The Right Formula?
Soy Milk vs. Cow's Milk
Going too far? continued...
If soy formulas caused problems, Setchell says, physicians
would have noticed it by now. Soy milk has been given to infants for centuries
in Asian countries, according to the AAP, and in this country since 1909.
Setchell's views are supported by British pediatrician Charles
Essex, MD, who wrote in the Aug. 31, 1996, British Medical Journal that
there is virtually no data on the effects of phytoestrogens on children. He
also noted that pediatricians have not reported large numbers of male infants
developing breasts or other female traits because of soy formula. Still, he
acknowledged that the long-term effects of soy are not known.
Nutritionally speaking, soy and cow's milk formulas are
similar. Both include vitamins A, D, E, and K. The main difference is in their
protein and sugar make-up.
Cow's milk is processed into formula by heating and other
methods that make the animal proteins in the milk more digestible. Supplemental
milk sugar (lactose) is added to mimic the higher sugar content of breast milk.
Finally, the fat (butterfat) is removed and replaced with vegetable oils or
animal fats, which are also easier to digest.
Soy formulas, which contain plant proteins and glucose or
sucrose (rather than lactose), have changed greatly since they were first
introduced. In the past, they included soy flour, which led to diarrhea, excess
gas, and fussiness. Today, the formulas contain a soy protein isolate, which
reduces the frequency of gastrointestinal problems.
The quality of protein in cow's milk formulas is a bit better
than that in soy, but neither type is as good as that in breast milk, says the
AAP. And lactose-free cow's milk formulations are now available for infants
that are lactose intolerant.
The bottom line
There's clear consensus among most pediatricians that breast is
best. The AAP recommends breast milk for the first 12 months if possible. Short
of that, it recommends cow's milk formula as a first choice and soy as an
alternative for vegans. But Essex also notes that if an infant is thriving on
soy formula, parents should probably leave well enough alone.
Lori Oliwenstein-Kluger says she is comfortable with her
choice. Today, 3-year-old Emily is doing well, but Lori will soon revisit the
formula decision -- her son is due in January. Will she give him soy milk as
well? She admits to some moments of doubt, wondering if the phytoestrogens
might cause some hormonal problems. But her pediatrician has helped quell those
concerns, and she now plans to breastfeed as long as possible, then switch him
to a soy-based formula.
And her pediatrician thinks that's a fine plan.
Kathleen Doheny is a Los Angeles journalist and a contributing
editor for WebMD. She also writes for Shape, Working Woman, and Fit
Pregnancy magazines and The Los Angeles Times.