiol. The same lotion featuring bentonite effectively treated chronic dermatitis12 (irritated and inflamed skin, like eczema). Bentonite holds promise as a diaper rash treatment, too—one study found that a bentonite diaper cream acted better and faster than a calendula diaper cream13. Within the first six hours, 88 percent of the skin lesions in the bentonite group started improving, while only 54 percent started improving in the calendula group. The reasons for these benefits aren’t exactly clear, but they may have to do with the fact that bentonite clay particles form a physical barrier that protects the skin or that clay can absorb a significant amount of water and be an effective way of drawing out skin-irritating substances. The minerals in bentonite clay may also have skin-soothing properties. But in addition to removing dirt, excess oil, and other skin saboteurs, bentonite may work its magic on your mug in another way—by boosting collagen production. In a small animal study, a daily application of bentonite clay to the skin increased the number of collagen fibers14 after just seven days. This may be due to bentonite’s high levels of the mineral silica, which helps maintain healthy connective tissue. While this collagen-boosting benefit hasn’t been established in humans, it’s certainly promising enough to consider a bentonite face mask. Bentonite seems to have potent skin-clarifying benefits, too. A study on men and women with mild acne found that a mask of jojoba oil and bentonite clay—applied two or three times a week for six weeks—was effective at reducing the number of acne lesions15 by an average of 54 percent. Bentonite may even improve the look and feel of your hair. Countless natural beauty bloggers swear by bentonite clay hair masks, as the clay supposedly moisturizes and draws out excess dirt and oil simultaneously. While there haven’t been studies on this, bentonite clay is used in various parts of the world16 to cleanse and soften hair. Another pro tip: While bentonite clay is sold as a powder, you may want to keep a jar of paste on hand, since several of the uses below call for a paste. According to Redmond Clay, you can do this by combining 1 part bentonite clay with 2 parts water in a Mason jar and mixing or shaking well. Now, here are some of our favorite bentonite clay uses for health and beauty: “As bentonite clay draws out heavy metals, it frees up the lymphatic system, a key component to good health,” says Story. “We have lymph nodes in our armpits as well as detoxifying sweat glands, making this a great place to aid lymphatic drainage by doing an underarm mask. If you’re considering switching to natural deodorants I recommend this mask to aid in the transition as it helps restore a healthy pH and a more pleasant odor.” Additionally, the lead present in bentonite clay is bonded to other molecules, which means it may actually be safer than the isolated forms of lead you’d find in lead paint or contaminated cosmetics. One brand describes it this way: “The lead atoms in bentonite clay are so tightly bound in a matrix with other atoms that they do not break away from this matrix as the clay travels through your body or interacts with your skin. In fact, these clay molecules have an unusually large surface area with such a strong negative charge, they act like a strong magnet to draw the positively charged lead out of your body.” While that claim may sound self-promotional, animal research does seem to support it. Remember the pig study5 mentioned above? It found that feeding the pigs montmorillonite clay (the same as bentonite clay) for 100 days reduced the concentration of lead in their blood, brain, liver, bone, kidneys, and hair. Even so, there have still been some scares—in 2016, the U.S. Food & Drug Administration warned consumers17 not to purchase the small brand Best Bentonite Clay due to elevated lead levels. This means it’s extremely important to purchase a clay sold by a reputable brand that has ideally done an elemental analysis of their product to ensure safe lead levels (if you don’t see one on their website, you can request one).
