Newborns are gassy because their digestive systems are brand new and still learning how to process food and move gas through the intestines. Nearly every newborn deals with noticeable gas in the first few months of life, and in most cases it’s completely normal. Your baby’s gut is colonizing with bacteria, their abdominal muscles are weak, and they swallow air every time they eat or cry. All of this adds up to a squirmy, grunting, sometimes very unhappy baby.
Their Digestive System Is Still Developing
When your baby drinks milk, some of it passes through the intestines without being fully digested. The bacteria that naturally live in the gut feed on that undigested milk and produce gas as a byproduct. This is the same process that happens in adult digestion, but newborns are far less equipped to handle it.
The gut’s bacterial community, known as the microbiome, doesn’t reach a stable, adult-like state until around age 3 to 5. In those early weeks and months, the bacterial population is shifting rapidly. New species are moving in, and the balance between gas-producing and gas-consuming bacteria hasn’t been worked out yet. That instability means more gas production than your baby’s system can efficiently clear.
On top of that, newborns can’t do what you do when you feel gassy. They can’t shift positions, bear down effectively, or coordinate their abdominal muscles to push gas out. They’re essentially stuck, which is why they often look uncomfortable and strain even when nothing is wrong. They’re also not accustomed to the sensation of gas moving through their intestines, so it can genuinely startle or upset them.
Air Swallowing During Feeds
Every feeding session is an opportunity for your baby to swallow air, and that air has to go somewhere. Babies swallow air when they latch onto the breast or bottle, when they cry before a feed, and when they pause to breathe mid-feed. This is called aerophagia, and it’s the most controllable source of newborn gas.
Latch quality matters a lot. A shallow or disorganized latch, whether on breast or bottle, breaks the seal around the nipple and lets air slip in with each swallow. Babies with tongue tie or lip tie are especially prone to this because the restricted tissue prevents them from forming a tight seal. If your baby clicks or pops off the breast frequently, or if you hear a lot of gulping sounds, they may be taking in extra air.
Bottle-fed babies tend to swallow more air than breastfed babies, particularly if the bottle nipple flow is too fast or too slow. A flow that’s too fast forces the baby to gulp, while one that’s too slow makes them suck harder, pulling in air around the nipple. Paced bottle feeding, where you hold the bottle more horizontally and let the baby control the pace, can reduce air intake significantly.
Burping Isn’t Always Enough
Burping releases air trapped in the stomach, but not all gas sits in the stomach. Gas produced by bacterial digestion forms lower in the intestines, and no amount of burping will reach it. That’s why your baby can burp well after a feed and still be gassy an hour later. The two types of gas, swallowed air and bacterially produced gas, require different strategies.
For swallowed air, burp your baby during and after feeds, not just at the end. Try different positions: over the shoulder, sitting upright on your lap with chin supported, or lying face-down across your legs. Some babies burp easily in one position and not another.
For intestinal gas, gentle movement is your best tool. Bicycle legs (slowly pedaling your baby’s legs while they lie on their back) helps move gas through the lower intestines. Tummy time, even just a few minutes at a time, puts gentle pressure on the belly. You can also try laying your baby face-down along your forearm, sometimes called the football hold, which combines warmth and pressure in a way many gassy babies find soothing.
What About Your Diet?
If you’re breastfeeding, you’ve probably been told to avoid broccoli, beans, garlic, onions, or spicy food. The evidence behind this advice is thin. There is limited scientific research proving that specific foods in a breastfeeding parent’s diet cause intestinal issues in their babies. Spicy foods in particular have not been shown to cause discomfort in breastfed infants. Many parents report that foods like kale, beans, or peppers seem to make their baby gassier, but many other babies tolerate those same foods without any issues.
The compounds that make you gassy from cruciferous vegetables (fiber and certain sugars) are broken down in your own gut. They don’t pass into breast milk in a form that would produce gas in your baby. That said, if you consistently notice your baby is more uncomfortable after you eat a specific food, there’s no harm in temporarily cutting it out to see if things improve. Just don’t restrict your diet broadly based on a list you found online.
Do Gas Drops Work?
Over-the-counter gas drops containing simethicone are widely marketed for infant gas, but the evidence that they work is not strong. Studies on simethicone for colic, which involves excessive crying often attributed to gas, suggest it performs no better than a placebo. Pediatricians are increasingly recommending that parents skip gas drops altogether rather than spending money on something with no proven benefit.
Probiotics are a different story, at least for breastfed babies. One well-studied probiotic strain, Lactobacillus reuteri, showed meaningful results in a randomized trial of breastfed infants with colic. Babies given the probiotic cried and fussed for a median of 60 minutes per day by the end of the three-week study, compared to 102 minutes per day in the placebo group. Total fussing time over the full study period dropped by roughly 20%. These results are specific to breastfed infants; similar data for formula-fed babies isn’t available from the same research. If you’re considering a probiotic, look for one specifically formulated for infants that contains this strain.
When Gas Might Signal Something Else
Normal newborn gas comes and goes, doesn’t prevent your baby from eating, and doesn’t cause weight loss or other concerning symptoms. Certain patterns, though, suggest something beyond typical digestive immaturity.
Cow’s milk protein allergy is one of the more common culprits when gas seems excessive and persistent. It affects a small percentage of infants and can occur even in exclusively breastfed babies (since cow’s milk proteins from a parent’s diet pass into breast milk). The key difference from normal gas is the presence of additional symptoms: loose stools that may contain blood or mucus, vomiting, skin rashes or hives, and persistent distress that goes beyond typical fussiness. Some reactions appear within minutes of feeding, while others develop over several hours, making them harder to connect to a specific trigger.
If your baby is gaining weight normally, eating well, producing plenty of wet and dirty diapers, and has stretches of contentedness between gassy episodes, their gas is almost certainly a normal part of being a newborn. Most babies show noticeable improvement by 3 to 4 months of age as their digestive coordination matures and their gut bacteria stabilize. Until then, bicycle legs, good burping technique, and patience will get you through the worst of it.