Standard advice for treating insomnia includes a blanket rule: Avoid daytime napping. But the research tells a more nuanced story.
When naps are taken strategically, they don’t seem to interfere with nighttime sleep and can offer benefits, said Michael Grandner, PhD, director of the Sleep and Health Research Program at the University of Arizona, during his 2025 Embody webinar “How Better Sleep Promotes Mental, Metabolic, and Cardiovascular Health.” These benefits include reducing daytime fatigue and improving productivity, executive function, and learning.
Not all naps are equal. In general, Grandner explained, there are three kinds of naps.
Power Naps
These are the sleep equivalent of a snack you have during the day. Keep these brief (under 30 minutes) as any longer can put you into deep sleep, which can cause grogginess when you wake up. And as long as you try to take your power naps earlier in the day (before 3 p.m.), they can boost performance without impeding nighttime sleep.
Sleep Replacement Naps
This kind of nap is to nighttime sleep what a meal replacement shake is to a missed meal. “No one is going to mistake it for the real thing, but it'll help you get by in a pinch,” Grandner said. If, for example, you had a really poor night of sleep and you have the chance to nap for a few hours during the day before tackling a project at work or a family commitment, a longer nap can help you manage that. This is fairly common among shift workers. It's not an ideal set-up long-term, but it counts as sleep and can be used as a tool occasionally.
Accidental Naps
The naps you should avoid, Grandner said, are accidental ones, where you find yourself unintentionally falling asleep during the day. Accidental naps can be a sign that there's a problem with your nighttime sleep or another dimension of your health.
“You should be able to maintain wakefulness in the day when you want to,” Grandner said; if you can’t, it’s possible you have a sleep disorder, such as sleep apnea. Consider speaking with your doctor about doing a sleep study to get more information on your sleep patterns and quality.
