August 2, 2010, Updated September 13, 2012

The sooner a baby is exposed to cow’s milk, the lower its chances of developing dangerous allergies later on, say Israeli researchers.


After decades of being told breast is best, now researchers have discovered that early exposure to cow’s milk can protect a child from milk allergies.

Early exposure to protein from cow’s milk within the first 15 days of life may increase resistance to dangerous allergies later on, according to extensive new research.

The research, by Israeli scientists, overturns decades of medical advice from doctors and lactation experts suggesting that babies shouldn’t receive milk protein until they are several months old.

Led by pediatrician Prof. Yitzhak Katz, of Tel Aviv University, the study was the longest and most extensive of its kind. His team examined more than 13,000 infants and found that babies who are fed cow’s milk in the form of infant formula during their first 15 days of life seem to be protected from developing cow’s milk allergy later on.

“Women who introduced their babies to cow’s milk protein early almost completely eliminated the incidence of allergy to cow milk protein in their babies,” says Katz.

Protection from dangerous allergies

In the study, the researchers looked at the feeding history of 13,019 infants. Children who were started on infant formula containing cow’s milk protein in the first 15 days of life were almost completely protected from developing Cow’s Milk Protein Allergy (CMA) -19 times more protected than babies fed cow’s milk protein after 15 days.

CMA can be dangerous to babies, leading to rashes, respiratory problems, shock and even death. The boost to the immune system early in life acts as a ‘vaccination,’ said the researchers.

At this point, Katz can’t say how much formula is needed to produce the protective effect, but the pediatrician suggests a single bottle-feed at night – perhaps giving dad a turn? – for those mothers who are breastfeeding. More conclusive studies will be needed to provide a definite recipe, he says.

The surprising results emerged when Katz, of TAU’s Department of Pediatrics, Sackler Faculty of Medicine and his colleagues set out to discover whether CMA was accompanied by an allergy to soymilk as well.

“We weren’t even looking for a risk factor,” he says, adding that they found no link between cow’s milk and soy allergies, despite previous evidence that had proposed such a link. “Soy is still a reasonable feeding alternative for children with cow’s milk allergy,” according to Katz.

Overturning traditional recommendations

The TAU study was reported in a recent issue of the Journal of Allergy and Clinical Immunology ת שמג provides invaluable information for lactation specialists, and possibly for the World Health Organization, which currently recommends that a woman switch from breast to bottle at the three-to-five month period.

It is exactly this period that Katz found to be the worst time to expose a baby to cow’s milk. If not exposed earlier, he suggests waiting until the child is one year old to introduce cow’s milk into the diet.

The study also provides the most conclusive results on the incidence of allergy to cow’s milk protein in babies and children. In a given population, the rates of allergy are still quite high -0.5% in Katz’s estimation – but much lower than the two-to-four percent documented in other literature.

While further research is needed to determine how early feeding of cow’s milk could protect a child from the common cow’s milk allergy into the teen and adult years, in the meantime Katz suggests a feed of high-quality formula every night after birth.

Email Newsletter icon, E-mail Newsletter icon, Email List icon, E-mail List icon Sign up for our Email Newsletter

For Email Marketing you can trust

More on Health

Fighting for Israel's truth

We cover what makes life in Israel so special — it's people. A non-profit organization, ISRAEL21c's team of journalists are committed to telling stories that humanize Israelis and show their positive impact on our world. You can bring these stories to life by making a donation of $6/month. 

Jason Harris

Jason Harris

Executive Director

Read more: