Recent studies show that early introduction of solids replaces breast milk. When this happens, there are no advantages in terms of increased energy intake. Exactly the opposite can happen, in that the baby and mother can face problems. Food often can be contaminated and can cause diarrhea. Poorly digested solids can interfere with the absorption of the essential nutrients from breast milk. Replacing breast milk with poorly digested solids can lead to a decrease in energy intake and can cause malnutrition. Early introduction of solids has been associated with an increase in respiratory infection, wheezing, asthma and eczema. Early exposure to cow’s milk can increase the risk of early onset of diabetes. In addition, supplemental water is often contaminated by nitrates and can have a high content of minerals, which increases the load to the infant’s kidneys. In relation to the mother, early introduction of solids can lead to the early return of menstruation and, as a consequence, the mother loses additional iron stores (for lactation and for menstruation). The return of menstruation can also result in a pregnancy before the mother’s body is ready and while the infant is still too young.
Many mothers are tempted to introduce solids earlier than recommended. For example, a mother can think that the increased demand of her baby to nurse, caused by a growth spurt, is a time for introduction of solids because the baby starts crying much more and seems hungry. She may be getting pressure from her family that it is time for solids, or there may be pressure from her doctor if the baby’s weight gain is less than expected. Studies have revealed that the weight gain of an infant on formula and one on breast milk are not the same. Breastfed babies are lighter than their formula fed counterparts, but this does not mean that they are underweight. Since the length and head circumference of the formula fed and breastfed baby are similar, it means that formula fed infants are simply fatter.
It also needs to be remembered that recommendations on the feeding of formula fed infants, unfortunately, are very often applied to breastfed infants. For example, water and early introduction of iron fortified cereals are important for infants who are formula fed. For the formula fed infant, water is necessary due to the high mineral content of formula or cows milk. Iron is poorly absorbed from cow’s milk or formula, even if this is iron fortified formula, so early supplementation for formula fed infants might be a factor of prevention of anemia or dehydration.
But the same approach for a breastfed child is not appropriate, as breast milk contains enough water and the mineral content of breast milk does not require additional fluid to be given to the infant. In addition, the iron status of an exclusively breastfed full term healthy infant is efficient for the first 6 months and even longer in some cases, especially if the umbilical cord is not clamped immediately after birth.