WASHINGTON -- What's the best way to detox your body? Claims are muddier than ever.
"Divergent" and "The Fault in Our Stars" actress Shailene Woodley has been in the news recently, promoting more than her two blockbusters. She's been vocal about one of her favorite things to eat: clay.
"Clay binds to other material in your body and helps your body excrete those materials that are not necessarily the best for you, like toxins and heavy metals," Woodley told David Letterman when she guest-starred on the "Late Show" in May.
Woodley spoke on the ancient practice of clay-eating around the world, and its benefits to pregnant women in particular.
But before you go digging in your backyard for a handful of dirt, Janet Helm, registered dietitian and blogger with Nutrition Unplugged, says you're better off heading to the drugstore.
"Many ancient cultures practiced clay eating -- ancient Greeks, Native Americans; it was popular in Africa," Helm says. "There are a lot of minerals in soil … soil was considered the original mineral supplement. But you can get your minerals a lot safer with a mineral supplement and prenatal vitamins."
When it comes to detoxing the body, Helm says most people's bodies do that on their own -- without the help of clay.
"We are not contaminated with heavy metals. We have our livers and our kidneys to help us detox, so there's really not an established need for that," she says.
Draining metals and minerals out of the body, as clay-eating claims to do, can lead to more problems than benefits -- such as depleting the body of iron.
Additionally, Helm says, the risks of possible contaminants, such as arsenic and lead, aren't worth the risk.
Clays, or "healing clays," are sold in natural health stores, primarily as a cosmetic mask.
Woodley told Letterman she buys her clays from online store Mountain Rose Herbs. Clays on the website run anywhere from $5 for 1 lb. of white cosmetic clay, to $225 for 50 lbs. of Fuller's Earth Clay.
Helm says if you are going to try clay-eating, it's best to not do it too frequently, since it can cause constipation.
"I'm hoping this is something people can just use cosmetically and not really jump on the bandwagon for this," Helm says. "Just because a wonderful celebrity recommends this -- I wouldn't get your nutrition advice there."
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