Is Junk Sleep really a Thing?

In his book "Healthy Sleep Habits, Happy Child," baby sleep expert Marc Weissbluth, M.D., warns about the concept of "junk sleep." This term refers to poor sleep quality that babies may experience if they do not follow a consistent sleep routine and sleep in their own beds. Weissbluth emphasizes the importance of establishing a regular sleep schedule to avoid the long-term effects of unhealthy sleep habits. He suggests that children who don't learn to sleep well may struggle with sleep as adults. Weissbluth presents a structured approach based on a child's natural sleep patterns to cultivate beneficial sleep habits. The book, first published in 1987 (republished in 2005), makes some alarming statements:

“Junk food is not healthy for our bodies and neither is a ‘junk sleep’ schedule. You try not to let your child become overly hungry, so don’t let your child become overly tired.”

“WARNING: If your child does not learn how to sleep well, he may become an incurable adult insomniac, chronically disabled from sleepiness and dependent on sleeping pills,”

In Healthy Sleep Habits, Happy Child, Weissbluth preaches with authority and reassurance about his, “step-by-step regime for instituting beneficial habits within the framework of your child’s natural sleep cycles.”

Many self-proclaimed baby sleep experts discourage babies from sleeping anywhere other than their own cots in a darkened room, deeming sleep environments like moving vehicles or being held in a parent's arms as inadequate for restful sleep, leading to what they term as "poor sleep." Some parents strictly follow advice from baby sleep training books to ensure consistent and proper sleep at home and at designated times, believing that babies need to be taught how to sleep to align with a desired sleep standard. While teaching babies to sleep independently is common in the US, UK, and Australia, it may not be widely accepted in other cultures where babies sleeping close to their mothers is the norm. Interestingly, modern parents sometimes encourage babies to conform to non-natural sleep behaviors to accommodate adult schedules, potentially contributing to sleep issues among adults today.

The term "junk sleep" is used to describe how screen usage before bed affects adults' sleep. However, the importance of babies' sleep location is questioned. Is sleep quality more important than quantity for babies and toddlers, and does where they sleep impact this quality?

Anthropologists note that historically, babies have slept at the breast, being held, carried, or in bed with their mothers. This sleeping approach is normal in many human and primate societies. Research shows that 67% of cultures worldwide share a sleep space with children, with 46% sharing a sleep surface. Indigenous communities across continents commonly practice close physical contact during the day and co-sleeping at night.

In many parts of Asia and the South Pacific, including Japan and Indonesia, co-sleeping is a traditional practice where parents share their bedrooms and beds with their children for several years. Balinese babies in Indonesia sleep with their mothers until they are three years old and are often carried on their mother's back during daily activities. Italian babies typically do not have a specific bedtime and often fall asleep while being put down by their parents in a shared bedroom. In Turkey, breastfeeding to sleep is common, and babies are usually swaddled and rocked to sleep in cradles. Across various cultures, babies are soothed to sleep through rhythmic movements in baby slings, hammocks, and cradles, while lullabies serve as a universal soothing method. Nomadic tribes space their babies to allow for carrying them until around the age of four when their legs are strong enough to keep up with the tribe. Settling babies and young children to sleep using breast-feeding, movement, and close physical contact has been a normal, natural, and essential practice throughout human history.

The discussion around the impact of alternative sleep methods on sleep quality is engaging. Sleep trainers discourage the use of sleep props such as car seats, prams, and baby carriers, claiming these can impede quality sleep and foster dependence. On the other hand, some parenting resources advocate for these items as beneficial sleep aids. Research indicates that rhythmic movements can help infants and toddlers soothe and drift off to sleep, resembling the comforting environment of the womb. This natural inclination towards calming through movement is also seen in children's play activities, underscoring the strong association between rocking and sleep in babies.

While baby trainers advise against breastfeeding babies to sleep, citing the importance of allowing infants to self-settle, this practice is rooted in both natural behavior and scientific evidence. For instance, the Kung people of Africa breastfeed their babies frequently and maintain close physical contact, resulting in seamless and peaceful sleep transitions with minimal fuss. Breastfeeding triggers the release of the hormone CCK, which promotes relaxation and sleepiness in both the mother and the baby. Additionally, breastmilk contains components that facilitate the induction of sleep. Overall, breastfeeding babies to sleep can be a dependable approach to help them comfortably and naturally drift off to sleep.

Infant sleep differs from adult sleep due to the simple sleep cycle in babies. Babies have two sleep stages - active and quiet - which make up a complete sleep cycle lasting 40-60 minutes. In comparison, adults undergo multiple sleep stages, including deep sleep and REM sleep.

Babies start by entering the active stage for around 20 minutes when they fall asleep, a light sleep phase where they are easily disturbed. Midway through the cycle, they shift into quiet sleep, a deeper stage where they are less prone to waking up from stimuli.

It's common for babies to wake up slightly or fully at the end of the active stage and need help to go back to sleep or to eat. This waking is mainly due to the baby's immaturity rather than the sleeping environment. As their sleep stages mature and they spend less time in REM sleep, babies will improve in returning to sleep after waking.

Adult sleep cycles of 60-100 minutes don't form until school age. In the early years, children have more light REM sleep compared to adults. Newborns spend half of their total sleep in light REM sleep, three-year-olds spend 30%, while adults spend about 20%. This increased time in lighter sleep is thought to protect against SIDS. Children's sleep patterns support their rapidly growing brains. They might wake up needing food, interaction, or comfort, not just due to sleep conditions.

Ultimately, the main focus is on the well-being of both the mother and the baby. If the baby is getting enough sleep, then the method being used is probably suitable. Whether the baby sleeps in a nursery or in-arms, all sleep is beneficial. There is no such thing as "junk sleep," and no evidence supports the notion that babies need to sleep in isolation and darkness for good rest. Historically, mothers have typically kept their babies nearby and encouraged their sleep, whether cuddled in their arms or at the breast.