Clinical Question: Can a reduction in allergens in the diet of a breastfeeding mother decrease colic?

Setting: Outpatient (primary care)

Study Design: Randomized controlled trial (single-blinded)

Allocation: Concealed

Synopsis: Because changing an infant’s diet does not affect colic, the researchers conducting this study focused instead on changes in the diet of breastfeeding mothers. They recruited 107 infant and mother pairs in which the mother was exclusively breast-feeding. The infants were younger than six weeks and had colic symptoms. The infants were full term with an uneventful perinatal history, and the colic had begun an average of three weeks after birth. Crying and fussing were documented for more than 10 hours in a 48-hour period.

The children and mothers were assigned, using concealed allocation, to a diet high or low in allergens. Mothers in the low-allergen group were asked to exclude all dairy products, soy, wheat, eggs, peanuts and other nuts, and fish from their diet and were given a powdered rice-based drink and rice bread. Mothers assigned to the high-allergen group were given a soy and cow’s milk powder mixture to make a milk drink and were given peanuts, wheat, and a chocolate muesli bar to eat daily. Neither group of mothers was told the purpose of the study. Mothers recorded their diet and infant crying and fussing behavior on previously validated charts after seven days on the new diet. The primary outcome, a 25 percent reduction in crying and fussing duration, occurred in 74 percent of the infants in the low-allergen group and in 37 percent of the high-allergen group (number needed to treat = 2.7; 95% confidence interval, 1.78 to 5.56). However, similar proportions of children in both groups (63 and 72 percent, respectively) still had colic as defined by a crying and fussing duration of at least six hours over a 48-hour period. Also, there was no difference between the two groups in the mothers’ overall impressions of their children’s response to treatment.

Bottom Line: Young breastfed infants (six weeks of age) with pronounced colic will respond to a decrease in allergens in their mothers’ diets, with 74 percent of them decreasing the time spent crying or fussing by at least 25 percent. However, most of the children will still meet the definition of colic. (Level of Evidence: 1b)