Infants explore the world with their mouths.

Why Do Infants Put Everything They See in Their Mouths?

by Jonae Fredericks

Babies are considered infants from birth to age 12 months. When these bundles of joy are not eating or sleeping, they are examining their hands and feet, tuning in to sounds and following objects with their eyes. And when they are not making gurgling and cooing sounds with their mouths, they are putting things in it. In fact, it seems infants put just about everything in their mouths.


The combination of grasping and mouthing goes hand-in-hand in the world of an infant. The act of reaching for an object, grasping it and then putting it in his mouth is one method that he uses to learn about the world around him. The University of Illinois at Urbana-Champaign website explains that infants mouth different objects in an effort to determine dimensions. Infants may twist and manipulate an object several times during the exploration process. Furthermore, size determines how the infant grabs and holds onto the object prior to putting it in her mouth.

The Shine Factor

Recent research shows that shine may be a factor in why infants put things in their mouths. According to Science Today at the University of California, babies appear drawn to glossy objects and those with reflective qualities. University of California psychologist Richard Coss theorizes that the attraction may date back to early primates and their search for water that was crucial to their survival. Presented with one shiny object and one dull object, infants are more likely to mouth the shiny object.


Research is ongoing, but studies discussed on the U.S. National Library of Medicine website suggest that mouthing may influence vocalization in infants. In fact, the times in an infant’s life when mouthing is at its peak appears to coincide with the development and production of consonants. Vocalization also appears to occur more frequently when an infant places an object in his mouth than when he is mouthing his hands and fingers. In their search for information about themselves and the world around them, mouthing seems to be an opportunity for infants to investigate their own voice.


Knowing that infants put everything in their mouths is reason enough to make sure their environment is as safe as possible during exploration. The University of Georgia website suggests making sure that toys and floors are clean at all times. Hard surfaces in the home and non-porous toys can be sanitized with a solution of 1 cup of bleach for every 5 gallons of water. Plastic bags and other dangerous objects -- as well as any toys that contain small pieces that may present a choking hazard -- should always be out of an infant’s reach.

About the Author

Jonae Fredericks started writing in 2007. She also has a background as a licensed cosmetologist and certified skin-care specialist. Jonae Fredericks is a certified paraeducator, presently working in the public education system.

Photo Credits

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