Infant diet and the child’s health and development – InfaDiet

The project was divided into three work packages. The 1st work package was devoted to the influence of essential nutrients (lipids and proteins) in breast and formula milk on child’s health and development. The 2nd work package was devoted to other components, recently added into formula milk such as pre- and probiotics or only present in breast milk such as complex HMO, immune or inflammatory factors. Breast milk analyses were based on large-scale non-targeted ("omic") methods. In the 3rd work package, we extended our approach to other aspects of infant feeding, such as timing and type of foods used during the complementary feeding period (including organic foods).

The project was based on two French birth cohorts: the regional EDEN cohort (2003–2006, n = 2002) and the nationwide ELFE cohort (2011, n = 18,329). These two cohorts enabled to analyse both short- and long-term health effects, but also to replicate analyses and assess the reproducibility of findings.

We observed a decrease in the protein content of infant formulas between the EDEN study (2003-2006) and the ELFE study (2011). The pooling of data from these cohorts (Camier, 2021) confirmed, in real-world conditions, the results of the 2009 CHOP trial.

Infant formulas based on partially hydrolysed proteins (pHF) are offered with the aim of allergy prevention. Our results (Adjibade, 2024) show, in real-use conditions, that the consumption of pHF infant formulas is associated with a higher likelihood of multimorbid allergic conditions (eczema, food allergies, without asthma).

Before 2020, enrichment of infant formulas with long-chain polyunsaturated fatty acids (LC-PUFA) was not systematic. In the ELFE study, no association was found between this enrichment and cognitive, language, or motor development scores up to 3.5 years (Martinot, 2022). Conversely, an inverse association was observed between this enrichment and the frequency of lower respiratory infections (Adjibade, 2022).

In the EDEN study, approximately 25% of children consumed a formula enriched with pre- or probiotics; this figure was 56% in the ELFE study. In ELFE, the consumption at 2 months of a formula enriched with Bifidobacterium lactis was associated with a lower risk of respiratory illnesses in early childhood (Adjibade et al., 2022). In the EDEN cohort, it was associated with a lower risk of allergy (Adjibade et al., 2024). No clear association was found for formulas enriched solely with prebiotics.

In the ELFE study, among children without allergies at 2 months, late complementary feeding introduction (>6 months) was associated with a higher risk of food allergy. Similarly, delayed introduction of at least two allergens (among egg, fish, wheat, milk) after 10 months was linked to a higher risk of food allergy. Early complementary feeding (<4 months) was associated with a lower BMI in childhood but was not linked to an increased risk of overweight (Camier et al., 2024). Regarding neurodevelopment, we showed that late introduction of food pieces (beyond 10 months) was associated with lower neurocognitive development scores (Somaraki, 2024).

In the national ELFE study, 51% of infants had never consumed foods from organic farming during the complementary feeding period (up to 10 months), 24% sometimes, 15% often, and 9% always or almost always (de Lauzon-Guillain et al., 2021). Organic food consumption is more common among children breastfed for a long time, from more educated families, and often part of feedin practices perceived as “healthier” (home-made foods, lower consumption of sugary drinks), but also among families with a history of allergies (Payet et al., 2021).

These results open significant prospects for research, public health policies, and industrial innovation. In the short term, they reinforce the relevance of recommendations such as introducing major allergens early in the complementary feeding period (between 4 and 6 months old), and early exposure to a variety of textures and foods. In the medium term, they could inform considerations regarding the reformulation of certain infant formulas. From a research perspective, the prospects include integrating omics data, studying the influence of this early diet on the gut microbiota, conducting longer-term follow-ups (pre-adolescence, adolescence), and analysing the mediating or moderating effect of diet during this life stage on the links between prenatal exposures (including maternal diet) and children's health and development.

• Camier A, Chabanet C, Davisse-Paturet C, Ksiazek E, Lioret S, Charles MA, Nicklaus S*, de Lauzon-Guillain B* (2020) Characterization of infant feeding practices during the first year of life and associated familial characteristics in the nationwide ELFE birth cohort. Nutrients. 13:E33. doi: 10.3390/nu13010033.
• de Lauzon-Guillain B, Gaudfernau F, Camier A, Davisse-Paturet C, Lioret S, Nicklaus S, Charles MA, Kesse-Guyot E (2021) Characteristics associated with feeding organic foods during complementary feeding: the nationwide ELFE birth cohort. Br J Nutr. doi: 10.1017/S0007114520005097.
• Camier A, Davisse-Paturet C, Scherdel P, Lioret S, Heude B, Charles MA, de Lauzon-Guillain B. Early growth according to protein content of infant formula: results from the EDEN and ELFE birth cohorts. Ped Obes

InfaDiet is a collaborative project, which aims at studying the influence of infant feeding (milk components & complementary feeding practices) on the child’s health (growth, infections and allergic symptoms) and neurodevelopment. Our main hypothesis is that the beneficial influence of breastfeeding on the child’s health and development is explained by nutritional components of breast milk but also by association of breastfeeding practices with specific complementary feeding practices, such as the more frequent use of fruit and vegetable. The recent evolution of formula milk composition (enrichment with long chain PUFA or with pre/probiotics) offers the opportunity to examine potential nutritional mechanisms, independently of breastfeeding-related practices. Furthermore, we propose to explore breast milk composition, with large-scale non-targeted methods, already developed, to highlight specific components related to the child’s health and neurodevelopment. In this project, child health will be defined by height and weight growth, occurrence of infections and incidence of allergy-related diseases.

Multidisciplinary, InfaDiet associates complementary expertise (4 academic partners from epidemiology, immunology, pediatrics, nutrition and food sciences).

The project is divided into five work packages. The 1st work package will be devoted to the influence of essential nutrients (lipids and proteins) in breast and formula milk. The 2nd work package will be devoted to other components, recently added into formula milk such as pre- and probiotics or only present in breast milk such as complex HMO, immune or inflammatory factors. In the 3rd work package, we will extend our approach to other aspects of infant feeding, such as timing and type of foods used during the complementary feeding period (including organic foods). WP0 will be devoted to the management of the project; and WP4 to the dissemination of its results.

The project is based on two French birth cohorts. These two cohorts are complementary, as the EDEN cohort (recruitment in 2003-2006, n=2002) is a bicentric regional study that benefits from a long follow-up (up to age 12 years) and a large biological biobank, whereas the ELFE cohort is nationwide, more recent (recruitment in 2011, data already available up to age 3.5 yrs), larger (n=18,329), benefits from biobanking on specific aspects. These two cohorts will enable to analyse both short- and long-term health effects, but also to replicate analyses and assess the reproducibility of findings. Similar findings in both cohorts will reinforce the level of evidence.

The impact of this project will be major for research and public health in the field of infant diet for which the scientific knowledge is largely insufficient in comparison with the important societal expectations. The project is innovative and transdisciplinary as it plans to unravel for the first time all the dimensions of infant diet, from infant feeding practices to nutritional content of breast and formula milk, as well as their interrelationships in connection to complementary feeding. These dimensions of infant diet will be examined in real conditions of use and related to several aspects of infant health and development. Our approach will provide original data to improve the current nutritional recommendations concerning this key period of life, as well as on the links between the use of organic foods at a very sensitive period of development and the child’s health. Finally, as the prevalence of allergic diseases increases, understanding how to prevent allergy is an urgent priority and this project could lead to early nutrition recommendations for primary prevention of allergic diseases.