The Right Formula?
Soy Milk vs. Cow's Milk
Nov. 20, 2000 -- When Lori Oliwenstein-Kluger gave birth to
daughter Emily, she breastfed her for the first 10 months, supplementing with
soy formula when necessary. Then Lori and her husband decided it was time to
switch to a bottle full-time. But they faced a big choice: Which kind of
formula would be best?
They gave cow's milk formula a try, even though they'd both had
trouble with it themselves as children. As it turned out, their suspicions were
right: Emily promptly came down with diarrhea. So they switched to a soy
formula, and Emily did fine.
For these parents and some others, choosing between formula
types is a "no-brainer" since it's based on the comfort and symptoms of
their child. But for parents whose babies can tolerate either type, the
decision isn't so simple.
The American Academy of Pediatrics (AAP) recommends that
parents give soy formula only to infants who cannot digest cow's milk or
to those whose parents wish them to follow a vegan diet. For the majority of
infants, the AAP says cow's milk formula is still the next best thing to breast
milk. Yet the popularity of soy formulas among U.S. parents has increased, with
1 in 4 now opting for soy, according to the academy's estimates.
With growing attention to the possible health benefits of soy
products, parents may be choosing this type of formula thinking it's healthier
for their babies. But the AAP says it may not be so. And while the academy
doesn't claim that soy formula will lead to the development of health problems,
some experts aren't so sure.
The estrogen connection
The main concern about soy formula is that it contains high
levels of phytoestrogens -- estrogen-like substances found in some plants.
People who are worried about soy formula fear that these substances could
interfere with a child's development and even cause early puberty, thyroid
problems, breast development in male children, or other difficulties. Because
of these concerns, a consumer group in New Zealand tried to have soy formula
removed from the market in the mid-1990s. That didn't happen, but the New
Zealand Ministry of Health did issue an advisory opinion to parents in 1998
recommending cow's milk formula over soy.
The next year, the concern crossed the globe when the Canadian
Health Coalition, a group of consumers and health care professionals, called on
the Canadian government to restrict the use of soy formulas there. So far the
restriction hasn't come to pass, but the debate continues. Today, about one in
five Canadian infants uses soy formula, according to estimates from the Infant
Feeding Action Coalition in Canada.
Going too far?
Some experts contend that the anti-soy campaigns have gone too
far. Kenneth D.R. Setchell, PhD, a researcher and professor of pediatrics at
Children's Hospital Medical Center in Cincinnati, believes the fears about soy
milk causing developmental problems are unfounded. He points out that the
studies that sparked the New Zealand outcry were done in animals, not people.
And while soy can cause some endocrine disruptions in animals, humans
metabolize soy very differently, he says.