The Importance of Milk Composition in Early life to meet infants changing needs

How do infants’ growth and development change over time?

Infant growth changes a lot during the first year.  It is very rapid in the beginning and it decreases with time. Therefore the composition of the milk has most likely developed to fit those needs.

How does breast milk composition evolve to meet infant’s changing needs?

The breast milk’s concentrations of particular protein change a lot early on and that may have several reasons. Several of these proteins are protective and of course the infant is most vulnerable when he is new-born and very young. Immunoglobulins for example, are high in breast milk and several others protective proteins are also very high but they decrease in concentration relatively soon during the first month of lactation. On the other hand breast milk volumes taken in by the infants increase. Therefore the intake numbers of these components don't change as dramatically as the concentrations in the milk, since the mother is capable to produce more and more milk particularly during the first month of lactation.

 What are the short and long term health outcome differences between breast and formula fed infants?

If we talk about infections the breast-fed infants have benefits when it comes to prevention of infections during the first year of life. So the short term benefits when it comes to preventing upper respiratory disease, otitis media in particular, and those things. If we are talking about development in general, we also talking about brain development, cognitive development and there you also see a difference just after one year. So it is relatively short term.

Long-term we see a difference in many of the chronic diseases that we don’t want to see. We see certainly obesity increasing, on those formula-fed, we see more type 1 diabetes, type 2 diabetes, cardiovascular disease. Such diseases that are long term we see the difference.

Even if there are socioeconomic factors that differ between breastfed and formula-fed infants if you tried to you control for those co-founders there are still differences in long-term outcomes which we would like to try to minimize as much as we can.

What is the main nutritional contribution in infant’s long term health?

#I am fairly convinced even, if I don't have evidence that is the protein concentration of the formula. In principle virtually all formula-fed infants or hipper insulinemic that means that higher serum insulin than breastfed infants and that could be a predisposing factor for obesity and obesity is a predisposition factor for type 1 and type 2 diabetes, so anything we can do to reduce the protein content without having any adverse effects would be beneficial in the long term perspective.

On the other hand it is difficult to do those studies because we can get infants during the first year of life but then to follow them up to 6, 7 years, when they start school, when they are teenagers, those studies are very costly and very difficult to do. However those are the types of studies that we need to do to confirm the hypothesis that high protein intake would have long-term adverse effects.

What would be the ideal staging schedule for infant formula during the first year of life?

Ideally, as narrow as possible early on as it is the most vulnerable period of development.

Today infant formulas are a compromise because they need to mix the requirements of an infant that is six months with the one that is new-born and that it is in Europe. In the US you have to mix the requirement of the twelve month old infant to that of a new-born infant, so there are compromises in there. If you introduce the concept of staging it is possible for each time interval get much closer to the goal. Therefore staging, I think, it's a very practical and biological approach to matching what the breastfed infant has seen that is the development of a nutrient intake with age. That is the idea  behind staging approach.

Can proper staging based on infant needs help close the health outcome gap between breast and formula fed infants?

I certainly believe so but we don't have the evidence for that.

When it comes to health outcomes, when it comes for illnesses for example, I don’t think yet you will see much, because you are changing the composition to target the metabolic needs. You are not really changing any of the factors that would be preventing acute illness during the first year of life.

So therefore what you would have to look at are long-term outcomes like: childhood obesity, childhood diabetes, these need to be large size studies to show benefits. I'm optimistic at such benefits will be found.