Thumb-sucking is a habit that’s hard to break for many babies and toddlers. “The first addiction” can become a real problem if you don’t address it at the right time. Hopefully, after you read about these three reasons why babies and toddlers suck their thumbs, you’ll better understand your baby’s perspective and what you can do to guide them to a healthier, more productive future.

1. Thumb-Sucking Is a Natural Reflex

It may surprise parents to learn that many of their newborn’s actions are natural reflexes, not conscious movements. For example, in order to breastfeed properly, babies are born with an innate ability to search for and cling onto nipples. These same rooting and sucking reflexes are at the center of why some babies and toddlers suck their thumbs. They’re repeating the same reflexes they know instinctively.

2. It Has a Calming Effect

Thumb-sucking, often referred to as the “first addiction,” earns the title because it helps infants relieve stress wherever they are; young children can always turn to their own reflex to keep them calm. This is among the primary reasons why babies and toddlers suck their thumbs. In the short term, this addiction has its benefits. It relieves stress, which lowers the likelihood that the child will become sick.

However, children should not continue to suck their thumbs past age five. Once they have gone beyond that age, it becomes more likely that the thumb-sucking will damage their teeth. Then you need to consider how to stop the thumb-sucking habit.

3. It’s a Sleep Aid

Many thumb-suckers enjoy the habit most intensely while they sleep. Since thumb-sucking provides a soothing affect, babies and toddlers often unconsciously practice the habit as they drift off to dreamland. For these babies, the calming properties of thumb-sucking are so powerful that it brings them to rest.