What Is The Thing That Babies Put In Their Mouth

Why Babies Put Everything in Their Mouths

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on October 13, 2021

It may seem gross to you, but mouthing is a normal part of your baby's development.

Favorite blankie, rubber ducky, board book, fuzz on the rug, yesterday's cereal on the floor — you name it, it's likely been in your baby's mouth. Welcome to baby mouthing, a completely normal part of your child's development (as unpleasant as it may seem).

When do babies start mouthing?

Babies typically start mouthing by 4 months, once they're able to bring their hands to their mouths and suck on their fingers. At 6 months, this habit kicks into overdrive, and your little one will start mouthing just about anything she can grab.

As cringe-inducing as it is to watch your baby eat a dust bunny off the floor, baby mouthing is a totally normal stage of development. If your baby isn't bringing her hands and other objects to her mouth by the age of 6 months, it's probably not a cause for concern, but mention it to your pediatrician just in case.

Why do babies put everything in their mouths?

The old way of thinking about an infant's everything-goes-in-their-mouth habit was that it was a key component of baby development — that mouthing is how babies learn about the world, one lick at a time.

And while that's true, some experts now think there's even more to mouthing. Here are just a few reasons babies put everything in their mouths.

Self-soothing

From the moment she's born, your infant is looking for ways to comfort herself when she's tired, uncomfortable or hungry. And once she discovers that her hands and fingers are, well, always on hand, she'll realize that she has a built-in way to soothe herself.

Exploring the world around them

As months go by, babies start to notice that their hands are useful tools for exploring new environments. You'll notice your little one start to swat, grasp and reach out for whatever's nearby — and once your baby can hold onto an object, she's guaranteed to put it in her mouth.

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Teething

Babies usually cut their first tooth around 6 months, although some little ones get their first tooth a few months earlier or later (sometimes even after 12 months). Before a tooth erupts, you may notice an increase in your baby's desire to stick everything in her mouth — and then chomp on it to ease the pain.

Possibly improving their immune system

When your baby picks something up off the ground — the pacifier that's been hanging out with the old Cheerios under the sofa, for example — and sticks it in her mouth, the bacteria and viruses she exposes herself to give her immune system a chance to fight them off — and makes your baby stronger.

In fact, one hypothesis is that babies who aren't exposed to enough bacteria, germs and animal dander may have an increased risk of allergies and asthma. While that doesn't necessarily mean you should neglect all cleaning duties, the good news is that you don't have to worry too much about all those old Cheerios.

Safety tips for a baby who is mouthing everything

Regardless of why your baby puts everything in her mouth, know that certain items should be off-limits. Most importantly, choking hazards like coins, buttons and marbles, plus anything that's covered in lots of germs (think kitchen sponges and cell phones) that could be harmful to your baby or make her sick.

While babies tend to have a good gag reflex, it's not foolproof. Use these tips to keep your baby safe:

Remove choking hazards. Patrol the rooms in your home — especially baby's room and playroom — for small items that could be a choking hazard. Remove anything small enough to fit all the way inside your baby's mouth (think beyond an older child's toys with small parts; also consider toys like marbles, dice and balloons, as well as household items like plastic bags, buttons, hair ties and small batteries).
Keep anything poisonous out of reach. Babies don't know what's safe and what isn't — it's all fascinating to them. So put anything that's potentially poisonous — like medicine, nail polish, cleaning products, house plants, bug spray, markers, wine, e-cigarettes, soaps and detergents — out of reach and out of sight.
Put away items that pose suffocation or strangulation risks. Everyday household items like power cords, yarn and the cords on blinds can carry a risk of suffocation or strangulation to your little one if she uses it for mouthing. Secure these objects or store them locked up high and out of baby's reach. Even baby items, like baby blankets, stuffed toys, bibs, pacifier clips and baby headbands pose a risk if used unsupervised.
Look out for old food. That stale piece of cereal that was on the kitchen floor a second ago and is now in your baby's mouth is probably okay. But food that's spoiling (or ready to — like the food in the dog's bowl) isn't safe because those bacteria could make your baby sick. Another concern: food that falls onto a damp or wet area (bacteria multiply more rapidly on wet surfaces) or food that's been mouthed and then left behind.
Provide a safe mouthing zone. Encourage your baby's mouthing habit by giving her access to safe objects like teething toys. Just stay away from hazards like amber bead teething necklaces, which have not been found to work and can be unsafe.
Keep it clean. If there's an old crumb on the floor, baby will find it, so consider sweeping or vacuuming areas where she plays on the floor regularly to keep her from mouthing on unsavory items that have been left behind. And don't let your baby play with germ-ridden objects like your dog's favorite chew toy.

Bottom line? While you should keep anything unsafe away from your baby, accept that no matter what, your baby will mouth things you never would — at least, not since you were an adorable mouthing infant yourself!

Make a good-faith effort to keep things basically clean — think "clean enough," not "pristine" — and to prevent your baby from doing something that could put her in harm's way. You and your little one will be better for this straightforward (and relatively easygoing) attitude.

From the What to Expect editorial team and Heidi Murkoff, author ofWhat to Expect When You're Expecting. What to Expect follows strict reporting guidelines and uses only credible sources, such as peer-reviewed studies, academic research institutions and highly respected health organizations. Learn how we keep our content accurate and up-to-date by reading our medical review and editorial policy.

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