ABSTRACT
Background
Potential positive link between cognitive function and dietary restriction has been widely concerned. The present study describes a systematic review and preliminary meta-analysis to assess the efficacy of dietary restriction on cognitive function. We classified dietary restrictions as Calories Restriction (CR) and Intermittent Fasting (IF).
Method
This systematic review and meta-analysis conducted following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Statement (PRISMA) Checklist, Databases including PubMed, Embase, Web of Science, and the Cochrane Library were searched for randomized controlled trials (RCTs) assessing the cognition effectiveness of dietary restriction from database inception to Sep 2021.
Result
Eleven RCTs met the inclusion criteria in the systematic review and meta-analysis. The overall effect of dietary restriction on cognitive function is SMD = 0.22 (95% CI: 0.09–0.34, p < 0.01). The effect on global function SMD = 0.35 (95% CI: 0.04–0.65, p < 0.05) and memory SMD = 0.18 (95% CI: 0.00–0.35, p = 0.05) is significant. MCI showed the best effectiveness SMD = 0.36 (95% CI: 0.05–0.68, p < 0.05), followed by the normal weight population SMD = 0.28 (95% CI: 0.03–0.52, p < 0.05) and overweight population SMD = 0.20 (95% CI: 0.06–0.34, p < 0.01). No statistically significant difference showed between IF and CR (p > 0.05).
Conclusion
Our study demonstrated that dietary restriction has varying degrees of positive effect on cognitive function in overweight/normal-weight people and MCI. However, it should be cautious when generalizing to other populations. Additional high-quality, large-scale, cohort and intervention studies are needed to further assess the effectiveness of dietary restriction on cognition.
Data availability statement
All data included in this study are available upon request by contact with the corresponding author.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Additional information
Funding
Notes on contributors
Wenqi Lü
Wenqi Lü, MS Resident in the Department of Psychiatry, West China Hospital SCU. has research interests in nutrition and neuropsychiatric diseases. Committed to advancing the research of mental health.
Tingting Yu
Tingting Yu, MS, has clinical experience in the field of psychogeriatrics at West China Hospital SCU and Chongqing Mental Health Center.
Weihong Kuang
Weihong Kuang, MD, Professor, Chief Physician, Department of Psychiatry, West China Hospital SCU, has been engaged in clinical service of mental health and medical management of the Psychiatry for more than 20 years. Specializes in sleep disorders, anxiety and depression disorders, memory and cognitive disorders, and neuropsychiatric disorders clinical diagnosis and treatment; Focuses on clinical and basic research in psychopharmacology and neuropsychiatric disorders. More than twenty National Natural Science Foundation of China, Provincial and Ministerial research Funds, and GCP research projects have presided over and participated. More than 90 articles have been published in related journals.