Seaweed: An Uncommon Solution to the Common Cold

When someone says the word “seaweed,” what comes to mind? If you spend any time at the beach, you probably think of scraggly looking green or brown strands washed up on the sand, or wispy tendrils that brush against your legs while you crash in the waves. Or maybe, if food is your thing, you picture certain traditional eastern treats, such as sushi rolls, soups, and seaweed-based noodles. But did you know that there’s a lot more to seaweed than meets the eye? New research is taking seaweed well beyond the coast and the kitchen, and is exploring applications that few would have thought possible.

In fact, seaweed might actually be a cure for the common cold.

Carrageenan: the seaweed extract of a thousand uses

Before we get into exactly how seaweed is being used to fight colds, let’s take a moment to talk about carrageenan.

Carrageenan is a highly viscous, gel-like substance that comes from a kind of seaweed known as “Irish moss” (scientific name Chondrus crispus). Archaeological evidence shows that seaweed was first used as food around 400 BCE (Before Common Era) by people living on the coast of Ireland (hence the name “Irish moss”), but there are also indications that it was being used medicinally in China as much as two hundred years before that. Whatever the case, these early groups in Ireland discovered that seaweed made a nutritious addition to their standard diet, thanks to its high vitamin and mineral content.

And along with the nutritional benefits, they discovered other uses for Irish moss. By washing and boiling the seaweed, they found that they could extract the natural carrageenan, which could then be added to soups, gellies, puddings, and other foods, making them thicker and creamier.

Today, carrageenan is produced in much the same way, and is still used as a thickener and a stabilizer in a variety of foods. But now, rather than being used exclusively by groups on the coast of Ireland, it’s incorporated as a proven ingredient into thousands of different products all around the world. Carrageenan can be found in yogurts, beverages, syrups, lunch meats, and even baby formula. At the same time, carrageenan is also useful in cosmetics and toothpaste (to name only a few).  

But curing the common cold? Well, it all comes back to carrageenan’s unique physical properties, and the way that the cold virus infects the human body.

Going viral

Despite its name, the common cold isn’t actually a single virus; it’s an entire class of viruses that operate in a similar way and produce similar symptoms. This is, in part, why the common cold is so difficult to treat. Every one of the more than 200 viruses that fall under the umbrella term of “common cold” has its own unique chemical/genetic makeup, and its own built-in strategy for avoiding the body’s natural defenses. This creates big problems for us. The immunities we develop to combat any single one of the viruses may be (and usually are) completely ineffective against the next one to come along, which also makes vaccinating against the common cold all but impossible.

But despite the range of viruses associated with the common cold, they all affect the body in roughly the same way - by lodging themselves in the lining of our throats and nasal passages.

Viruses, carried on our hands or via tiny droplets of infected saliva in the air, can end up making their way into our nose, mouth, or eyes (which drain down into the nasal cavity). From there it’s just a matter of the virus doing what it does best, and once we’re infected we can expect about coughing, sneezing, maybe a fever, etc.

But our bodies don’t just give up. As soon as the virus takes root, the body responds by secreting mucus in the affected area — usually the nose. The mucus traps the virus so that it can then be expelled from the body (and hopefully into a soft and lotioned tissue). This is effective, because mucus is a highly viscous, gel-like substance.

Hmm. “Highly viscous” and “gel-like..." now where have we heard those descriptors used before?

Carrageenan knows nose

That’s right, carrageenan’s special properties make it an effective answer to viral infection. When administered directly to the nasal passage in the form of a nasal spray, it latches onto viruses, rendering them incapable of infecting or multiplying. Think of it as something like fly paper for colds. And because it fights viral infection by trapping the virus rather than by creating antibodies, it’s similarly effective across the entire range of common cold viruses.   

Cold sufferers just take a few sprays a few times a day, and the duration and severity of their colds are cut down significantly.

And, because medical science likes to be sure of this sort of thing, carrageenan’s antiviral properties have been tested again and again and again, and the results are always the same. Carrageenan, as an ingredient in nasal spray, does what few other treatments have been able to do — it holds the common cold virus at bay and even puts it out of commision, quickly and effectively.

The seaweed solution to common colds

So, the next time you see seaweed, remember that there’s more to it than just what keeps your sushi roll from falling apart. Carrageenan, extracted from Irish moss, is used in a number of applications, and based on a lot of research, it may actually hold the key to finally beating the sore throats, runny noses, and coughing fits that we all fall prey to.

The truth is that there’s a lot more to seaweed than meets the eye or nose. With carrageenan-based antiviral nasal sprays, we’re discovering an uncommon solution to the common cold.

8/25/2022 4:00:00 AM
Indy Summers
Written by Indy Summers
Indy Summers is a freelance writer interested in healthy living and fitness. She has been working as a master esthetician, as a personal trainer, and as a model for several years, before becoming a freelance writer. Indy's writing interests include: healthy living, fitness, beauty hacks, cooking and fashion tips. She has...
View Full Profile

I have read elsewhere that it is a cancer causing agent.
Posted by Belinda Lonergan
Carrageenan is a stomach irritant. I avoid it at all costs.
Posted by Judith Haines does not provide medical advice, diagnosis or treatment nor do we verify or endorse any specific business or professional listed on the site. does not verify the accuracy or efficacy of user generated content, reviews, ratings or any published content on the site. Use of this website constitutes acceptance of the Terms of Use.
©2022 Wellness®.com is a registered trademark of, Inc. Powered by Earnware