Background: Short status of children has captured extensive attention since it reflects the health status of children and affects physical and psychological health throughout children's life. Compelling evidences have revealed that gut microbiota participates in the skeletal development directly or indirectly. Currently, the calcium agent and growth hormone-like drugs have provided potential opportunities to promote growth and development among children, yet limited trials existed with probiotic intake as a primary strategy. Objectives: Present cohort study was designed to evaluate the height-promoting effect of gut probiotic Bifidobacterium animalis subsp. lactis BL-11 among 3-7 years old children. Registered under ClinicalTrials.gov Identifier no. ChiCTR2400089723. Methods: This study was conducted with Chinese children aged 3 to 7 years (n = 124) who fall between the 3rd and 25th percentiles (P3-P25) for height, and whose annual growth rate in height is less than 5 cm. The Bifidobacterium animalis subsp. lactis BL-11 oiling agent were taken every day with total live bacteria ≥ 30 billion. The height of each participant was measured and recorded before and after three-months Bifidobacterium animalis subsp. lactis BL-11 intervention. Results: Bifidobacterium animalis subsp. lactis BL-11 could strikingly promote the height growth of children, and shift the height percentile rage from P3-P10 to P10-P25. Importantly, this promoting effect has no specificity between age and sex. Comparatively, children with shorter height (P3-P10) were more sensitive to Bifidobacterium animalis subsp. lactis BL-11. Conclusions: Administration of Bifidobacterium animalis subsp. lactis BL-11 as early as possible is in favor of the child's growth and development, which provided a strategy for pediatricians to address some plights that how to promote children's growth effectively and safely.

The authors have declared no competing interest.

ChiCTR2400089723

This study did not receive any funding

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Ethics committee of the second affiliated hospital of anhui medical university gave ethical approval for this work (ethics number: SL-YX2023-172) Ethics committee of the Chinese Clinical Trial Registration Center gave ethical approval for this work (registration number: ChiCTR2400089723)

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All data produced in the present study are available upon reasonable request to the authors