PROBLEM TO BE SOLVED: To provide an inhibitor against increase in a blood GIP level and/or a blood insulin level (preventive and ameliorating agent for diabetes) that does not deteriorate the blood sugar level.SOLUTION: There are provided an oral administration preparation, a blood GIP level increase inhibitor, a blood insulin level increase inhibitor, a preventive and ameliorating agent for diabetes, each comprising a &beta-chitin nanofiber. The &beta-chitin nanofiber has preferably an average fiber width of at most 100 nm.COPYRIGHT: (C)2011,JPO&INPIT【課題】血糖を悪化させることのない血中GIP及び/又は血中インスリン上昇抑制剤(糖尿病予防・改善剤)の提供。【解決手段】β-キチンナノファイバーを含む、経口投与剤、血中GIP上昇抑制剤、血中インスリン上昇抑制剤、糖尿病予防・改善剤。β-キチンナノファイバーは、平均繊維幅が100mn以下のものが好ましい。【選択図】なし
