The first model of keeping energy balance and optimal psycho affective development: Breastfed infants

Background: Breastfed infants follow a peculiar growth fashion characterized by a rapid weight gain in the first weeks of life, then followed by a fast decrease in growth rates, a capacity to self-regulate the sense of hungry and satiety, and a minor propensity towards overweight and obesity later on, in parallel with a better neurodevelopmental performance.

Methods: We searched studies investigating the relationship between the feeding mode in infancy and the energy balance, so the possible associations with total energy expenditure and intake regulation. We focused the research on the interaction with the neuropsychological development and the possible role of microbiome in determinating the normal generation and regular functioning of the brain through the so named "gut-brain axis".

Results: Total energy expenditure (TEE) is different for breast-fed and formula-fed infants, in particular the feeding mode seems to affect the sleep organisation. Long-term breastfeeding, is one of the most studied factors of neurodevelopment, several studies reporting beneficial effects on child neuropsychological development. Probably this effect is modulated by genetic variations in fatty acid metabolism. Increasing data also showed that the intestinal microbiome exerts several functions which are able to influence neurodevelopment.

Limitations: There is considerable controversy over whether nutrition in early life has a long-term influence on neurodevelopment. Other studies are needed to confirm the association between breastfeeding and brain development.

Conclusions: The key points of energy disposal, the role and effects of the instestinal flora represent promising fields of investigation possibly leading to indications for the wide area of preventive medicine.