A recent large scale evidence review has demonstrated the importance of exclusive breastfeeding to 6 months with partial breastfeeding continued though the first year of life, but few studies have considered whether starting solids earlier than 5-6 months, but with continued breastfeeding, increases the risk to health or causes earlier cessation of breastfeeding.
The review also found new evidence from the developing world that giving extra iron in children who are not short of iron may cause increased infections and slower growth. Formula milks which have higher iron content than either breast milk or doorstep milk are currently recommended from 6 months to 12 months where an infant is not breastfeeding to prevent iron deficiency anaemia and iron fortified follow on formulas are widely advertised. However the potential risks of iron supplemented formula milks have never been examined.