[PROBLEMS] To provide an agent and a food which have no adverse side-effects, can be ingested continuously and has an activity of lowering the serum triglyceride level. [MEANS FOR SOLVING PROBLEMS] An agent for ameliorating the lipid metabolism and an agent for lowering the serum triglyceride level, each comprising a culture of a bacterium belonging to the genus Bacillus as an active ingredient. The bacterium is preferably Bacillus subtilis, more preferably Bacillus subtilis C-3102 (FERM BP-1096). The agent for ameliorating the lipid metabolism and the agent for lowering the serum triglyceride level are useful for the treatment and prevention of a disease such as arterial sclerosis.
