Sea moss is the latest online wellness supplement craze.

Bella Hadid showed off an extensive morning "wellness" routine that included drinking a glass of sea moss gel. Model Winnie Harlow just launched a signature smoothie featuring "nutrient-rich sea moss" at trendy Los Angeles-based supermarket Erehwon. Kourtney Kardashian's vitamin brand Lemme offers cute lavender-colored bottles of sea moss liquid drops. TikTok influencers are trying to sell viewers sea moss gummies via TikTok Shop, promising they'll get a slew of health benefits.

Do they actually, though? Here's what nutrition experts want you to know about sea moss before trying it.

What is sea moss good for?

Sea moss is a type of seaweed that's often used as a supplement in gel, liquid, capsule or gummy forms. It's seen by many as healthy because it contains some vitamins, minerals and phytochemicals that "may have some health benefits in certain quantities," registered dietitian Miranda Galati tells USA TODAY.

"But I'm not convinced it's any better for you than your everyday fruits and vegetables, which have much more research to back their health claims," Galati adds. "Unfortunately the health claims behind sea moss are mostly unsupported."

While fans of sea moss say it can offer benefits including for digestion, thyroid health and immunity, "the research simply doesn't support it," Galati notes. In previous years, the Food and Drug Administration (FDA) has designated certain brands of sea moss as "unapproved" because of false claims about the product being able to "diagnose, cure, mitigate, treat or prevent disease.”

Medicines must be approved by the FDA before they can be sold, but dietary supplements (including sea moss) don't require the same level of scrutiny, according to the National Institutes of Health (NIH) Office of Dietary Supplements. Supplement companies need to have evidence that their product claims aren't misleading but they don't need to provide that evidence to the FDA before they're able to put the product on the market.

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Is it safe to take sea moss every day?

Taking sea moss can put users at risk of iodine toxicity, digestive issues and heavy metal poisoning, Galati says.

Types of sea algae, including seaweed and sea moss, are sometimes prone to accumulate heavy metals, according to the Ohio Department of Agriculture's Division of Food Safety. And because brands aren't required upfront to meet the same standards as medicine companies, you might be taking a sea moss supplement high in heavy metals without knowing.

Medical research on consuming sea moss is "limited and new," Galati notes. Not only does that mean experts don't know much about its actual benefits, but they also don't know a lot about the potential short- and long-term health risks it could present for users.

"It might have some potential benefits, but I don't think it's worth the risk," she adds.

Who shouldn't take sea moss?

The moral of the story is to proceed with caution when considering taking supplements like sea moss. But especially those who are pregnant, breastfeeding, over 65 or dealing with any thyroid conditions should avoid consuming any sea moss products, Galati says.

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"It's also possible that sea moss products could interact with medications, so it's important to approach with caution," she adds. "To be safe, speak with your doctor or healthcare team before adding this to your routine."