What grows in the ocean, is packed full of nutrients and, if you listen to wellness influencers, can do everything from boosting your gut health to giving you glowing skin? It's sea moss, the latest social media superfood.
Sea moss is actually a generic term used to describe different red seaweed plants that grow in the North Atlantic, particularly off the Irish coast, as well as in warmer waters such as in parts of the Carribean, says Vanessa King, a registered dietician and spokesperson for the American Academy of Dietetics.
King says you've probably eaten a sea moss product without knowing it. It's long been harvested for its carrageenan, which is used in the food industry as a thickening agent and emulsifier in products like ice cream and puddings, even nut milks.
These days, you'll also find sea moss sold as pills, powders, gummies, dried flakes and often, as an edible gel made from sea moss that has been soaked in water.
TikTok content creators and celebrities like Kim Kardashian and Hailey Bieber have embraced sea moss as part of their wellness and beauty routines.
All the buzz has translated into a global sea moss market that's projected to be worth nearly $3 billion by 2030, according to an analysis by Grand View Research.
But does the evidence actually back up the hype?
The Claim
On TikTok, you'll find content creators praising sea moss for clearing their acne and giving them radiant skin, improving digestion, boosting energy and helping with weight management and better sleep. In the Caribbean, sea moss is sometimes sold in a drink that's said to be a male libido booster, King says.
And in both Ireland and the Caribbean, you can find recipes dating back to the 1800s that treat sea moss as a form of food as medicine.
The evidence
Despite a long tradition of using sea moss for its alleged beauty and wellness boosting properties, "we still don't have much research to support the health claims that our celebrities are endorsing," King says.
Most of the claims are based on cell or animal studies, which don't always translate to humans. "Even the human trials that we have are small and of short duration," says Dr. Melinda Ring, the executive director of the Osher Center for Integrative Health at Northwestern University.
That's not to say sea moss has no health benefits. Ring says sea moss in its whole form is a good source of fiber, antioxidants, vitamins and minerals like zinc, which do support gut health and the immune system. But you can also get these nutrients from lots of other foods, not just sea moss.
"So can it be potentially beneficial? Yes." Ring says. "Can it be more beneficial than other sources? Probably not. It's just one of many things that we can use to support our health."
She says there is emerging evidence that the prebiotic fibers in sea moss can support a healthy gut microbiome.
The risks
But Ring says consuming too much sea moss also poses potential risks. "One is that sea moss can accumulate heavy metals like arsenic, lead and mercury, particularly if it's been sourced from contaminated water. So that's a big concern," Ring says.
A study published in June found that excessive or prolonged consumption of contaminated seaweed can lead to a buildup of heavy metals in the body, posing serious health risks.
Another concern: Sea moss is rich in iodine. We need some iodine for good thyroid health, but too much can potentially trigger thyroid dysfunction.
Ring says people with thyroid disorders or who are pregnant or breastfeeding should avoid sea moss. So should people on blood thinners, because sea moss contains vitamin K, which can interfere with these medications.
If you want to try it
One study found that powdered sea moss — the kind you might find in capsules — contained cadmium and lead at levels that exceeded limits set by California. That's why Ring says, if you do try sea moss, stick to it as a whole food or in gel form instead of supplements. Plus, you'll get more fiber this way, she says.
King notes that the Food and Drug Administration does not regulate supplements with the same rigor as pharmaceuticals. She notes that studies have found that supplements in general can contain way more of an ingredient than they say, so if you do choose to try a supplement, look for one tested by a third party to "make sure you're buying what you think you're buying."
The bottom line
If you want to dip your toes into the sea moss trend, skip the supplements and try cooking with it instead, King suggests.
Or feel free to ignore the whole trend altogether, says Diana Guevara, a culinary registered dietician with the U.T. Health Houston School of Public Health. While sea moss can be healthy, she says it's no magic elixir.
"You know, we want things to be easy and quick," Guevara says.
But when it comes to good health she says, "it really is just that whole lifestyle of including more fruits, more vegetables, more whole grains and really just looking for that balance" in your diet."
It may not be trendiest advice, but it is backed by science.
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