What Is Colic?
What does the term actually mean? Not much, it turns out. Dozens of theories -- some of them mutually contradictory -- have been advanced to account for the excessive crying we call colic, including gas, lactose intolerance, maternal smoking, reflux, low birth weight, maternal stress, protein allergy, bottlefeeding, over- and under-stimulation, and any number of gastrointestinal disorders. Any of these could explain baby's crying, as could hunger, a room kept too hot or cold, or a need to be held.
But none account for more than a small percentage of cases of excessive crying. Nor do any explain the cyclic pattern of such crying -- the fact that serious bouts tend to occur in late afternoon or early evening. In fact, a growing body of research suggests that colic is not an illness or syndrome but merely the high end of normal crying.
The mystery began to unravel back in the 1960s, when T. Berry Brazelton, MD, founder of the Child Development Unit at Children's Hospital Boston, identified a universal infant crying curve that accounts for all crying in the first few months of life, including so-called colic. In subsequent studies, Ronald Barr, MDCM, professor of pediatrics at the University of British Columbia, in Vancouver, demonstrated that infant crying begins at about 2 weeks of age, increases until it peaks at about 6 weeks, then gradually decreases until it stabilizes at 3 or 4 months. Dr. Barr, the lead editor of Crying as a Sign, a Symptom & a Signal (Mac Keith), also noted that crying tends to be clustered in late afternoons, particularly at the 6-week peak period.
In other words, normal crying and colic follow exactly the same developmental pattern. The difference is one of degree, not kind. Although crying manifests itself as full-fledged howling in one baby and mild fussing in another, each is simply one side of the same developmental coin. The observation of clinicians supports this research. "Colicky babies cry no more frequently than other babies," says Henry Bernstein, MD, associate chief of general pediatrics at Children's Hospital Boston, "but each episode is longer and more intense."