Babies bite their lower lip for a handful of predictable reasons, and most of the time the habit resolves on its own. The key is figuring out what’s driving the behavior, whether it’s teething pressure, self-soothing, hunger cues, or simple exploration, and then redirecting it before it becomes a lasting oral habit. Here’s what’s behind it and what actually works.
Why Babies Bite Their Lower Lip
The most common trigger is teething. Babies instinctively bite and gnaw on things because counter-pressure against the gums relieves the discomfort of teeth pushing through. When there’s no teether or toy handy, the lower lip becomes the easiest target. If you notice the biting alongside drooling, fussiness, or swollen gums, teething is the likely culprit.
Outside of teething, lip biting often starts as a variation of the sucking reflex. Babies are born with a strong drive to suck, and when that reflex doesn’t get fully satisfied through feeding, they may latch onto their own lip instead. This is more common in babies who switch frequently between breast and bottle or who spend time with caregivers using different feeding methods. The lip provides familiar, comforting pressure that mimics nursing.
Stress and anxiety can also play a role, even in very young babies. Changes in routine, overstimulation, or separation from a primary caregiver can prompt lip sucking or biting as a self-soothing mechanism. And sometimes a baby is simply exploring. In the first year, the mouth is one of the primary ways infants learn about the world, including the parts of their own body they can reach.
When It Becomes a Concern
Occasional lip biting in infancy is normal and not something to worry about. The habit becomes worth addressing if it’s constant, causing visible irritation or sores on the lip, or persisting well past the teething stage. Pediatric dental guidelines recommend discouraging non-nutritive sucking habits by age 2, with the goal of stopping them entirely by age 3. Beyond that point, persistent oral habits like lip sucking are linked to dental alignment problems, including open bite (where the front teeth don’t meet), crossbite, and changes to how the upper and lower jaw relate to each other.
For babies and young toddlers, though, the focus should be on gentle redirection rather than active correction. The habit is developmentally appropriate at this stage, and putting too much attention on it can sometimes reinforce it.
Practical Ways to Redirect the Habit
Offer the Right Teether
If teething is behind the biting, give your baby something better to chew on. Look for teethers with varied textures, some smooth and some ridged, since the textured surfaces provide the kind of sensory input that makes lip biting satisfying in the first place. Chilled (not frozen) teethers add a mild numbing effect that further relieves gum pressure. Keep one within reach during the times your baby bites most, whether that’s during play, in the car seat, or before sleep.
A clean, cold washcloth works well in a pinch. The fabric gives a different chewing sensation than silicone, and some babies prefer it.
Check Feeding Patterns
Babies who aren’t getting enough sucking time during feeds sometimes compensate with lip biting afterward. If you’re bottle-feeding, make sure the nipple flow isn’t too fast, which can shorten feeding sessions and leave the sucking urge unsatisfied. Allowing your baby to pace their own feeding, with breaks and slower flow, gives the sucking reflex more time to do its job. For breastfed babies, letting them stay at the breast for comfort nursing after the feeding itself can help.
Gently Break the Pattern
When you notice your baby biting their lip, calmly remove the lip from between their gums with a clean finger and offer a pacifier, teether, or your finger to chew on instead. Don’t make a big reaction. A neutral, quiet redirect teaches the baby there’s a better option without turning the lip biting into an attention-getting behavior. Over days and weeks, this consistent swap builds a new habit.
Address Comfort and Stimulation
If the biting seems connected to stress or boredom rather than teething, look at what’s happening in the environment. A baby who bites their lip mostly during transitions (being put down, moved to a new setting, handed to someone unfamiliar) may need extra soothing during those moments. Holding, rocking, or offering a comfort object can meet the same need the lip biting is trying to fill. For babies who bite out of boredom, increasing sensory play with safe mouthing toys, textured books, and age-appropriate chewable objects gives the mouth something productive to do.
Protecting the Lip From Irritation
Repeated biting can leave the lower lip red, chapped, or cracked. Lanolin cream, the same product breastfeeding mothers use for sore nipples, is a safe and effective barrier for a baby’s lips. It moisturizes and protects the skin, and it won’t harm your baby if they ingest a small amount. Apply a thin layer after feedings and before naps or bedtime, when the lip is most likely to dry out.
Avoid medicated lip balms, products with fragrances, or anything containing camphor or menthol. These can irritate a baby’s sensitive skin and are not safe if swallowed. Plain lanolin or a small amount of petroleum jelly are the safest choices. If the lip develops open sores that don’t heal within about two weeks, looks infected (swelling, pus, or spreading redness), or your baby develops a fever alongside the irritation, have your pediatrician take a look.
What to Expect Over Time
Most babies stop biting their lower lip once the underlying cause passes. Teething-related biting naturally decreases after the most intense phase, typically between 6 and 16 months as teeth come in waves. Self-soothing lip habits tend to fade as babies develop other coping skills: talking, using a lovey, or finding new ways to manage big feelings.
If the habit sticks around past age 2 and your child is biting or sucking their lip frequently throughout the day, bring it up at a dental visit. A pediatric dentist can check whether the habit is affecting tooth alignment and recommend next steps. In most cases, a combination of positive reinforcement and gentle reminders is enough to phase it out. Oral appliances, like lip bumpers, exist for older children with deeply ingrained habits, but they’re rarely needed and wouldn’t be considered until well past toddlerhood.
The short version: for babies, redirect consistently, keep the lip moisturized, and give the mouth plenty of safe things to explore. The habit is almost always a phase, and one your baby will outgrow with a little help.