PROBLEM TO BE SOLVED: To provide a muscle atrophy inhibitor and/or a muscle synthesis promoter which have a function of suppressing atrophy of muscle and/or promoting synthesis of muscle in an organism by preventing reduction of a muscle mass or increasing a muscle mass, and are useful in prevention or treatment of various types of myopathy such as sarcopenia and disuse muscle atrophy, and food and drink for preventing muscle atrophy and/or promoting muscle synthesis in which the muscle atrophy inhibitor and/or the muscle synthesis promoter are blended, a nutritive composition for preventing muscle atrophy and/or promoting muscle synthesis, and feed for preventing muscle atrophy and/or promoting muscle synthesis.SOLUTION: A muscle atrophy inhibitor and/or a muscle synthesis promoter contain milk-derived basic protein fraction and/or a degraded product of milk-derived basic protein fraction, and whey protein hydrolysate as an active ingredient. Since the muscle atrophy inhibitor and/or the muscle synthesis promoter of the present invention have a significant effect of preventing reduction in muscle mass or increasing muscle mass, they are useful in preventing or treating various types of myopathy such as sarcopenia and disuse muscle atrophy.COPYRIGHT: (C)2015,JPO&INPIT【課題】筋肉量の低下を防止する、あるいは、筋肉量を増加させることにより、生体内で筋肉の萎縮を抑制する、及び/又は筋肉の合成促進する作用を有し、サルコペニアや廃用性筋萎縮等の種々の筋疾患の予防や治療に有用である筋萎縮防止及び/又は筋合成促進剤及び、該筋萎縮防止及び/又は筋合成促進剤を配合した筋萎縮防止及び/又は筋合成促進用飲食品、筋萎縮防止及び/又は筋合成促進用栄養組成物、筋萎縮防止及び/又は筋合成促進用飼料を提供することを課題とする。【解決手段】乳由来塩基性タンパク質画分及び/又は乳由来塩基性タンパク質画分分解物とホエイタンパク質加水分解物を有効成分として含有することを特徴とする筋萎縮防止及び/又は筋合成促進剤。本発明の筋萎縮防止及び/又は筋合成促進剤は、筋肉量の低下を防止する効果や筋肉量を増加させる効果が顕著であるため、サルコペニアや廃用性筋萎縮等の種々の筋疾患の予防や治療に有用である。【選択図】なし
