Seaweed Benefit: Cancer Prevention

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What are the benefits of seaweeds?

Seaweeds are the general term given to algae that grow in the ocean. Kelps are good examples of marine seaweeds found in the temperate region. Many people around the world use seaweeds for food and medicine. For example, the Japanese people have been using the kelp, Laminaria sp. as a traditional ingredient for their food. They believe in the medicinal properties of the algae which they locally call “konbu.” Other seaweeds that they consume are nori and mozuku. The therapeutic uses of seaweeds are known in Japan for centuries but the scientific investigation of their ability to treat diseases only began in the 1970s. They have already isolated chemical compounds in brown algae that have anti-tumor and anti-cancer properties. Among these are u-fucoidan and laminarin extracted from the central vein of “konbu,” one of Japan’s most popular seaweed.

Various scientists have associated the low incidence of cancer in some parts of Japan to the regular consumption of konbu and other marine seaweeds. For example, Okinawa has the lowest cancer mortality rate in the whole of Japan where people eat konbu raw. Scientists also associated the low breast cancer incidence in Japan to the consumption of edible seaweeds. Due to their anti-cancer properties, konbu and other marine seaweeds are already marketed worldwide as dietary supplements and alternative medicines.

Benefit of Seaweeds: Contain Compounds Against Cancer

One active compound isolated from the brown seaweed Laminaria sp. is u-fucoidan. This complex polysaccharide has been widely studied for its oncological importance. Researches about this compound have been published in reputable journals like the British Journal of Pharmacology, Journal of Molecular Immunology, and Journal of Neuroimmunology. In research performed in Japan, it was demonstrated that cancer cells placed in a laboratory dish were wiped out within 72 hours just by treating them with u-fucoidan. Researchers believe that u-fucoidan induced apoptosis (programmed cell death) to the cancer cells. Apoptosis occur when certain enzymes (produced by the cell itself) digest the DNA into small fragments. U-fucoidan has been administered to stomach, colon, and leukemia cancer cells and apoptosis was observed in all of them. Scientists and pharmaceutical companies are now working very hard to elucidate the biochemical pathways on how u-fucoidan induces apoptosis in cancer cells.

U-fucoidan has also been found to inhibit the physical adhesion of tumor cells to normal tissues. This activity protects tissues from being infected by cancer cells. U-fucoidan therefore has anti-metastatic activity. Scientists hypothesize that u-fucoidan blocks the receptors of normal cells where cancer cells bind.

U-fucoidan also enhances the activity of macrophages in killing tumor cells. Macrophages are responsible in phagocytosing foreign objects like bacteria and tumor cells.

Another compound extracted from Laminaria sp. is laminarin which prevents angiogenesis in tumor cells. Angiogenesis is the vascularization or the formation of blood vessels in tumor cells. It makes tumors grow bigger and more dangerous.


Consumption of products containing u-fucoidan and laminarin is highly advisable because of their ability to kill tumor and cancer cells. Edible kelps would be a good part of our diet because they are rich in u-fucoidan and laminarin. Moreover, these compounds don’t only have anti-cancer properties but also properties that strengthen our cardiovascular system. They are also rich in iodine and other minerals important to our body.


Seaweeds and Cancer.

The Anti-Cancer Properties of Mozuku Seaweed.

Application and Properties of U-fucoidan.