Feb. 1, 2000 (Los Angeles) -- Colicky babies respond well to formulas consisting of protein fragments rather than whole proteins, according to two new studies in Acta Paediatrica. "Both papers strengthen the thought that colic may be due to dietary factors," co-researcher Anthony Kulczycki Jr., MD, tells WebMD.
Colic is a syndrome that affects about 20% of infants in the first months of life. The infants are irritable and fussy, and they cry inconsolably. The cause is unknown, but studies have pointed to elements in the diet.
In their paper, Kulczycki, an associate professor of medicine at Washington University School of Medicine in St. Louis, and his colleague, studied six healthy male infants diagnosed with moderate to severe colic -- at least 3 hours per day of fussing or crying for at least 2 weeks. The babies were between three and seven weeks of age when they entered the study.
After a three- to six-day evaluation period, the infants received a formula called Neocate (SHS North America), which is based on amino acids, the basic components of protein They received the formula for at least five and as long as 17 days. At the end of that period, the authors fed the babies small amounts of cow's-milk protein to see if the symptoms returned.
In the second study, conducted by I. Jakobsson, MD, and colleagues in Sweden, 22 infants with severe colic (crying seven-and-a-half hours per day) were fed two different formulas, Alimentum (Abbott Laboratories) or Nutramigen (Mead Johnson Nutritionals), in which the protein molecules had been only partially broken down. The researchers were comparing both formulas' effect on colic.
The babies received one formula for 7 days and were then switched to the other formula for another 7 days. On days 15, 18, and 21 the investigators gave them two forms of cow's-milk protein and a placebo, in random order.
In both studies, most of the infants tolerated the formula well and improved, usually within one to two days. Alimentum and Nutramigen were found to be equally effective. Also in both studies, the infant's colicky symptoms returned when "challenged" with the cow's milk or bovine protein.
Colic is a common symptom "that encompasses a large number of underlying diagnoses," says Clifton Furukawa, MD, head of pediatric allergy at the University of Washington School of Medicine in Seattle. He estimates that milk intolerance causes at least 8% of cases, although no one knows for sure.
However, according to Sajjad Yacoob, MD, a pediatrician at Children's Hospital of Los Angeles, milk-protein intolerance by definition is not colic. "Mostly colic is something that we haven't been able to define yet. What [these investigators] may have done is just treated a milk-protein intolerance." Neither Furukawa nor Yacoob were involved in either study.
Yacoob, who is also an assistant professor of pediatrics at the University of Southern California-Keck School of Medicine in Los Angeles, reassures parents that colic, although nerve-racking, does no lasting damage to the baby.
Often children respond well to movement, such as riding in a car or even being placed on top of a washing machine. Nursing mothers might eliminate cow's milk or gassy foods from their diets, since compounds in these products may enter their milk.
Should these measures fail "we know that [these formulas] will work in a defined set of kids, but we recommend that people check with their pediatricians before trying them," says Kulczycki.
All of the products used in these studies are FDA-approved and contain all the nutrition growing babies need, he adds. However, they are expensive: the amino-acid formula, for example, costs approximately $50 for a 14-ounce can of powder, which lasts two to three days for an average infant. On the other hand, "What's the cost of a decent night's sleep and good interaction with your child for a few weeks?"
Alimentum and Nutramigen are available in selected grocery stores, pharmacies or can be ordered from their respective manufacturers. Neocate must be ordered from a pharmacist or directly the manufacturer.
- Two new studies suggest complete proteins given to babies can contribute to colic.
- Colicky babies tolerated formulas of fragmented protein and improved, but feeding them cow's milk led to return of colic symptoms.
- Observers interpret the studies differently, noting either that colic may be due to dietary factors or that the researchers simply treated a milk-protein intolerance.