Q: What causes little babies to have gas and how can you get rid of it?
A: Babies acquire gas in two ways -- they swallow air, and produce it as a byproduct when they digest food. In either case, gas usually passes quite easily from the mouth as a burp or from the rectum, causing the baby little or no discomfort. Parents and grandparents tend to blame gas for a baby's discomfort much more than it deserves.
Some air-swallowing is a normal part of feeding both bottle- and breast-fed babies. That is why "burping" is recommended at intervals during feeding. Babies should be burped by holding them so the gas will rise to the top of the stomach and be able to escape into the throat. Good positions are upright against your shoulder or seated on your lap. Tap the baby's back gently to encourage gas bubbles to come up. If your baby seems to have lot of gas, burp more frequently. You can help a bottle-fed baby avoid swallowing air by holding the bottle on an angle that keeps the nipple filled with liquid.
What you feed your baby also is important. When the human body cannot digest food, it remains in the intestine and is attacked by the bacteria that live there. Gas is formed when the bacteria break down the food and is a byproduct of the work of those bacteria.
Human milk and formula are composed of substances that are more easily and completely digested than are "solid" foods. If your baby is troubled by gas it may be that you have introduced additional foods too early. Ask your baby's doctor.
We are curious why you have asked about gas. In our experience this question usually arises when a baby has colic. Because a colicky baby cries frequently, it swallows a lot of air. It may appear to parents this "gas" is the cause of the crying when it's really the result. If you asked about gas because your baby is crying more than you think he should, call your baby's doctor for help.
Dr. Wilson is director of general pediatrics at the Johns Hopkins Children's Center; Dr. Joffe is director of adolescent medicine.