Creatine supplementation has been put forward as a possible aid to cognition, particularly for vegans, vegetarians, the elderly, sleep deprived and hypoxic individuals. However, previous narrative reviews have only provided limited support for these claims. This is despite the fact that research has shown that creatine supplementation can induce increased brain concentrations of creatine, albeit to a limited extent. We carried out a systematic review to examine the current state of affairs. The review supported claims that creatine supplementation can increases brain creatine content but also demonstrated somewhat equivocal results for effects on cognition. It does, however, provide evidence to suggest that more research is required with stressed populations, as supplementation does appear to significantly affect brain content. Issues with research design, especially supplementation regimens, need to be addressed. Future research must include measurements of creatine brain content.

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肌酸补充剂研究未能支持影响认知的理论基础：来自系统评价的证据

肌酸补充剂已被提出作为一种可能的认知辅助手段，特别是对于纯素食者、素食者、老年人、睡眠不足和缺氧的个体。然而，之前的叙述性评论只为这些说法提供了有限的支持。尽管研究表明补充肌酸可以导致大脑中肌酸浓度增加，但程度有限。我们进行了系统审查以检查当前状况。该评论支持了补充肌酸可以增加大脑肌酸含量的说法，但也证明了对认知影响的结果有些模棱两可。然而，它确实提供了证据表明需要对压力人群进行更多研究，因为补充剂似乎确实会显着影响大脑内容。研究设计的问题，特别是补充方案，需要解决。未来的研究必须包括测量大脑肌酸含量。