Maternal Intake of Vitamins A, C, D, and E During Pregnancy and Risk of Type 1 Diabetes in the Child: The Norwegian Mother, Father, and Child Cohort Study.

BACKGROUND

Dietary vitamins play a role in antioxidant defense and immunoregulation. However, prospective studies exploring the association between vitamin intakes during pregnancy and the child's risk of type 1 diabetes are limited.

OBJECTIVES

This population-based prospective cohort study aimed to investigate the association between maternal intake of vitamins A, C, D, and E during pregnancy and risk of type 1 diabetes in children.

METHODS

We included 85,244 children born between 2002 and 2009 in the Norwegian Mother and Child Cohort Study, with follow-up until 31 December, 2021. Maternal intake of vitamins from food and dietary supplements from conception to the 22nd week of pregnancy was assessed with a validated food frequency questionnaire. Cox proportional hazards regression was used to estimate hazard ratios (HRs), adjusting for background factors.

RESULTS

During follow-up, 529 (0.6%) children were diagnosed with type 1 diabetes at a mean age of 9.4 y (standard deviation: 4.1 y) No associations were observed between maternal pregnancy intake of vitamin A [HR: 0.993; 95% confidence interval (CI): 0.983, 1.003/100 μg], vitamin C (HR: 1.000; 95% CI: 0.993, 1.007/10 mg), vitamin D (HR: 0.991; 95% CI: 0.978, 1.003/1 μg), or vitamin E (HR: 0.999; 95% CI: 0.996, 1.004/10 mg) and risk of type 1 diabetes in the child when adjusted for potential confounders. The results were similar when intakes were assessed separately from food and dietary supplements and after restriction to children with human leukocyte antigen DQ2 and/or DQ8 risk haplotypes.

CONCLUSIONS

This prospective cohort study does not support the hypothesis that higher maternal intake of vitamins A, C, D, and E during pregnancy would decrease risk of type 1 diabetes in the child. Corroborated with previous evidence, our findings support a general pattern of null associations.