Why do newborns make “mm-mm” sounds while sleeping?
May 15, 2022
Source: Cainiu Health
Dr. Xie Zixing
Introduction
One possible reason why your baby frequently makes “mm-mm-mm” sounds while sleeping is that the infant’s body may be lacking certain essential nutrients. Babies’ primary foods—such as breast milk and infant formula—are highly nutritious, yet even these cannot supply *all* necessary nutrients. If this is the case—and provided the baby’s gastrointestinal system is mature enough to digest solid foods—we recommend introducing a varied and nutritionally balanced diet.
In families with children, every movement or behavior of the child can unsettle the entire household. Due to their young age, incomplete physical development, and heightened vulnerability to injury, infants require constant adult supervision—leading many to experience poor sleep quality. For instance, some babies make “mm-mm” sounds while sleeping. So why do newborns emit such sounds during sleep?
Why Do Newborns Make “Mm-Mm” Sounds While Sleeping?
One possible reason babies frequently make “mm-mm” sounds during sleep is a nutritional deficiency. Infants primarily consume breast milk or infant formula—both highly nutritious, yet neither provides *all* essential nutrients. If this is suspected, and the baby’s gastrointestinal system is mature enough for diverse foods, we recommend introducing a nutritionally balanced and varied diet.
Beyond nutritional factors, discomfort during sleep may also stem from overfeeding before bedtime—a concern many parents overlook. They often allow infants to eat as much as they wish, without adequately considering whether the child’s immature digestive system can handle it. Toddlers lack awareness that overeating harms their health; they simply continue eating until full. Though discomfort may not be apparent immediately, it often manifests later—during sleep.
In fact, numerous other factors can disrupt an infant’s sleep—such as the urge to urinate or unpleasant odors in the sleeping environment. Regardless of the cause, parents should remain calm and thoughtfully assess daily routines and environmental factors affecting their child’s sleep. By systematically investigating each possibility, the underlying cause can almost certainly be identified. We hope this information proves helpful.
