What is supplemental feeding?
A supplemental feeding is any bottle feeding your baby receives when you are not available to breastfeed. A supplemental feeding might be a refrigerated bottle of breast milk that you expressed (that is, released from the breast into a container) earlier in the day; a bottle of breast milk that you expressed and then froze for future use; or a bottle of infant formula prepared in advance or when needed.

A supplemental feeding is not a bottle that is given after a breastfeeding to "top off" the feeding. You should be aware that feeding your infant in this way can hinder your ability to breastfeed successfully. If your baby is still hungry after a feed, it would be better to switch back to the first breast or to take the infant to the breast more often.

Choosing a supplemental feeding
You may have already discussed with your doctor or other health care professional which type of supplemental feeding would be most appropriate for you and your baby. Of course, breast milk is the best choice. However, the choice between breast milk and formula is a personal one, and should be made with the help and guidance of your health care professional.

If you do choose to supplement with formula, your health care professional can advise you on selecting a formula with the best balance of protein, fat, vitamins, and minerals for your baby. A formula close to breast milk is best for your baby because it can help ensure easy digestion and avoid unnecessary strain on the kidneys.

If you choose to use formula, your health care professional will probably recommend a cow's milk-based infant formula. Standard milk-based formulas are derived from cow's milk, but are modified to improve digestibility. Some of these formulas are patterned after the nutritional profile of breast milk and contain recommended amounts of vitamins and minerals.

Some infants, however, may be allergic to, or have difficulty digesting, cow's milk protein. For these babies, a soy protein-based formula would be the next best alternative. Again, your health care professional is the best source of information.

Weaning foods are not supplemental feedings
You should be aware that other types of feedings—those involving foods such as cereals, for example—are not supplemental feedings. Cereals, fruits, and vegetables are weaning foods and should be introduced to your child sometime between 4 and 6 months of age under the guidance of your health care professional.

Cow's milk is not suitable
Powdered or liquid cow's milk—whole, low fat, or skim—does not make a good supplemental feeding. While it is fine for older children and adults, several researchers have found that for infants younger than 12 months-for whom proper nutrition is crucial-cow's milk is not a suitable food.

Cow's milk does not contain the right balance of nutrients your baby needs. It is deficient in iron, which is important for healthy red blood cells and proper mental development. It also contains too much protein, which can put undue stress on your baby's delicate kidneys. Cow's milk does not contain the proper amounts of other important nutrients, so you should avoid it altogether during the first year.