A recent analysis of The Environmental Determinants of Diabetes in the Young study found maternal diet has no impact on type 1 diabetes and islet autoimmunity (IA) risk.
“Our results do not support the avoidance of gluten-containing or other foods during late pregnancy to modify the risk of T1D disease in offspring,” the researchers wrote.
Although dietary factors may contribute to the development of IA—the asymptomatic prediabetic period—or T1D, previous research has shown conflicting results regarding the relationship between maternal gluten intake and offspring risk of T1D.
Furthermore, “relatively fewer studies have explored the relationship between maternal diet during pregnancy and the development of IA or T1D in offspring, despite the well-documented impact of maternal nutrition on fetal development and childhood health outcomes,” the authors said.
To better understand this relationship, they assessed data from The Environmental Determinants of Diabetes in the Young (TEDDY) multicenter observational study. TEDDY follows children from birth until age 15 living in the United States, Finland, Germany, and Sweden.
As part of the study, “environmental triggers during late pregnancy and infancy, including duration of breast feeding and timing of complementary food introduction, are closely monitored.”
Study visits are completed every third month until the age of 4 and every sixth month afterwards. A total of 21,589 infants, screened between September 2004 and February 2010, met inclusion criteria based on human leukocyte antigen (HLA) genotyping; 8556 were included in the current analysis.
Basic demographic and maternal characteristics were also assessed, including any family history of diabetes. Food frequency questionnaires (FFQs), consisting of 36 food items or groups, were used to collect information on maternal dietary intake in the eighth or ninth month of pregnancy.
At the end of February 2019, 791 cases of IA and 328 cases of T1D had developed. Approximately 11% (n = 951) of those included had a first-degree relative with T1D while 39% (n = 3339) had the highest risk HLA-DR3/4 genotype, the researchers wrote.
Findings were robust to sensitivity analyses that examined differences by HLA genotype and country of origin, while additional adjustments for characteristics previously associated with IA or T1D did not alter findings.
However, “we cannot exclude the possibility that maternal gluten consumption may act in concert with offspring gluten exposures, such as the timing of gluten introduction during infancy or childhood gluten intake, that have been previously associated with risk of IA or T1D,” the authors wrote.
Findings also may have differed had researchers assessed second-trimester eating habits instead of third-trimester gluten consumption.
Because maternal FFQs were collected before development of offspring outcomes, reporting of food consumption is not subject to recall bias.
“Study participants represent the population most likely to develop T1D—children of European ancestry carrying higher-risk HLA genotypes. Our results are therefore generalizable to similarly high-risk populations,” the researchers concluded.
Johnson RK, Tamura R, Frank N, et al. Maternal food consumption during late pregnancy and offspring risk of islet autoimmunity and type 1 diabetes. Diabetologia. Published online March 30, 2021. doi:10.1007/s00125-021-05446-y