Provided is a composition and a method for improving brain function via oral administration at low dose. According to the present invention, a composition for improving brain function containing X-Pro-Pro-Leu-Thr-Gln-Thr-Pro-Val-Val-Val-Pro-Pro-Phe-Leu-Gln-Pro-Glu-Y (wherein, X is absent or represents one of Ile or Asn-Ile,wherein,Y is absent or represents Val-Met) or X-Val-Val-Val-Pro-Pro-Phe-Leu-Gln-Pro-Glu-Y (wherein,X is absent or represents one of Thr-Gln-Thr-Pro, Pro-Leu-Thr-Gln-Thr-Pro, Leu-Thr-Gln-Thr-Pro or Pro, wherein,Y is absent or represents Val-Met) or salt thereof as an active ingredients,is provided. Also a method for improving brain function by admistrating these peptides or their salt, is provided.本發明提供用於改善腦機能,可以低用量經口攝取之組成物及方法。根據本發明係提供以X-Pro-Pro-Leu-Thr-Gln-Thr-Pro-Val-Val-Val-Pro-Pro-Phe-Leu-Gln-Pro-Glu-Y(式中,X不存在或表示Ile或Asn-Ile中之任一者,式中,Y不存在或表示Val-Met)或X-Val-Val-Val-Pro-Pro-Phe-Leu-Gln-Pro-Glu-Y(式中,X不存在或表示Thr-Gln-Thr-Pro、Pro-Leu-Thr-Gln-Thr-Pro、Leu-Thr-Gln-Thr-Pro或Pro中之任一者,式中,Y不存在或表示Val-Met)或該等之鹽作為有效成分之腦機能改善用組成物,及經由投予該等肽或其鹽而改善腦機能之方法。由於本案的圖為試驗數據,並非本案的代表圖。故本案無指定代表圖。
