Most estimates value the global sea moss market at around $2.5 billion, and Grand View Research projects it will reach $3 billion by 2030.
The United States is one of the fastest growing markets. According to data from market research firm SPINS, sales more than doubled in 2025 compared to the previous year, rising from $19.5 million in 2024 to $53.3 million in 2025.
This growth can largely be attributed to increased public discourse on social media, with the hashtag #seamoss garnering over 1.5 billion views on TikTok. This follows increased attention after celebrities like Kim Kardashian, Hailey Bieber and Dua Lipa reportedly added the algae to their wellness routines.
Often marketed as containing 92 minerals, sea moss comes in a range of formats including gels, powders, drinks and gummies. It is touted as having a range of potential benefits, from thyroid and immunity support to digestion and skin health.
“While sea moss primarily lives in the superfoods category within SPINS, which is up 128.8% in dollar growth, its perceived benefits extend into several adjacent, growing subcategories that reinforce how shoppers are thinking about it, including hydration and electrolytes, minerals, antioxidant supplements, beauty supplements, prebiotics and probiotics, and immune supplements,” said Rahul Roy, senior insights manager at SPINS.
“Importantly, while sea moss supports a range of wellness needs, it is not positioned as a complete nutritional solution,” he added. “Instead, its appeal lies in how easily it complements existing supplement stacks, helping shoppers enhance hydration, mineral intake and beauty or digestive routines without replacing established core products.”
However, skeptics warn that there is little scientific evidence to support sea moss supplementation, as most published studies use animal or cell models. There are also concerns surrounding heavy metal and iodine content, raising important questions surrounding sourcing and safety.
History of sea moss consumption
Archaeologists estimate that humans have been harvesting seaweed, like Irish sea moss (scientifically known as Chondrus crispus) for nearly 14,000 years.
Irish sea moss, which grows in cooler waters along the rocky shores of the British Isles, North America and Europe, is the most nutrient-dense and sought-after form of sea moss. Other types of sea moss grown in the Caribbean, such as Gracilaria and Eucheuma, are also commonly found in supplements.
A recent study published in Nature Communications found that seaweeds like Chondrus crispus and other local freshwater plants were consumed in Europe during the Mesolithic period (8000 BC)—the final period of hunter-gatherer cultures—through to the Neolithic transition and into the Early Middle Ages.
By the 18th century, seaweed was considered a famine food, consumed widely in Ireland during the Great Famine (1845-1852). In fact, the term Irish moss is thought to reflect the the long history of sea moss consumption in the country.
The Irish believed that carrageenan, a natural polysaccharide found in red seaweed, could cure sick calves and human colds and flus. It was added to foods like Irish pudding and Blancmange, with the compound still used today as a thickener, gelling agent, stabilizer and emulsifier in various foods and personal care products.
Some sources state that the influx of Irish immigrants popularized sea moss in the Caribbean after many settled in the islands during the 19th century. Others track Caribbean sea moss consumption back to the Late Middle Ages, when indigenous populations used it as a natural remedy for immune and digestive health. Today, sea moss punch—a mix typically made with milk, sweeteners and spices—is a popular drink throughout the islands.
Sea moss, as a dietary supplement, was only popularized in the last decade, receiving a surge in attention following the death of Alfredo Darrington Bowman, better known as Dr. Sebi, a Honduran herbalist and self-proclaimed holistic healer.
Dr. Sebi was a controversial figure who, despite his self-issued title, had undergone no medical training and falsely claimed that mucus was the root cause of all disease. He maintained that eating an ‘alkaline diet’, high in fruits, vegetables, nuts, seeds and legumes, and avoiding meat, dairy and processed items could stave off diseases, including cancer and AIDS.
Sea moss was highly recommended in Bowman’s alkaline diet, as he believed it helped the body to maintain an alkaline state and eliminate mucus. After his death in 2016, public discourse surrounding sea moss grew louder.
Bowman died from pneumonia contracted in police custody in Honduras after being arrested for money laundering. Conspiracy theories started to circulate, with many of Dr Sebi’s fans claiming he was silenced because his alkaline diet threatened major pharmaceutical companies. The theories only intensified after rapper Nipsey Hussle, who was making a documentary about Dr. Sebi, was shot in 2019.
While there is no firm evidence to substantiate these claims, this sequence of events propelled sea moss into the mainstream, with an array of celebrities jumping on the trend.
Now, sea moss supplements are sold in more than 65 countries, with over 14,000 brands offering formulations, according to Market Reports World. Large U.S. retailers like Sprouts sell sea moss supplements from a range of brands, including Mary Ruth’s, Cymbiotika and Lemme.
Surging interest also fueled the growth of a host of African American-owned start-ups, including The Transformation Factory, Plant-Based Jeff and Bey Moss, with many sourcing sea moss from local harvesting and farming businesses in the Caribbean. In fact, the surge in demand generated new income streams for many coastal communities, particularly for women supported by Food and Agriculture Organization training and equipment in Dominica, Grenada and St. Lucia.
“A big part of the momentum is cultural and social,” Roy said. “Sea moss gained early traction through Caribbean and holistic wellness communities, then scaled quickly through social platforms where preparations, gels and smoothies made it feel authentic and accessible. That exposure is pulling in younger shoppers who are already comfortable experimenting with food-first and plant-based wellness.”
Evolution of sea moss supplement formats
Today, the sea moss found in supplements is predominantly wildcrafted Irish moss (gathered from rocks and ocean surfaces) or Caribbean sea moss grown on ropes. The latter method uses species like Gracilaria and Eucheuma which are farmed and ‘bleached’—a natural process that happens when sea moss is dried in the sun.
Dried sea moss can be formulated into a variety of supplement formats, including gels, capsules, gummies and drinks. Gummies and RTDs are newer formats, with Wixar Naturals launching the first commercially available sea moss gummy in 2020, and actor Michael B. Jordan launching the first shelf-stable sea moss drink, MOSS, in 2024.
Gels, however, are arguably the most popular way to consume sea moss. Made simply by blending sea moss with water—sometimes with the addition of flavorings—the gel is typically stored in the fridge to prevent spoilage and bacterial growth. This factor has made it challenging for some sea moss brands to enter retail, according to Noel Lattie, founder of UK-based brand Lattie’s Sea Moss.
“Gel is the preferred method of consumption, but until now, it has only been available as a chilled product with a short shelf-life,” he said. “This makes it tricky to list from a retailer’s perspective as the risk of wastage and consequently lost margin is higher. The chilled nature makes it almost impossible to sell online, too, given the requirement for chilled fulfilment.
“We have always been aware of this problem, and we created the most retail-friendly sea moss gel in the market,” Lattie added. “By making it easier for retailers to list, we hope to get this amazing superfood in front of more people across the country.”
While consumer awareness of sea moss is still fairly low compared to other dietary supplement ingredients, Lattie said launching in large retailers such as Holland & Barrett has increased sales. The brand’s consumers are primarily younger people looking for immunity, skin health and athletic performance benefits, tying in with the ingredient’s significant online presence.
“When talking with consumers, we know that sea moss’s high mineral content is the reason why people take the product as it is often hard to consume these important micronutrients in a normal diet,” Lattie said. “Being minerals, the integrity of these is not affected by processing, so customers can be sure these nutrients are present in the product. However, we are in the process of getting our product tested, so we know exactly what minerals are in the product.”
Health benefits and risks of sea moss: What the science says
Scientific research confirms that sea moss is a nutrient-dense substance which contains high levels of minerals such as iodine, calcium, potassium and iron, along with smaller levels of magnesium, manganese and copper. It also has all nine amino acids and is a good source of fiber and polyunsaturated fatty acids.
“According to our research, sea moss is an important source of certain micronutrients that are often lacking in Western diets, such as zinc,” said José Manuel Miranda Lopez, a professor in nutrition and bromatology at the University of Santiago de Compostela, Spain.
However, whether sea moss contains the purported 92 minerals is up for debate, according to Claire Edgemon, senior registered dietitian at Baylor College of Medicine, Texas. Edgemon pointed out that sea moss absorbs minerals from the water it is grown in, so its mineral content largely depends on growing conditions. In addition, the human body only needs 13 essential minerals to perform vital functions, with others only needed in trace amounts.
“A serving of sea moss can provide about 12 of the essential minerals in appropriate amounts,” she said. “Sea moss can absorb minerals from the water, so there is the potential for the sea moss to contain other minerals. However, not all of those minerals are essential for the body—some could be toxic when consumed in high levels.”
Despite uncertainty surrounding its exact mineral content, sea moss’s nutrient profile suggests that it may offer a number of health benefits. For example, iron boosts immunity, calcium contributes to bone density, and zinc supports hormone synthesis. However, clinical trials are lacking.
Animal studies suggest that sea moss may have immunomodulatory and digestive health properties. For example, one study in rats found that Chondrus crispus may influence the composition of gut microbial communities, improving gut health and immune modulation. Miranda Lopez said this is largely due to the seaweed’s prebiotic properties.
“Once it reaches the colon, it promotes the growth of beneficial bacteria such as Bifidobacterium adolescentis and Lactobacillus ruminis,” he said. “It also increases the production of short-chain fatty acids, which are important for the proper maintenance of the digestive epithelium.”
Because of its high iodine content, sea moss is often marketed to support thyroid hormone regulation. However, this type of seaweed sometimes contains such high levels that it can pose a risk, Edgemon said.
“The biggest concern is a high intake of iodine which could cause thyroid issues or cancer,” she said. “Also, sea moss could interfere with blood thinners as it contains vitamin K.”
While iodine is known for its critical role in thyroid function and hormone production, too much of this mineral can overstimulate or suppress thyroid function. Again, iodine content varies greatly depending on where sea moss is grown, making this an important consideration for consumers, particularly those with pre-existing thyroid issues.
Another concern is heavy metal content. As sea moss naturally absorbs minerals from the surrounding water, industrial pollution and runoff can therefore increase heavy metal levels, making sourcing location another critical consideration.
“It’s hard to know exactly what you are getting since sea moss will pick up whatever is in the water where it grows,” Edgemon said. “So, if it grows in water near industrial pollution, it will have higher amounts of toxic metals, such as arsenic, mercury and lead.”
Many sea moss brands use seaweed sourced from the Caribbean, with St. Lucia and Jamaica both major exporters. While some brands refer to this water as ‘pristine’, the United Nations Environment Programme states that pollution from maritime transportation, untreated domestic wastewater and poor agricultural practices continue to impact the Caribbean Sea.
This is not to say that all sea moss sourced from the Caribbean contains heavy metals. For example, London-based brand Sea Moss Boss uses hand-harvested sea moss from Canouan Island in St. Vincent and the Grenadines. The company provides publicly available third-party heavy metal testing, showing that its sea moss contains negligible levels of lead and mercury.
Other companies use sea moss grown off the coast of Ireland or other European coasts, where marine water quality can vary. Miranda Lopez et al. tested sea moss grown on the Spanish Atlantic coast for both heavy metal and iodine content and found it to be safe.
“In our case, heavy metals such as copper, mercury, arsenic and lead were not found to pose any risk to human health,” he said. “The iodine content, which is a frequent problem due to possible excess related to seaweed consumption, was also low. However, these results refer only to sea moss collected on the Spanish Atlantic coast. Other studies have found higher iodine content, which may pose a risk to people with thyroid-related conditions.”
As consumer awareness of these risks grows, many sea moss brands are now beginning to provide third-party testing results to reassure consumers, with some also including warning labels for individuals with thyroid issues.
Dietitians such as Edgemon tend to err on the side of caution, recommending that consumers seek out brands which offer third-party testing and keep to a maximum dose of 4 to 8 grams per day.
“[Sea moss] is generally safe as it is considered similar to other seaweeds,” she said. “In general, it is better to eat the whole food or take it as a gel. A supplement might be too concentrated in iodine or toxic metals. Groups that shouldn’t take sea moss include those with thyroid issues, those taking blood thinners, or women who are pregnant or breastfeeding.”