How Our Sleep Patterns Change as We Age
Whether your infant's nap time dictates your whole schedule or you're battling your own middle-aged insomnia, sleep patterns can have a powerful impact on your health and daily life. As your sleep routine shifts due to aging, the quality and quantity of rest you need adjusts, too. "Sleep patterns typically change over time," says Dr. Charlene Gamaldo, M.D., of the Johns Hopkins Medicine Neurology Department. "It is important to be aware of normal changes in the patterns of sleep with age so you are better able to identify elements that are not normal and address them with your doctor." Ahead, exactly what you can expect from your sleep schedule over the years.
How Sleep Quantity Changes
The quantity of sleep we need decreases steadily with age, with the quickest drop occurring in young children: Newborns need 14 to 17 hours of sleep; infants, 12 to 15 hours; toddlers, 11 to 14 hours; and preschoolers, 10 to 13 hours. When children reach school age, they need nine to 11 hours of sleep each night, and young adults manage on eight to 10, says Dr. Gamaldo (despite your teenager's tendency to sleep until noon). Once you're over age 25, the sleep requirements bottom out at seven to nine hours per night.
How Sleep Quality Changes
Sleep occurs in four stages: During the first several minutes, your brain waves slow and your muscles relax as you fall asleep. In the second stage, light sleep, your heartbeat, breathing, and brain activity continue to slow down. The third stage provides longer periods of deep sleep, which allows you to feel rested in the morning, and the fourth stage—REM, which most people enter about an hour-and-a-half after falling asleep—is marked by increased brain activity and dreaming. "Children not only require more sleep, but spend a greater percentage of that time in dream and deep sleep," says Dr. Gamaldo. "The amount of dream sleep gradually declines until adulthood and then stabilizes after."
As we age, the time lost to deep sleep is filled with lighter rest—during which your brain is more likely to respond to external influences. "This is the reason why children, who have more deep sleep, can sleep through anything, including loud noises," explains Dr. Gamaldo. "With aging, slight noises are much more likely to wake you up because more of your sleep period is spent in those lighter stages. The key is the ability to fall back to sleep within 30 minutes and wake feel rested and restored. Due to these age-related changes, it is not uncommon to have greater desire to nap as we age to help make up for sleep that is more likely to get disrupted due to standard environmental triggers at night."
Other Factors That Influence Sleep
Lifestyle changes and environmental stress can also impact your sleep—just ask anyone adjusting to the noise of a city apartment after growing up in the suburbs; the parents of a fussy infant; or an employee adjusting to a wake-up that accommodates a new two-hour commute. Pre-bedtime behaviors can also increase or decrease your quality and quantity of sleep, shares Dr. Gamaldo: Healthy choices include limiting screens before bedtime, sticking to a consistent sleep and wake time, exercising during the day, and avoiding caffeine.