Fucoidan-Rich Seaweed vs. Sea Moss: Health Benefits Compared

Valued for their rich nutrient profile and health-promoting properties, seaweeds are becoming a key ingredient in health and wellness products, from smoothies to skincare. Sea moss (Chondrus crispus) and mekabu (Undaria pinnatifida) are two species of seaweed gaining momentum as superfoods. While both seaweeds have potential health benefits, the strength of scientific research backing these benefits varies.

Sea moss, gaining particular attention, is often celebrated for its rich iodine content, supporting thyroid health, and soothing properties that may support gut health. On the other hand, mekabu, containing the natural compound fucoidan, has been the subject of ongoing research. These studies reveal fucoidan’s promising benefits for human health, including immune support, anti-inflammatory effects and beneficial gut health properties.  

In this article, we’ll delve into the available evidence surrounding these two seaweeds, exploring their health benefits based on their current body of research and determining which marine plant stands out as the more compelling choice as a supplement for human health.

 

Evidence for Sea Moss Health Benefits:

 

Red algae such as Irish moss (sea moss) continues to gain attention in the wellness industry, but what do scientific studies reveal about its potential health benefits?

Research Focus: Most studies on sea moss are animal-based or conducted in labs, with limited direct human clinical trials. Research highlights include its effects on gut health and antioxidant properties. For example, studies show that sea moss acts as a prebiotic[1], feeding beneficial bacteria and improving gut microbiome balance. However, much of this research is preliminary. 

Thyroid and Iodine: Sea moss, like many seaweeds, is a rich natural source of iodine – an essential mineral for thyroid health. Several studies confirm its potential to support healthy thyroid function.[2] However, iodine intake has a ‘sweet spot’ in healthy individuals, as too much iodine intake is not ideal either. In some cases, too much iodine can exacerbate thyroid issues. Read more about seaweed, thyroid health and iodine here. As different seaweeds contain varying levels of iodine, always enquire about the iodine content of a sea moss product and consult a healthcare provider who can help you determine if sea moss is a suitable addition to your routine. Additionally, since seaweeds, including sea moss, can absorb heavy metals from its environment, sourcing and testing matters.

Gut Health: Sea moss is known for its mucilaginous (gel-like) texture which helps soothe the digestive tract and promote regularity.[3] Prebiotic studies conducted in rats also show improvement in gut bacteria populations.[4]

 

 

Evidence for Australian Fucoidan-rich Seaweed Health Benefits:

 

Research Focus: Fucoidan, the bioactive compound found in some species of brown seaweed such as Undaria pinnatifida, has been studied for its wide range of biological activity; some of the actions include immune-boosting[5], anti-inflammatory[6], and anti-viral[7] properties.

Immune Health: Fucoidan has been shown to support the immune system by enhancing the activity of natural killer (NK) cells, which help defend the body against viruses and abnormal cells.[8] Learn more about how fucoidan fortifies the immune system here.

Immune Modulation: Consuming fucoidan extracted from Undaria pinnatifida may have been linked to a decrease in allergic responses.[9]

Gut Health: Fucoidan has also been found to support the microbial environment of the gut[10], contributing to overall gut health. As research evolves, this marine-derived compound presents an exciting avenue for enhancing gut microbiota, supporting probiotic function, and protecting against various gastrointestinal conditions.[11] Deep dive into how fucoidan benefits your gut health and microbiome here.

Clinical Evidence: Numerous clinical trials have tested fucoidan's effects, particularly in the context of immune modulation and reducing inflammation.​ A more substantial body of scientific evidence supports the potential of these benefits compared to sea moss. 

Benefits of Sea Moss vs. Undaria Seaweed	Benefits of Sea Moss	Benefits of Fucoidan/Undaria
Gut health	✓	✓
Prebiotic action	✓	✓
Iodine for thyroid health	✓	✓
Antioxidant	✓	✓
Anti-inflammatory	✓	✓
Carrageenan source	✓
Antimicrobial action	✓	✓
Immune boosting		✓
Immune modulating		✓
Contains fucoidan		✓
Anti-viral properties		✓
Large body of evidence		✓

 

 

Further explanation on the differences between sea moss and Undaria seaweed (including their nutritional profile, origin and culinary uses) can be found here: Sea Moss vs. Seaweed: What’s the Difference?

 

While sea moss presents intriguing potential benefits, particularly for thyroid health and digestive support, much of the existing evidence stems from animal studies and lacks extensive human trials. In contrast, Undaria pinnatifida (mekabu) seaweed is supported by a more robust body of clinical research, particularly regarding fucoidan. Numerous studies demonstrate its positive effects on immune function, inflammation, and gut health. For those seeking a bioactive seaweed supplement backed by more robust research, fucoidan-rich brown seaweeds such as Undaria may be the ideal choice.

 

Curious about how to incorporate seaweed into your routine? Explore our guide on how to select a high-quality natural health supplement.

 

 

 

 

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