When a baby sticks their tongue out, they are usually doing something perfectly ordinary. They are exploring their mouth, responding to a face, showing they are hungry or pushing out a food they cannot yet swallow. It is a common gesture throughout the first year. It only becomes a medical matter if it comes with difficulty feeding, swallowing or closing the mouth.
This article looks at the known reasons, age by age, and at what research really says about newborn imitation. The picture is less clear-cut than you often read.
Why does a baby stick their tongue out?
Babies stick their tongue out for five main reasons. They are discovering their mouth and the sensations it produces. They are reacting to an adult’s face. They are looking for the breast or the bottle. They are pushing out a food offered too early. Later on, they are playing and communicating. These reasons follow on from one another and overlap over the months.
The tongue, a first tool for exploring
The lips and tongue are among the most sensitive areas of an infant’s body. In the first few months, the mouth is how they discover the world, long before the hands. Sticking the tongue out, pulling it back in, clicking it: these are ways of exploring, just like gazing at their own hands.
This exploration then extends to objects. At around 3 or 4 months, your baby brings whatever they grab to their mouth, and the tongue plays its part in this discovery. Our article on the baby who puts everything in their mouth describes this oral phase and how to keep it safe. It follows closely on from the age when babies start grasping objects.
Baby sticks their tongue out when you do: are they really imitating you?
This is the most debated question. In 1977, Andrew Meltzoff and Keith Moore published a famous study in the journal Science. In it, they described newborns copying facial gestures, including sticking out the tongue. The idea that imitation is present from birth then made its way into the textbooks.
A 2016 study challenges this finding
In 2016, Janine Oostenbroek and her colleagues published a longitudinal study in Current Biology. They tested 106 infants at 1, 3, 6 and 9 weeks, using eleven different gestures. Their conclusion: babies did not stick their tongue out any more when the adult stuck out theirs than when the adult opened their mouth or smiled. According to these authors, imitation is more likely to appear at around 6 months.
A reanalysis reaches the opposite conclusion
In 2017, Meltzoff and ten co-authors reanalysed the raw data from this study in Developmental Science. They found significant imitation of tongue protrusion at all four ages tested. The effects are modest, but consistent from one age to the next.
What to take away
The question remains open and researchers do not agree. Some newborns probably do respond to a stuck-out tongue, without this being imitation in the full sense of the word. For parents, what matters lies elsewhere: these face-to-face exchanges count, whatever their scientific interpretation. Intentional imitation, on the other hand, clearly develops over the first year, as our article on imitation in babies explains.
Hunger, waking and looking for the breast
In newborns, mouth movements often come with waking up. The tongue pokes out, the lips purse and the head turns towards the breast or the hand. These gestures are among the signs an infant uses to show they are ready to feed, before crying starts.
Watching for these signs lets you offer the breast or the bottle sooner and calmly. A stuck-out tongue on its own does not necessarily mean hunger, but together with other signs, it is often part of the picture.
Starting solids: when the tongue pushes the spoon away
When starting solids, many babies push the purée back out with their tongue. This is not a rejection of the taste. It is a protective reflex: the tongue pushes outwards whatever comes into the mouth. The US WIC programme describes this reflex as a protection against choking.
The same programme lists, among the signs that a child is ready for solid food, keeping food in the mouth without pushing it out with the tongue. The INSPQ (Institut national de santé publique du Québec, Quebec’s public health institute) gives other markers: around 6 months, sitting without support and good head control. A baby born prematurely is assessed according to their corrected age.
If your baby always pushes the spoon away, it can help to wait a few days before trying again. To put these stages in context, see our article on starting solids, then the one on the age when babies feed themselves with a spoon.
After 6 months: a game and the beginnings of language
In the second half of the year, babies often stick their tongue out for fun. They make mouth noises, bubbles and blow raspberries. They watch for the adult’s reaction and do it again if it gets a laugh. These mouth games train the muscles that will later be used to articulate.
Towards the end of the first year, a stuck-out tongue sometimes becomes a real message: a funny face, a way of saying no or a playful bit of cheek. It is part of the development of communication, described in our article on language development.
Teething
When a tooth is on its way, some babies dribble more, chew on everything and move their tongue a lot. They are exploring the swelling gum. This behaviour disappears once the tooth has come through. A suitable object to chew on can bring relief; the safety criteria are set out in our guide to the teething ring.
When should you worry if your baby sticks their tongue out?
In the vast majority of cases, there is nothing to do. Medical advice is warranted when the tongue stays out of the mouth almost all the time. It is also warranted when the tongue looks large or when your baby struggles to close their lips.
Other associated signs are worth mentioning to your doctor or to the PMI (Protection maternelle et infantile, the French mother and child health service):
- repeated difficulty sucking, latching on to the breast or swallowing;
- insufficient weight gain;
- very heavy, constant dribbling outside of teething;
- a baby who seems very floppy or has low muscle tone;
- noisy breathing during sleep.
Conversely, a tongue that never goes past the gums, along with painful breastfeeding for the mother, may suggest a tongue-tie. Here again, an examination by a professional is what settles it.
Should you stick your tongue out back?
Yes, if you both enjoy it. Stick your tongue out, wait, let your baby respond: it is a turn-taking game, just like swapping babbles. Position yourself about 20 to 30 cm from their face, move slowly and give them time. If they turn their head away, they need a break.
Key takeaways
- Babies stick their tongue out to explore, respond to a face, look for a feed, push food away or play.
- Whether newborns imitate tongue protrusion is still debated: a 2016 study challenges it, a 2017 reanalysis supports it.
- When starting solids, a tongue pushing the spoon away is a reflex, not a refusal.
- Medical advice is needed if the tongue stays out of the mouth all the time or if there is difficulty feeding or swallowing.
Sources
- Meltzoff A. N., Moore M. K., “Imitation of facial and manual gestures by human neonates”, Science, 198, 75-78 (1977).
- Oostenbroek J. et al., “Comprehensive longitudinal study challenges the existence of neonatal imitation in humans”, Current Biology, 26, 1334-1338 (2016).
- Meltzoff A. N. et al., “Re-examination of Oostenbroek et al. (2016): evidence for neonatal imitation of tongue protrusion”, Developmental Science, 21(4), e12609 (published online 27/09/2017).
- British Psychological Society, Research Digest, “Classic finding about newborn babies’ imitation skills is probably wrong” (20/05/2016).
- INSPQ, Mieux vivre avec notre enfant, “Quand introduire les aliments ?” (updated 17/02/2026).
- WIC Health (WIC programme, United States), “Ready to start solid food? Look for these 5 signs”.
