How can seaweed boost our immunity?

Seaweed against immunity

Immunity, the key to our health

We are constantly exposed to aggressors such as viruses and bacteria that try to pass through the barriers of our body to proliferate. Although these intrusions are common, recent food contamination events or even the COVID19 epidemic have shown that these aggressions pose serious dangers to our health. Solutions must be found to avoid the recurrence of such crises.

To defend against these attacks, our body possess a powerful tool called the immune system. The immune system involves many organs, cells and proteins that act together to first recognize an invader, and then to fight it until it is destroyed. However, although our immune system has a powerful arsenal to defend us, there are times when it is overwhelmed by the aggressor or fails to act in time to eliminate the threat and expose us to the contamination.

In this concern to help the immune system to identify and eliminate threats, a lot of research has been conducted to find molecules that can stimulate our immunity and help our body to defend itself.


Seaweed to the rescue of our immunity

Recently, there has been a particular interest in seaweeds and their abilities to stimulate our immune system.

Seaweeds, in addition to their interesting content of vitamins and minerals that help our immunity, are particularly rich in fibers. Some seaweed have sulfates on their surface that make them very effective in fighting viruses and pathogenic bacteria1. For example:

  • red seaweeds have carrageenans;
  • brown seaweeds have fucoidans;
  • green seaweeds have ulvans.

Among the latter, carrageenans, present in red algae such as Chondrus crispus, have shown a potential to stimulate immunity and limit the proliferation of viruses and bacteria.

Numerous clinical trials have highlighted the anti-viral effect of carrageenan intake, whether in gel form against sexually transmitted viruses such as papillomavirus2, or in nasal sprays was very effective in preventing contamination by respiratory viruses such as the common cold3. More recently, results have even shown that the use of carrageenan in nasal sprays showing a positive effect on the reduction of COVID19 contamination by significantly limiting the positivity of the PCR tests of the treated persons compared to those who received a placebo treatment4.


Seaweeds integrated in the future treatments?

Poorly exploited for current time, but arousing a strong therapeutic interest, seaweeds will perhaps provide tomorrow the active ingredients that will help our body to defend itself and prevent the future epidemic events.

To learn more about the many health benefits of seaweed, you can read our previous expert files:


1)Wei, Q., Fu, G., Wang, K., Yang, Q., Zhao, J., Wang, Y., … & Song, S. (2022). Advances in research on antiviral activities of sulfated polysaccharides from seaweeds. Pharmaceuticals, 15(5), 581.
2) Novetsky, A. P., Keller, M. J., Gradissimo, A., Chen, Z., Morgan, S. L., Xue, X., … & Einstein, M. H. (2016). In vitro inhibition of human papillomavirus following use of a carrageenan-containing vaginal gel. Gynecologic oncology, 143(2), 313-318. DOI: 10.1016/j.ygyno.2016.09.003
3) Fazekas, T., Eickhoff, P., Pruckner, N., Vollnhofer, G., Fischmeister, G., Diakos, C., … & Lion, T. (2012). Lessons learned from a double-blind randomised placebo-controlled study with a iota-carrageenan nasal spray as medical device in children with acute symptoms of common cold. BMC complementary and alternative medicine, 12(1), 1-8. DOI: 10.1186/1472-6882-12-147
4) Figueroa, J. M., Lombardo, M., Dogliotti, A., Flynn, L. P., Giugliano, R. P., Simonelli, G., … & Uchitel, O. (2021). Efficacy of a nasal spray containing Iota-Carrageenan in the prophylaxis of COVID-19 in hospital personnel dedicated to patients care with. COVID-19 disease. A pragmatic multicenter, randomized, double-blind, placebo-controlled trial (CARR-COV-02). medRxiv. DOI: 10.1101/2021.04.13.21255409