Impact of maternal dietary carbohydrate intake and vitamin D-related genetic risk score on birth length: the Vitamin D Pregnant Mother (VDPM) cohort study

Abstract

Background Our objectives were to investigate the relationship between maternal vitamin D status and IGF-1 levels in healthy Minangkabau pregnant mothers and their impact on newborn anthropometry outcomes and to examine whether this relationship was modified by dietary intake using a nutrigenetic approach. Methods Healthy singleton pregnant mother and infant pairs (n = 183) were recruited. We created three genetic risk scores (GRSs): a six-SNP GRS based on six vitamin D-related single nucleotide polymorphisms (SNPs) involved in the synthesis of vitamin D (vitamin D-GRS), a two-SNP GRS using SNPs in VDR genes (VDR-GRS) and a four-SNP GRS using SNPs from DHCR7, GC, CYP24A1 and CYP2R1 genes (non-VDR GRS). The effect of the GRSs on IGF-1, vitamin D and newborn anthropometry and the interaction between the GRSs and dietary factors were tested using linear regression analysis. Results The vitamin D- and non-VDR GRSs were significantly associated with lower 25(OH)D concentration (p = 0.005 and p = 0.001, respectively); however, there was no significant association with IGF-1, and newborn anthropometry outcomes. However, there was a significant interaction of VDR-GRS with carbohydrate intake on birth length outcome (Pinteraction = 0.032). Pregnant mothers who had higher carbohydrate intake (405.88 ± 57.16 g/day) and who carried ≥ 2 risk alleles of VDR-GRS gave birth to babies with significantly lower birth lengths compared to babies born to mothers with < 2 risk alleles (p = 0.008). Conclusion This study identified a novel interaction between VDR-GRS and carbohydrate intake on birth length outcome. These findings suggest that reducing the intake of carbohydrates during pregnancy, particularly for those who have a higher genetic susceptibility, might be an effective approach for preventing foetal growth abnormalities.

Associations between Vitamin D Deficiency and Carbohydrate Intake and Dietary Factors in Taiwanese Pregnant Women

“…In our study, carbohydrate intake was significantly negatively correlated with 25(OH)D levels in the group with high carbohydrate intake, i.e., ≥300 g/day carbohydrate intake which was based on two-fold between EAR and RDA from IOM (U.S.) and Taiwan’s Dietary Reference. Only a few studies have addressed the relationship between VD and high carbohydrate intake [ 17 , 18 ]. Bolesławska et al reported that the 25(OH)D concentration was significantly higher in the low-carbohydrate-high-fat diet group than in the Eastern European diet group [ 41 ].…”

“…However, few studies have addressed the relationship between Vitamin D and carbohydrate intake. Nutrigenetic studies in Indonesia demonstrated that the relationships between vitamin D, body fat percentage and newborn anthropometry was modified by high carbohydrate intake (mean 405 g/day and 319 g/day carbohydrate intake) [ 17 , 18 ]. But there was no exact cut-off value of high carbohydrate intake in these studies.…”