Background: Vitamin deficiencies significantly impact children's growth and development, particularly in high-altitude regions. This study investigated the prevalence and patterns of vitamin A and D deficiencies among children in Tibetan versus non-Tibetan regions of Sichuan Province, China, considering the influences of altitude, gender, and seasonal variations.
Methods: A case-control study was conducted comparing 995 Tibetan children from Garze Prefecture (altitude > 2000 m) with 995 age- and sex-matched non-Tibetan children from Luzhou City during 2017-2019. Vitamin A deficiency was defined as serum retinol < 0.70 µmol/L, and vitamin D deficiency as 25-hydroxyvitamin D < 50 nmol/L.
Results: Tibetan children showed significantly higher rates of vitamin A (47.7% vs. 21.0%) and D (19.8% vs. 10.7%) deficiency compared to non-Tibetan children. Vitamin A and Vitamin D deficiency were more frequent in higher altitudes, with vitamin A (OR 5.2, 95% CI 2.44-11.09) and D deficiency (OR 2.47, 95% CI 1.28-4.77). Female Tibetan children demonstrated higher vitamin D deficiency risk, while summer and autumn were associated with lower vitamin D deficiency risk (OR 0.43, 95% CI 0.29-0.65).
Conclusions: This study reveals substantial disparities in vitamin A and D status between Tibetan and non-Tibetan children, with altitude, gender, and seasonal factors playing crucial roles. These findings emphasize the need for targeted nutritional interventions considering multiple environmental and demographic factors in high-altitude regions.
Keywords: Children; Gender; High-altitude regions; Season; Vitamin A and D deficiencies.
© 2025. The Author(s).