Group: Few Reasons to Use Soy Formula

Pediatricians Issue New Review of How Soy Formulas Measure Up to Cow’s Milk

Reviewed by Louise Chang, MD on May 05, 2008
From the WebMD Archives

May 5, 2008 -- What's best to feed baby? According to the American Academy of Pediatrics, mother's breast milk still rules. However, the group finds that when the majority of infants in North America are 2 months old, they are getting at least some formula.

The AAP has released its revised report on using soy protein-based formulas, which may make up almost 25% of the formulas for sale in the U.S.

When to Stay Away From Soy Formula

Soy protein-based formulas are not recommended for babies born prematurely. The AAP says that when it comes to preemies, cow's milk-based formulas designed for preterm babies are "superior."

When babies are allergic to milk, research shows that 10% to 14% of them will also be allergic to soy protein. The AAP says in that case it's best to give hydrolyzed protein formula.

Using Soy Formula

The AAP notes that indications for soy protein-based formulas include:

  • Preference for vegetarian diet
  • Infants with hereditary lactase deficiency (rare) or galactosemia, in which a baby can't metabolize a main sugar in milk (lactose) or a sugar component of it called galactose.

Use of soy formula that is lactose-free may be indicated in babies with lactose intolerance. However, the AAP states that its use should be restricted because very few would need total avoidance of lactose.

What's Bugging Baby?

Many parents turn to soy formulas in their desperation when a little one has colic. The AAP says soy has no proven benefits in managing or preventing colic or the crying and fussiness associated with it.

The AAP says that while the sucrose and fiber in soy formulas may help soothe a colicky baby, studies do not show that soy formulas have the edge over those made from cow's milk.

Colic is still little understood. It often stops on its own when a baby reaches 4 to 6 months of age.

If your infant gets formula as a supplement to breast milk, the AAP states that soy formula has no advantage over cow's milk-based formula unless the baby has one of the indications stated earlier.

There has been some concern that the phytoestrogens in soy formulas may interfere with the immune system, the thyroid, or with how the reproduction system develops.

Soybeans are high in phytoestrogens, which are estrogen-like compounds found in plants or plant products. The AAP says that there is no "conclusive evidence" from any animal, adult, or infant study showing that that eating soy causes problems to "human development, reproduction or endocrine function."

The AAP urges further study on soy-based formulas.

Soy formulas for infants have been on the market for nearly a hundred years. It's believed that between 20% and 25% of the formulas sold in the U.S. are soy-based.

The new AAP report, called "Use of Soy Protein-Based Formulas in Infant Feeding," updates the AAP's 1998 review of soy formulas.