I would like to know whether exclusive breastfeeding is shown to be better than a combination of breast milk and formula, in developed countries.
The current advice of the World Health Organization (WHO) is that six months of exclusive breastfeeding leads to best health outcomes for the child. This means that the child is fed on demand, only with breast milk, for a full six months. Solid foods and liquids other than milk are not recommended.
I have seen this same recommendation on all the baby websites I've looked at (here is one example), and it has been repeated to me by a pediatrician, different nurses, and a lactation specialist, all in The Netherlands.
Formula-feeding (with no breast milk alongside it) leads to more hospitalizations for gastric and breathing problems.
However, there are two ways to non-exclusively breastfeed:
1) Introduce solid food before an infant is a full six months old. Evidence from the UK suggests that introducing solids earlier than six months has no adverse health outcomes. In fact, children who are exclusively breastfed are at a higher risk for iron deficiency.
2) Introduce formula alongside breast milk. This is the topic I am interested in.
I am looking for evidence that compares exclusive breastfeeding to half-breast milk, half-formula, in developed countries.
The WHO has to give recommendations that are not only simple and clear, but that pertain to the whole world. I am skeptical about how well this recommendation for exclusive breastfeeding translates into the wellbeing of children in developed countries. Is there evidence to support the WHO's recommendations?