PROBLEM TO BE SOLVED: To provide an agent or a composition for suppressing blood pressure elevation containing, as an active ingredient, a Laminaria japonica fermentation product which is obtained by fermenting Laminaria japonica by Bacillus natto, Laminaria japonica and Bacillus natto being traditionally eaten and safe.SOLUTION: There are provided: functional food, food materials and pet food, for preventing or improving blood pressure elevation, each containing, as an active ingredient, a Laminaria japonica fermentation product obtained by fermenting Laminaria japonica by using Bacillus natto and, as internal agents, compositions for pharmaceuticals (including pharmaceuticals for animals), for drink and food, and for feeding stuff, given to humans or non-human animals.
