Introduction Myopia is a common refractive disorder in adolescents, and its association with the gut microbiota remains incompletely defined. Methods We performed 16S rRNA sequencing on fecal samples from 102 adolescents (49 myopic, 53 non-myopic; aged 6–18 years) and analyzed microbial diversity, taxonomy, function, and random forest-based classification, stratified by sex Results Myopic adolescents showed lower gut microbial richness (observed and Chao1, both P 0.05) than non-myopic controls, but overall community structure did not differ. Sex-stratified analyses revealed that these diversity reductions occurred only in myopic males (all α-diversity indices, P 0.01), not in females. Several genera differed between myopic and non-myopic males (e.g., lower Akkermansia, Alistipes, Oscillibacter; higher Veillonella, Sutterella), whereas fewer differences were found in females. Functional predictions indicated altered metabolism and immune pathways. A random forest model achieved moderate overall accuracy (AUC = 76.84%), with higher performance in males (89.13%) than females (69.21%). Discussion Adolescent myopia is associated with reduced gut microbial richness and sex-specific compositional changes, particularly in males, underscoring the importance of sex in gut–eye axis research.
Luan et al. (2026) studied this question.