Does Irish sea moss have health benefits — and should you try it?

A nutritionist weighs in on what the science says about this so-called superfood.
TODAY Illustration / Shutterstock
By Kristin Kirkpatrick

Irish sea moss is having a moment. Celebrities are talking about it on social media, and consumers are flocking to it as the latest nutritional miracle. The question is: Does all the hype translate to actual benefits to health?

What is sea moss?

Irish sea moss is a type of red algae found on the shores of the North Atlantic surrounding Ireland, Europe and North America. For hundreds of years, it has been used for medicinal purposes. In fact, it got its name because it was often used as a source of nutrients and food during the Irish Potato famine of the 1800s. Like a lot of algae, Irish sea moss contains high amounts of certain nutrients, including folate, vitamin K, iron, iodine, magnesium and calcium.

You’ve probably consumed Irish sea moss in products without even knowing it considering that its extract, carrageenan, is used in hundreds of food products (and cosmetics) as a stabilizing and gelling agent. It’s also often sold raw and it commonly appears as an ingredient in wellness-focused supplements, sea moss gels, Irish sea moss powder and skin care products.

What are the benefits of sea moss? Often touted as a superfood, proponents of the algae claim it can strengthen immunity, improve digestion and make your skin glow. It may even tame a sore throat, they say.

Do the health claims hold up against science?

Because of their high nutrient density, protein content and fiber, sea vegetables have often been considered “functional foods,” meaning that they offer health benefits that go beyond just supplying essential nutrients like vitamins and minerals. A study published in the September 2015 issue of Phycologia, for example, suggested that adding small amounts of seaweed to foods such as hot dogs and frozen pizza may help reduce rates of cardiovascular disease.

Very few studies have looked extensively at Irish sea moss. The ones that have suggest there may be a potential benefit associated with a healthier microbiota. A 2015 animal study published in BMC Complementary Medicine and Therapies found that sea moss may provide prebiotics — a type of fiber that acts as food for probiotics and helps them do their job better — that help boost gut health.

The nutritional components of algae appear to be somewhat dependent on the location where the plant was harvested. Scientists are still learning about how well we digest and metabolize these sea vegetables.

More is not necessarily better

Sea moss, when taken in excess, has the potential to negatively impact health. One of the reasons for this is its high density of iodine. In small amounts, iodine can help with thyroid health, but when consumed in excess, studies show that it may lead to thyroid dysfunction, including hypothyroidism and even thyroid cancer. Excess iodine can also be especially harmful to children. Iodine toxicity may cause nausea and diarrhea.

For anyone considering trying Irish sea moss supplements — rather than raw Irish sea moss — it’s important to remember that the supplement industry is not regulated, which can make it hard for consumers to decipher which Irish sea moss supplements are good quality and which ones may not be. A glut of online videos that claim to “help” consumers identify fake versus real sea moss can make choosing a good quality product even more confusing.

What’s the bottom line?

Irish sea moss has a high nutrient profile and may provide some benefits to your health. However, there is still little evidence to back up the health claims associated with most products. If you’re interested in using Irish sea moss to boost your health, it’s best to consult with your physician or a dietitian first. They can determine if Irish sea moss is right for you. They may also be able to offer guidance on how to use it and how to find high-quality products.