Tummy gas

Why does my baby have gas?

Gas collects in the stomach and bowels for various reasons. Babies swallow air when they feed, and bacteria in the bowel produce gas when they act on the stool. The resulting gas can stretch the stomach and bowels, causing pain. The gastrocolic reflex, or cramping of the bowels needed to move the gas and stool can produce noise and more pain. In either case, putting the baby against the mother’s upper chest and shoulder and massaging the baby’s back can ease the pain.


A) The origin of gas

Gas in the baby's tummy has two sources:

  1. Babies swallow air when they feed, although breastfed babies generally do not swallow a lot (Gridneva 2016; McClellan 2010).
  2. In the bowel, bacteria produce gas by acting on the stool (poop).

Gas is generally not caused by the mother’s diet or by her drinking soda (fizzy) drinks.

B) The effect of gas

Gas can stretch the stomach and bowels causing pain, and the cramps (the gastrocolic reflex) needed to move the gas out of the baby's system cause noise and further pain. 

These signs are normal and show that the baby is getting enough milk. They are more pronounced when the mother has a large milk supply and the baby is growing quickly. They settle over time.

Normal babies have large tummies. This is not caused by gas.

C) Managing gas

Normal babies will burp and pass gas regularly to rid themselves of it.

When a baby has a lot of tummy pain, it is difficult to tell whether the pain is from air in the stomach or bowels or from bowel cramps. Fortunately, putting the baby against the mother’s upper chest and shoulder and massaging the baby’s back (burping techniquefixes both by helping the baby burp and by decreasing the pain as the bowel bowel cramp works its way along.

Prescription medication and over-the-counter products have not been shown to make babies any happier.  

Infant formula manufacturers often advertise that their brand reduces gas. There is very little evidence that is the case. Furthermore “low gas” brands often replace normal milk sugar (lactose) with much sweeter tasting corn syrup solids or table sugar.


Gridneva Z, Kugananthan S, Hepworth AR, et al. Effect of human milk appetite hormones, macronutrients, and infant characteristics on gastric emptying and breastfeeding patterns of term fully breastfed infants. Nutrients. 2016 Dec 28;9(1). pii: E15

McClellan HL, Sakalidis VS, Hepworth AR, et al. Validation of nipple diameter and tongue movement measurements with B-mode ultrasound during breastfeeding. Ultrasound Med Biol. 2010 Nov;36(11):1797-807