Babies have a tendency to use their mouth in a variety of ways. If you notice your baby frequently sticking their tongue out, you may wonder whether this is a normal behavior. The short answer is yes; sticking the tongue out is typically a totally normal infant behavior.

Babies are born with a strong sucking reflex and instinct for feeding. Part of this reflex is the tongue-thrust reflex, in which babies stick their tongues out to prevent themselves from choking and to help latch on to the nipple.

Using their mouths is also the first way babies experience the world. It’s very common for them to mouth things and stick out their tongues, both as part of the feeding instinct and exploring the new world around them. Part of this behavior is your baby noticing the feel of his or her own lips.

If you find that your baby’s tongue is always sticking out of their mouth, or they seem to be constantly drooling — more than is normally associated with spit-up and teething — or they have difficulty swallowing, call your doctor.

That said, here are 10 causes, some common and some rare, for a baby to stick his or her tongue out.

There has been some debate since the 1970s about whether newborn babies imitate adult behavior.

Older babies certainly mimic, but several studies, including one in the Journal of Developmental Science, have reported that babies as young as a few weeks old imitate adult facial expressions, including sticking out their tongues.

The tongue-thrust reflex that babies are born with includes sticking the tongue out. This helps facilitate breast or bottle feeding.

While this reflex typically disappears between 4 to 6 months of age, some babies continue to stick their tongues out from habit. They may also simply think it feels funny or interesting.

Crying is not the only way that babies communicate they are hungry. Crying is actually a late sign of hunger.

According to the Centers for Disease Control and Prevention (CDC), early signs of hunger may include clenched hands, putting hands in the mouth, turning toward the breast or bottle, and smacking or licking the lips. Sticking the tongue out may be part of a baby’s hunger cues.

Babies may also stick their tongues out when they are full. Other signs of fullness may include turning the head away, spitting out food or milk, and simply refusing to suck or eat.

If a baby has a larger than average tongue, a condition known as macroglossia, they may stick their tongue out more than usual.

Macroglossia may occur because of genetics, or abnormal blood vessel or muscle development in the tongue. It may also be caused by conditions such as hypothyroidism or tumors.

Macroglossia may occur as one symptom in syndromes such as Down syndrome and Beckwith-Wiedemann syndrome.

If your baby’s tongue does not seem to fit into their mouth, or you notice other concerns, such as excessive drooling, difficulty swallowing, poor muscle tone, or difficulty feeding, call your child’s pediatrician to discuss your concerns.

There are a number of syndromes or conditions that may cause a baby to have a smaller-than-average mouth. Sometimes babies are genetically predisposed to have a small mouth.

One such condition is micrognathia, or a small jaw. Micrognathia may be genetic or part of a syndrome or condition such as cleft lip or cleft palate, Beckwith-Wiedemann syndrome, Pierre Robin syndrome, and several others.

Children with Down syndrome may have a number of signs including smaller-than-average mouths, short stature, distinct facial features, and decreased muscle tone.

Babies with a condition called DiGeorge syndrome may also have small mouths due to changes in the shape of the palate. DiGeorge syndrome has a number of other symptoms, including heart defects and developmental delay.

Some babies have decreased muscle tone. Since the tongue is a muscle, and is controlled by other muscles in the mouth, decreased muscle tone can cause the tongue to stick out more than usual.

Several conditions may cause decreased muscle tone, such as Down syndrome, DiGeorge syndrome, and cerebral palsy.

Babies typically breathe through their nose. If your baby has nasal congestion or large tonsils or adenoids, they may breathe through their mouth instead. This can cause the tongue to stick out.

If your baby seems to have difficulty breathing, flaring of the nostrils, wheezing, or other unusual breathing sounds, you should call your baby’s doctor immediately. If you have other ongoing concerns about your baby’s breathing or amount of congestion, call your baby’s doctor to help troubleshoot.

If your child has large tonsils or adenoids that are interfering with breathing or feeding, they may need to be surgically removed.

Some babies stick their tongues out when they are experiencing gas pains or passing gas. All babies pass gas as a normal part of digestion. Some babies react to the sensation more than others, and may cry, grimace, stick out their tongue, or even smile.

Occasionally, babies may have a mass or swollen gland in their mouth, which can force the tongue to protrude.

Very rarely, this may be some type of oral cancer. More commonly, they may have an infection that causes a salivary gland cyst.

If your baby seems to stick out their tongue more than usual, drools excessively, is fussy with eating or refuses to eat, or you can feel or see a bump in their mouth, call your child’s doctor.

Babies receive most of their nutrition for the first year of life from breastmilk or infant formula. The CDC, and most pediatricians, recommend adding solid foods, starting with pureed baby food or cereal, around 6 months of age.

The amount of solid food a baby eats gradually increases, until the age of 1 year, when most of their nutrients come from solid foods rather than milk alone.

Some babies take readily to solids, while others dislike the taste or textures and may take longer to become accustomed. If a baby is not ready for solid foods, they may stick their tongue out to push the food away or get it out of their mouths. They may not yet have the oral coordination necessary to eat solids.

If your baby is sticking their tongue out persistently when you try solid foods, perhaps stop and try again in a week or two. If you have concerns about your baby’s eating, speak with your baby’s doctor.

Babies stick their tongues out for a number of reasons. Most of the time, this is completely developmentally normal. Occasionally, a baby who sticks their tongue out more than usual may have an underlying reason.

If you are concerned about your baby sticking their tongue out or other accompanying symptoms, it may be helpful to speak to your baby’s doctor.