older people also tend to have more insomnia — “you lose some of the neurons that are involved in sleep onset as you age” — but they also tend to have more medical problems, such as restless leg syndrome or chronic pain disorders, and may be on more medications, which can affect sleep.
too much sleep just as bad as too little
dang-vu cautions against napping, as it can disrupt nighttime sleep. “for people who don’t have sleep problems, naps can be a powerful tool to restore your brain function and memory,” he says. “[but] make sure it’s not too long, 20 to 30 minutes maximum, and ideally not after 3 p.m.”
but then, too many z’s can be just as problematic as too few. “in epidemiology studies, those who sleep nine or more hours per night tend to [also] be at increased risk of heart disease, obesity, depression or other psychiatric conditions,” says ayas, adding what they don’t know is whether it’s because of the increased sleep time, or if other issues, such as certain diseases disrupt your snooze time, making you sleep more to make up for it.
chronic insomnia is defined as sleeping for six hours or less a night, at least three times a week, for more than three consecutive months. getty
apnea and narcolepsy
those with sleep apnea, a potentially serious condition, are usually loud snorers who stop breathing periodically during the night and often gasp for air. as a result, they’re not only drowsy during the day, they’re also at increased risk for car accidents, occupational injuries, heart disease, stroke, diabetes, and alzheimer’s disease.