The policies regarding the mandatory fortification of food with folic acid (FA) may impact the effectiveness of folate-based B vitamin treatment on cognitive function in older adults. We critically and systematically review the literature to assess whether food fortification policies affect folate-based B vitamin treatment efficacy on cognition function in older adults. Electronic databases, including PubMed, Web of Science, and CNKI, were searched for “Cognitive Function”, “Folate”, and “Older Adults”. The study had specific criteria for inclusion, which were as follows: (1) the studies should initially have randomized controlled trials that were conducted on older adults aged 60 or above; (2) the studies must assess the relationship between folate status and cognitive performance; and (3) the studies should clarify the policies regarding food fortification with FA. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines. Two reviewers independently extracted all the data, and any discrepancies were resolved by consensus. All the data collected were compiled, compared, and analyzed critically. Random effects models were used to assess the effects of interventions. The systematic review included fifty-one articles involving 42,768 participants. Of these, the 23 articles were included in the meta-analysis. The meta-analysis on the effects of folate-based B vitamin supplementation on cognitive function showed a significant overall impact (Z = 3.84; p = 0.0001; SMD, 0.18; 95% CI, 0.09, 0.28). Further analysis revealed that FA food fortification policies were not implemented in countries where folate-based B vitamin supplementation improved cognitive impairment in older adults (Z = 3.75; p = 0.0002; SMD, 0.27; 95% CI, 0.13, 0.40). However, the FA intervention did not have significant outcomes in areas where FA food fortification policies were mandatory (Z = 0.75; p = 0.45; SMD, 0.03; 95% CI, −0.06, 0.13). Supplementing with oral folic acid, alone or in combination, has been linked to improved cognitive performance in older adults. While mandatory FA fortification has the improved folic acid status, additional folate-based B vitamin supplements do not appear to influence cognitive function.

Background: The physical abilities of older adults decline with age, making them more susceptible to micronutrient deficiency, which may affect their sleep quality. Objectives: This study aimed to construct a risk correlative model for sleep disorders in Chinese older adults based on blood micronutrient levels. Methods: In this matched case-control study, we recruited 124 participants with sleep disorders and 124 matched controls from the Tianjin Elderly Nutrition and Cognition cohort in China. Micronutrient levels in whole blood were measured using the dried blood spot technique. We compared the differences in micronutrient levels between the two groups and also constructed a receiver operating characteristic (ROC) model and nomogram for sleep disorders. Results: In comparison to the control group, the sleep disorders group showed lower levels of blood vitamin A, vitamin E (VE), folate, magnesium, copper, iron, and selenium (Se) in the univariate analysis (p < 0.05). The ROC curve analysis indicated that the combination of VE + folate + Se may have an excellent diagnostic effect on sleep disorders, with an area under the curve of 0.964. This VE + folate + Se was integrated into a nomogram model to demonstrate their relationship with sleep disorders. The consistency index of the model was 0.88, suggesting that the model assessed sleep disorders well. Conclusions: The sleep disorders risk correlative model constructed by the levels of VE, folate, and Se in whole blood might show good performance in assessing the risk of sleep disorders in older adults.