The American Academy of Pediatrics Committee on Nutrition states that when a baby's breast milk intake is adequate, the order in which other foods are added to the infant diet is not critical. A study published in Pediatrics (Dewey 1996) shows that the low protein in breast milk does not limit the growth of exclusively breastfed infants. It is important to remember, however, that when solid foods are introduced, the amount of breast milk a baby consumes decreases. If protein, zinc, or other nutrients are not provided in solid foods, the amount a baby receives from breast milk could be insufficient for optimal growth during the weaning period. Therefore, adding meat to the diet early in the weaning period may be beneficial.
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In short, the amount of breast milk a baby consumes decreases after solid foods are introduced. Important nutrients most likely to be in short supply during the weaning period include protein, zinc, iron, and B-vitamins. Meat is a very good source of all these nutrients and, therefore, is an important part of the infant's diet during weaning. The incidence of allergic reactions to meat is minimal, and lower still when pureed varieties are used.
It is also important to remember that when solids are first given to baby, it is as an introduction and small supplement. Breast milk will still be the baby's primary nutrition for quite some time. Solids are introduced individually about a week apart and only in very small amounts. With this slow introduction, it will be quite a while before baby is relying on solids for his/her basic nutrition. Therefore, it is important that the foods which are given provide the nutrients which are needed most for growth and health.