To provide an agent for improving diabetes which is easy to take orally and normalizes blood glucose level and HbA1c.SOLUTION: The weight ratio of the mussel meat powder to the mixed powder is 20% to 90%, the weight ratio of the mussel meat extract powder extracted from the mussel meat extracted from lyophilized meat is mixed with another powder, %, Which is a capsule in which the mixed powder is covered with a capsule shell as a content, which is orally administered to a subject having diabetes.(FIG.【課題】経口摂取し易く、血糖値及びHbA1cを正常化する糖尿病の改善予防剤の提供。【解決手段】凍結乾燥後のイガイ肉から抽出されたイガイ肉抽出物の粉末を他の粉末に混合した混合粉末から構成され、前記混合粉末に対する前記イガイ肉の粉末の重量比率が20%~90%であり、前記混合粉末を内容物としてカプセル皮膜で覆ったカプセルである、糖尿病の対象者に経口投与される糖尿病の改善予防剤。【選択図】図4
