Medicinal Uses

Important warning: please note that all medicines, including herbal medicines, should be taken only on the advice of a qualified practioner. Many beneficial treatements do not work in particular circumstances and may be antagonistic. For all medicines, a particular dose and course of treatment must be observed; it should be noted that more of a good treatment is not necessarily better. You should not treat yourself on the basis of any information given here.

In Europe and North America, many claims have been made for the effectiveness of seaweeds on human health. It has been suggested, amongst other things, that seaweeds have curative powers for tuberculosis, arthritis, colds and influenza, worm infestations, and may even improve one's attractiveness to the opposite sex. Digenea (Ceramiales; Rhodophya) produces an effective vermifugal agent (kainic acid). Recently, aqueous extracts from two red algae of the family Dumontiaceae have been found to inhibit the herpes simplex virus but no tests have been carried out on humans. Some of the reported medicinal effects of marine algae have not been substantiated. Corallina is being used used in bone-replacement therapy. Stein & Borden (1984) provide an extensive review.

Currently, biologically active natural products are becoming more and more popular among consumers, both in the form of food supplements and cosmetic products, and as medicines. Highly active sulphated polysaccharides isolated from seaweed have numerous important properties: immunomodulatory, antitumor, neuroprotective, antilipidemic, antidiabetic, anti-inflammatory, antioxidant, renoprotective, hepatoprotective, etc. In addition, sulphated polysaccharides are used for controlled drug delivery, wound healing, and regenerative medicine. The therapeutic potential of sulphated polysaccharides allows them to be use for cell therapy and tissue engineering. The use of seaweed sulphated polysaccharides is attractive not only from their unique properties, but also from their low cost, the virtual absence of toxicity and the formation of resistance of pathogens, good solubility, significant reserves of natural sources, and the possibility of seaweed cultivation. All these advantages undoubtedly make these substances promising candidates for the creation of biologically active additives and new generation drugs for the prevention and treatment of diseases of various origins (for further information see here).

"Multiple health benefits have been ascribed to brown seaweeds that are used traditionally as dietary component mostly in Asia. Despite the great diversity of experimental systems in which distinct species and compounds were tested for their effects on inflammation and immunity, a remarkably homogeneous picture is apparent. The predominant effects of consumption of brown seaweeds or compounds can be classified into three categories: (1) inhibition of reactive oxygen species, known to be important drivers of inflammation; (2) regulation, i.e., in most cases inhibition of proinflammatory NF-B signaling; (3) modulation of adaptive immune responses, in particular by interfering with T-helper cell polarization. Over the last few decades, several inflammation-related diseases have increased substantially. These include allergies and autoimmune diseases as well as morbidities associated with lifestyle and aging. Thus, further development of brown seaweeds and seaweed compounds as functional foods and nutriceuticals might contribute to combat these challenges."

Modified from Olsthoorn, S.E.M., Wang, X., Tillema, B., Vanmierlo, T., Kraan, S., Leenen, P.J.M. & Mulder, M.T. (2021). Brown seaweed food supplementation: effects on allergy and inflammation and its consequences. Nutrients 13(2613): 1-59. (Download PDF).

• Some kelps may have polysaccharides that may reduce the incidence of breast cancer.
• Seaweeds in Chinese medicine