Vitamin D plays a crucial role in calcium and phosphate metabolism, which are essential for the mineralization of bones and teeth. Primary tooth enamel and dentin begin forming during fetal development, primarily from the second to third trimesters, when adequate mineral availability is critical. Low maternal vitamin D levels during pregnancy have been hypothesized to affect offspring tooth development, potentially increasing susceptibility to early childhood caries (ECC), a highly prevalent chronic disease in young children.
A large prospective cohort study published in JAMA Network Open 1in December 2025 evaluated the association between maternal vitamin D and childhood dental caries among 4,109 mother–offspring pairs enrolled at Zhoushan Maternal and Child Health Hospital in Zhejiang Province, China. Pregnant women were enrolled between August 2011 and May 2021, and their children’s oral health was followed until November 2022.
Maternal plasma 25-hydroxyvitamin D (25[OH]D) levels were measured in the first, second, and third trimesters. Vitamin D deficiency (VDD) was defined as total maternal 25(OH)D concentration <20 ng/mL, in accordance with clinical guidelines. Children underwent standardized dental examinations between ages 1 and 6, with early childhood caries (ECC) defined as one or more decayed, missing, or filled primary teeth.
Of the 4,109 children studied, 960 (23.4%) were diagnosed with ECC by their latest dental visit. Approximately 76.6% of children did not have caries.
The researchers observed that higher maternal 25(OH)D levels across all trimesters were consistently associated with lower odds of ECC in offspring.
In statistical models adjusted for maternal age, education, body mass index, gestational age, feeding patterns, and child characteristics such as age at dental exam, the following trends were noted:
First trimester: Higher 25(OH)D levels were associated with slightly reduced ECC risk.
Second trimester: Increased maternal vitamin D remained inversely associated with ECC odds.
Third trimester: The association persisted, with maternal levels linked to lower ECC risk.
Additionally, higher maternal vitamin D was associated with lower dmft scores (a measure of decayed, missing, and filled primary teeth) and reduced caries rate in children, particularly in the second and third trimesters.
Vitamin D influences fetal calcium and phosphate homeostasis, both essential for enamel and dentin formation. Functional vitamin D receptors are found in cells involved in tooth development, such as ameloblasts (enamel-forming cells) and odontoblasts (dentin-forming cells). Inadequate maternal vitamin D may disrupt mineralization, potentially increasing vulnerability to tooth decay in early childhood.
Although earlier randomized clinical trials of vitamin D supplementation reported mixed results on dental outcomes, this large observational cohort provides robust evidence that supports the biological theory of prenatal vitamin D influencing dental health in offspring.
The findings suggest that maintaining sufficient vitamin D status throughout pregnancy, including before conception and into the later trimesters may help reduce the risk and severity of early childhood dental caries. These results support consideration of maternal vitamin D screening and supplementation in prenatal care, especially in populations at high risk for deficiency.
1. Xu, Nuo, Zexin Chen, Boya Wang, Yiwen Qiu, Xialidan Alifu, Haibo Zhou, Haoyue Cheng, Ye Huang, Libi Zhang, Hui Liu, Lina Yu, Danqing Chen, and Yunxian Yu. “Vitamin D Levels During Pregnancy and Dental Caries in Offspring.” JAMA Network Open 8, no. 12 (2025): e2546166. https://doi.org/10.1001/jamanetworkopen.2025.46166