If you have not already done so, please read Blog Posts 1 through 5 that describe how sleep is important and beneficial. I will post specific information for parents and children based on my book, “Healthy Sleep Habits, Happy Child.” Please do not be put off by my book’s length. This is a reference book. Read only the topic of interest to you.
To better understand the importance of sleep timing (when your child falls asleep), appreciate the fact that there is a genetically controlled and automatic circadian sleep rhythm (Blog Post 112). This 24-hour rhythm of brain output is for sleep and wakefulness; it develops in infancy, and changes as the child develops. Parents cannot change this rhythm. Parents can guarantee high-quality sleep when they soothe their child to sleep as the brain shifts into the sleep mode. Chronic late bedtimes cause sleep deprivation, and this causes increased pressure to sleep so that the overtired child can actually sleep when the brain is in a more wakeful mode. But the result is poor-quality sleep.
• Late or irregular bedtimes cause lower academic test scores and are more harmful than short sleep durations.
A 2022 study of teen-agers between 15-16 years showed that staying up late at night and having more variable night-to-night bedtimes was associated with lower academic test scores. This study is notable because it used objective recordings of sleep measurements (actigraphy) and nationally standardized academic test scores. “The relationship between academic performance and sleep timing and consistency were more pronounced than that for sleep duration.” This means that it might be more important when your child falls asleep than how long your child sleeps.
• Children are larks, not owls. Children’s brains crave an early bedtime; they are ‘larks’, not ‘owls’ (Blog Post 70).
• Late bedtimes with normal sleep durations (due to later wake-up times, longer naps, or both) causes obesity in children (Blog Post 81), a shorter child (Blog Post 23), and behavioral problems (Blog post 69).
• Late bedtimes have become more common (Blog Post 69). This creates the false impression that it is ‘normal’ for children to fall asleep later. For example:
Bedtime (PM) by age:
Age | 1974 | 1979 | 1986 | 2011-2015 |
6 months | 7:18 | 7:41 | 8:16 | 8:54 |
1 year | 7:08 | 7:35 | 7:46 | 8:39 |
2 years | 7:08 | — | 8:07 | 8:54 |
• Late bedtimes cause sleep problems (Blog Post 7).
• Irregular bedtimes are harmful (Blog Post 12).
More reading:
Why early bedtimes are important for children (Blog Posts 91 and 109) and their mothers (Blog Post 109).
Problems associated with late bedtimes are not widely appreciated (Blog Post 38 and 109).
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