- 2026-04-07
- Nutrients 18(7)
- Yifan Gong
- Xingwen Zhao
- Qi Zhang
- Xinxin Yan
- Bin Sun
- Xinyi Li
- Qixu Han
- Yiran Guan
- Huiyu Chen
- Meina Li
- Jie Guo
- Biao Liu
- Ran Wang
- Baotang Zhao
- Yan Zhang
- Jingjing He
Study Design
- Type
- Randomized Controlled Trial (RCT)
- Population
- 120 healthy children aged 3-6 years from four kindergarten classes
- Methods
- 9-month cluster-randomized, double-blind, controlled trial; children stratified by grade and randomly allocated (1:1) to receive either multi-nutrient fortified formula or standard control milk
- Blinding
- Double-blind
- Duration
- 9 months
- Funding
- Unclear
Background/objectives
The preschool period is critical for neurodevelopment, yet evidence investigating fortified formula's effect and potential microbiota-gut-brain axis mechanisms in this age group is limited. To evaluate fortified formula milk's effect on neurodevelopment and explore potential microbiota-gut-brain axis mechanisms in preschool children.Methods
In this 9-month cluster-randomized, double-blind, controlled trial, 120 healthy children aged 3-6 years from four kindergarten classes were stratified by grade and randomly allocated (1:1) to receive either multi-nutrient fortified formula (intervention, n = 60) or standard control milk (n = 60). Neurocognitive function was assessed using the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV). Safety was evaluated through anthropometry and blood biochemistry. Gut microbiota (16S rRNA sequencing) and fecal metabolomes (untargeted LC-MS) were analyzed at baseline and 9 months.Results
The intention-to-treat (ITT) analysis showed no significant difference in Full Scale Intelligence Quotient (adjusted mean difference: 1.05 points; 95% CI: -1.42, 3.52; p = 0.400). However, the intervention group significantly improved the Processing Speed Index (adjusted mean difference: 5.91 points; 95% CI: 1.88, 9.93; p = 0.004), increased gut microbial alpha diversity (Shannon index) and Bifidobacterium abundance. Metabolomic analysis revealed elevated fecal 2-hydroxybutyric acid (2-HB), a marker of propanoate metabolism. Increases in both Bifidobacterium and 2-HB levels showed a positive association with PSI improvement (both p < 0.05). All children maintained normal growth and safety parameters.Conclusions
Fortified formula milk improved processing speed in preschoolers, a benefit associated with gut ecosystem modulation characterized by Bifidobacterium enrichment and upregulated microbial propanoate metabolism. These results offer preliminary evidence for the role of the microbiota-gut-brain axis in nutritional cognitive programming during early childhood. (Clinical Trial Registry: ChiCTR2400084211).