Although short naps can be a helpful way to boost your energy during the day, experts say they do not provide the full health benefits of a good night's sleep and cannot fully compensate for insufficient sleep, Jyoti Madhusoodanan writes for the New York Times.

The benefits of napping

If you missed out on a full night of sleep, a short nap can be helpful in restoring some needed energy during the day.

"When you haven't gotten a great night of sleep, napping can really help improve things like reaction time and memory if you need to be working," said Molly Atwood, a clinical psychologist and behavioral sleep medicine researcher at Johns Hopkins Medicine.

According to Atwood, a 20- to 30-minute nap during the day can help you feel more alert without making you groggy or disrupting your sleep schedule later in the night.

Naps can also be important for people who work more irregular schedules, such as airline pilots, commercial drivers, physicians, or other shift workers. Short naps can help these workers stay sharp and alert during their shifts.

Similarly, naps can help older adults with age-related changes that disrupt their sleep, like having to use the bathroom frequently at night.

If you find yourself needing to nap, Atwood recommends keeping it short, no more than 30 minutes, so it doesn't interfere with your next night of sleep. She also noted that it's better to nap in the afternoon "when we have a natural dip in alertness and tend to feel sleepy."

Why good sleep at night remains important

According to Rebecca Spencer, a sleep science researcher at the University of Massachusetts Amherst, a midday nap can give you an energy boost to get through the day, but it likely isn't enough to counteract the health risks that come with too little sleep at night.

Based on CDC survey data from 2020, over a third of U.S. adults don't get the recommended seven hours or more of sleep at night. This lack of sleep can lead to several health risks, including obesity, high blood pressure, diabetes, coronary heart disease, stroke, and mental distress.

The quality of sleep you get is also important, Spencer said. When you sleep at night, you pass through several "sleep cycles," which last around 90 minutes.

Each cycle has four stages. During the first two stages, which are considered "light sleep," your muscles relax, your body temperature drops, and your heart rate and breathing slow down. The third stage is when you enter "deep sleep" and your body begins "the important work of repairing and building bone, muscle and other tissues, as well as strengthening the immune system and consolidating and processing memories," Madhusoodanan writes.

The final stage is rapid eye movement (REM). The REM stage is not as deep as the third stage, but is when you're most likely to dream and is believed to be associated with memory storage, learning, and mood regulation.

According to Atwood, it's normal to have a poor night of sleep every once in a while, but if you are consistently not going through all four sleep stages every night, your health may suffer.

Spencer also noted that naps during the day cannot compensate for a lack of sleep at night. Even if your total sleep time at night and during the day adds up to six or more hours, the health benefits will not stack up the same way.

Short naps that are less than 90 minutes typically only include the light stages of sleep without any of the deep, restorative sleep that you would get during the night. And while longer naps may include some beneficial deep sleep, you may end up waking up groggy and feeling less sharp overall.

If you are chronically tired or struggle to get through the day without a nap, it may be helpful to reach out to a behavioral sleep specialist.

"People tend to suffer for a while, and then they go to their primary care physician and get some medication," Atwood said. But seeing a sleep specialist will be more beneficial in the long-term rather than relying solely on medication. Sleep specialists can offer exercises or strategies like cognitive behavioral therapy to help you get more rest you need and ultimately feel better. (Madhusoodanan, New York Times, 3/28)