The present disclosure relates to nutritional compositions includinga protein equivalent source including a peptide component comprising selected peptides from Tables 1 and 2 disclosed herein. The protein equivalent source may further include intact protein, hydrolyzed protein, including partially hydrolyzed protein, orcombinations thereof. The disclosure further relates to methods of reducing the incidence of autoimmune disease and/or diabetes mellitus by providing said nutritional compositions to a target subject, which includes a pediatric subject.本發明關於包含蛋白質等效來源之營養組成物,該蛋白質等效來源包括含有選自本文所揭示之表1及2之肽類的肽成分。該蛋白質等效來源可進一步包括完整蛋白質、水解蛋白質(其包括部分水解蛋白質)或彼等之組合。本發明進一步關於經由提供該營養組成物給標的個體(其包括小兒個體)來降低自體免疫性疾病及/或糖尿病之發病率的方法。