The effect of consuming processed Akamoku (Sargassum horneri) products with rice on blood glucose dynamics

Akamoku (Sargassum horneri) is brown algae widely distributed along the coast of Japan except in eastern Hokkaido. Although it is traditionally considered inedible in many regions, it has gained popularity nationwide as a food source. When boiled, this species turns vibrant green and develops a distinctive sticky texture. We aimed to explore the effect of incorporating commercially available boiled Akamoku or microwave-boiled Akamoku into breakfast or lunch meals along with rice on postprandial blood glucose dynamics. The experiment included three distinct test meals: a standard meal comprising rice, soup, and seasoning; an Akamoku-enriched meal incorporating commercially available processed Akamoku with standard components; and a microwave-boiled Akamoku meal with standard meal components. The blood glucose dynamics in these three dietary conditions were compared among healthy adult male and female participants using the FreeStyle LibreR flash glucose monitoring system. The results suggested that both boiled Akamoku and microwave-boiled Akamoku exhibited a notable effect in suppressing the rate of blood glucose increase. However, no significant influence on the reduction or delay in the maximum postprandial blood glucose level, rise value, rise and fall times, or incremental area under the curve was observed. These findings indicate that while the ingestion of boiled or microwave-boiled Akamoku effectively attenuates the rapid postprandial rise in blood glucose levels, it does not impede bodily absorption of sugars or nutrients.