Objective: Gagome kombu (Kjellmaniella crassifolia), an edible brown seaweed grown around the southern area of Hokkaido, is known to abundantly contain fucoidan. Previous studies show that on animals, fucoidan from Gagome kombu (GKF) exhibits immune-enhancing, anti-cancer and anti-influenza virus capabilities. In this study, we focused on the elderly and evaluated the safety and immune-efficacy of GKF.
Methods: Eighteen (18) Japanese elderly subjects were chosen to ingest the test samples (3 tablets/day containing 50 mg GKF and lactic acid bacteria) for 8 weeks. Before ingestion and every 4 weeks thereafter (4^th and 8^th week), blood chemistry analysis, hematological analysis, urinalysis and immune analysis were conducted.
Result: Test results showed no adverse clinical changes in blood and urinary analysis. In addition, no serious symptoms were observed. Moreover, GKF markedly decreased serum IgE levels.
Conclusion: These results indicate that in the case of elderly, GKF is a safe functional food ingredient.

Objective: Fucoidan, a sulfated polysaccharide in Gagome kombu (GKF) is known to exhibit immune-enhancing and anti-cancer activities. Recently, cancer patients use various dietary supplements containing fucoidan and mushroom extracts. However, there have been few reports on the safety and efficacy of fucoidan-containing supplements. In this study, we examined the safety of long-term ingestion of GKF in cancer patients.
Methods: Twenty six (26) Japanese cancer patients—16 of whom (male 6, female 10, age 62.8 ± 10.7) have completed cancer treatment and 10 (male 4, female 6, 67.0 ± 10.6) still under treatment and regularly taking anti-cancer drugs and hormone pills—were chosen to ingest GKF-containing supplements (200–300 mg/day) for 8 weeks. Before ingestion and every 4 weeks thereafter (4^th and 8^th week), blood chemistry analysis, hematological analysis, urinalysis and immune analysis were conducted.
Result: There were no adverse clinical changes in blood and urinary analysis. In addition, no serious adverse effects were observed.
Conclusion: These results indicate long-term ingestion of GKF is indeed, safe for cancer patients.