Are Naps Good for You? Benefits and Limits

What naps do well: alertness and performance

The clearest benefit of a nap is short-term. A 2021 meta-analysis that pooled 11 studies with 381 participants found that a daytime nap improved cognitive performance, especially alertness, for up to about two hours. The benefit was independent of age and sex. Most of the studies were done in labs, so the authors call for more research in real workplaces. [3]

A review by Dhand and Sohal notes that naps as short as 10 minutes can improve performance, and that naps under 30 minutes have several benefits, while longer naps are more often followed by grogginess. [2]

Naps as a tool against sleep debt

French sleep researchers led by Brice Faraut describe the nap as a possible “public health tool” against the consequences of sleep loss. Their review covers studies on accidents, work and school performance, stress, immune function and pain sensitivity. [1]

At the same time, they stress that the effect depends on nap length, frequency and age, and that more research is needed, especially for night and shift workers. A nap can relieve the effects of a short night, but it does not replace regular, sufficient night sleep.

What about the heart?

Two large observational studies point in a positive direction. In a Greek cohort of 23,681 adults followed for about six years, people who took a regular siesta had a 37% lower coronary mortality than those who did not, after adjusting for factors such as physical activity and diet. [4]

A Swiss study with 3,462 adults found that people who napped once or twice a week had about half the risk of cardiovascular events over five years compared with non-nappers. For people who napped almost daily, the higher risk seen at first disappeared once other health factors were taken into account. Nap length showed no link. [5]

These studies show associations, not cause and effect. People who can take a relaxed siesta may also differ in other ways, such as work stress or general health.

Bigger brains from napping?

One of the more surprising findings comes from a 2023 study using data from the UK Biobank. The researchers used genetic variants associated with napping, an approach called Mendelian randomization, to estimate whether habitual napping itself could affect the brain. They found a modest link between habitual napping and a larger total brain volume, about 15.8 cubic centimetres on average. [6]

However, the same study found no effect on the size of the hippocampus, reaction time or visual memory. It is an interesting clue, not a reason to expect a nap to change your brain. [6]

When naps can be a problem

The Mayo Clinic lists two main downsides: grogginess after waking (sleep inertia) and problems sleeping at night, especially after long or late naps. [7] If you already have trouble falling asleep, a nap can make the evening harder.

Frequent long naps can also be a symptom rather than a habit. The Mayo Clinic advises talking to a doctor if you find yourself needing naps more often than usual. [7] Dhand and Sohal note that sleep disorders and long shifts are common reasons for daytime napping. [2]

Who benefits most

• People with short nights due to work, children or travel.
• Shift workers, for whom a planned nap can reduce sleepiness. See napping on the night shift.
• People with a noticeable afternoon dip who have a quiet slot.

People who sleep well at night and feel alert in the afternoon do not need to nap. And people with insomnia should discuss naps with a professional, because naps can make night sleep worse.

How to nap in a healthy way

1. Keep it short, about 10–20 minutes, if you need to be alert afterwards. See how long a nap should be.
2. Nap early in the afternoon rather than late.
3. Leave time to wake up before demanding tasks.
4. Protect your night sleep first.
5. Watch for changes: needing much more sleep than usual is worth checking.

Common questions about naps and health

Is napping a sign of laziness?

No. Napping is common across cultures and ages, and a short nap can be a sensible way to manage energy.

Can naps make up for a bad night?

Partly, in the short term. They improve alertness for a few hours, but they do not replace regular night sleep. [1]

Is a daily nap bad for the heart?

In the Swiss study, the increased risk for daily nappers disappeared after adjusting for other health factors. [5] Frequent sleepiness still deserves attention.