The gut–brain axis has received considerable attention in recent years, and the “psychobiotics” concept indicates that probiotics have a potential positive effect on cognitive function. Therefore, the aim of this study was to quantitatively evaluate the influence of probiotics on cognition. We conducted a random-eff ;ects meta-analysis of 7 controlled clinical trials and 11 animals studies to evaluate the eff ;ects of probiotics on cognitive function. Probiotics supplementation enhanced cognitive function in both human (0.24 [0.05–0.42]; I² = 0 %) and animal studies (0.90 [0.47–1.34]; I² = 74 %). Subgroup analyses indicated that the effects of probiotics on cognitively impaired individuals (0.25 [0.05–0.45]; I² = 0 %) were greater than those on healthy ones (0.15 [−0.30 to 0.60]; I² = 0 %). Furthermore, compared with a multiple-probiotic supplement, a single strain of probiotics was more effective in humans. The meta-analysis provided some suggestions for probiotics intervention and tended to support a customized approach for different individuals to ameliorate cognitive disorders. Future additional clinical trials are necessary to evaluate therapeutic effect and influencing factors.

近年来，肠脑轴受到了相当大的关注，“精神药物”的概念表明益生菌对认知功能具有潜在的积极作用。因此，本研究的目的是定量评估益生菌对认知的影响。我们进行了7项对照临床试验和11项动物研究的随机荟萃分析，以评估益生菌对认知功能的影响。补充益生菌可增强人类（0.24 [0.05–0.42]；I ² = 0％）和动物研究（0.90 [0.47–1.34]；I ² = 74％）的认知功能。亚组分析表明，益生菌对认知障碍者的影响（0.25 [0.05–0.45]；I ²= 0％）大于健康者（0.15 [−0.30至0.60]；I ² = 0％）。此外，与多重益生菌补充剂相比，单一益生菌菌株在人类中更有效。荟萃分析为益生菌干预提供了一些建议，并倾向于支持针对不同个体改善认知障碍的定制方法。为了评估治疗效果和影响因素，将来还需要进行其他临床试验。