Doctor: Manik Kadawathagedara
Title: Maternal Diet During Pregnancy and Early Growth : Focus on Diet Duality and Food Chemicals Exposure
Supervisor: Blandine de Lauzon-Guillain
Doctoral school: ED 420. Doctoral school of Public health, University Paris Saclay
Date of thesis defense: 16/01/2018
Jury: Blandine de Lauzon-Guillain, Marie-Christine Boutron-Ruault, Martine Vrijheid, Isabelle Momas, Katia Castetbon, Jean-François Huneau, Claire Philippat
Thesis summary:
Maternal diet is the only prenatal source of nutrients and the major source for non-nutrients and can influence foetal growth and offspring’s long-term health. Chemicals known as “obesogens” might also play a role in increasing obesity risk and one of the main route of exposure to these chemicals is through foods. After a description of diet quality during pregnancy, the aim of this thesis was to study the association between prenatal exposure to food chemicals and prenatal and postnatal growth among children.MethodsWe used the data of three birth cohort studies: two French studies (EDEN and ELFE), and a Norwegian study (MoBa). We first described the compliance to dietary guidelines of French pregnant women and the impact of a better diet quality on birth outcomes using the data of the ELFE study. Secondly, we studied the relationship of a specific food contaminant, acrylamide, on birth size in the EDEN and postnatal growth in MoBa. Finally, we extended analyses to all available food chemicals in the second French Total Diet Study (TDS).ResultsThe nutritional guidelines for pregnant women were rather well followed in ELFE. The diet quality score was associated with higher birth weight and lower risk of having a small for gestational (SGA) baby. We showed that prenatal dietary exposure to acrylamide was associated with reduced birth size in EDEN, and to increased postnatal growth in MoBA. In EDEN, on the 99 selected food chemicals, birth weight was associated with eight chemicals (four negatively and four positively). BMI at 5 years was associated with one food chemical. These results were not significant after correction for multiple testing. When using the mixture approach, one mixture of chemical was positively associated with postnatal growth.ConclusionsThe diet quality score was associated with higher birth size. Whereas dietary exposure to acrylamide was associated with impaired foetal growth, when looking at a larger number of food chemicals, we did not find concerning association on child prenatal or postnatal growth. Exposure to food chemical assessed by TDS did not appear to be of major concern for growth but other windows of susceptibility, such as early childhood, and other outcomes, such as cognitive development, should be considered in future studies.