Despite the vast amount of science to the contrary, good sleep is frequently ignored in the conversation about brain health optimization. If prioritizing sleep at night is seen as an afterthought, prioritizing a daytime nap can sometimes appear downright lazy or excessively indulgent. But what does the science tell us about naps and brain health? Should we skip the siesta or build it into our routines?
A brief overview of the nap
Let’s state the obvious: Napping is nothing new, nor is it unique to humans (as any dog and cat owner can instantly tell you). Albert Einstein, Winston Churchill and Thomas Edison were all nappers, and the famous philosopher Aristotle credited some of his insights to regular naps. Despite the lack of novelty of a nap, there’s still an active debate over whether it’s a good or bad thing that varies between countries, cultures and communities.
In Asian countries like China and Japan, napping is encouraged at work, and there’s even a term called “inemuri” in Japan for sleeping during work, an act seen as a positive reflection of working to the point of exhaustion. Perhaps unsurprisingly, in America, despite the introduction of the “power nap” by Dr. James B. Maas, napping at work tends to be poorly received, despite the fact that some large companies are instituting a more nap-friendly culture.
Outside of the office, the “siesta” custom is popular throughout the Mediterranean, often representing a nap between 2-5 PM. In Iceland, the term “úti” is used to describe a practice of taking an outdoor nap, which is believed to confer health benefits especially for young children. Beyond these general themes, what’s actually happening? In general, around 34% of Americans report taking a daily nap, a number that increases to over 50% of those over age 80. Interestingly, these numbers are very similar to what is found in the Mediterranean region, suggesting that certain “siesta” stereotypes may be less accurate.
The short-term benefits of napping on the brain
It’s well established that sleepy or sleep-deprived people think less clearly. This explains why napping can immediately improve certain metrics of brain function. In a 2021 meta-analysis of 381 people, an afternoon nap of around 1 hour was linked to better cognitive function, especially alertness. Another meta-analysis concluded that a daytime nap between 30-60 minutes significantly benefits cognitive performance in people who had a normal night of sleep or partial sleep deprivation the night prior. Additionally, a daytime nap has been shown to help reset the immune alterations that occur with sleep deprivation, a finding that may have major significance in light of recent work connecting immune imbalance with mental and cognitive health.
The long-term benefits of napping on the brain
For those trying to maximize learning, the benefits of a nap seem to transfer beyond the short-term. A 2019 study in Sleep found that, compared to cramming information, learning before and after a nap boosted memory for a week after the initial learning. A 2022 study in Frontiers in Public Health of over 4,000 people found that afternoon nappers of less than 30 minutes were found to have better overall cognition compared to those who did not nap or napped longer. Perhaps most compelling, a 2023 paper looked at over 378,000 people and concluded that daytime naps were linked to larger brain volume.
The potential risks for napping on brain health
Some data show that longer naps in particular may lead to issues that could damage brain health. In a 2016 meta-analysis, napping for longer than 60 minutes increased risk for developing type-2 diabetes by 50%. As it relates to the development of dementia, some research indicates that longer and more frequent naps predict higher risk for Alzheimer’s disease, but also that having dementia appears to increase napping. Importantly, this doesn’t mean that napping directly leads to risk for dementia, as it may well be that higher daytime sleepiness reflects underlying changes in the brain that could predispose to the disease. Higher frequency of naps are also associated with mental health issues, especially depression. Partially, this may be due to correlations between poor nighttime sleep and worse mental health. Another key consideration is that the nap-depression link may be more a reflection of depressive symptoms or underlying brain alterations leading to fatigue and napping, rather than the opposite.
How to nap best for brain health
- Don’t Replace Good Sleep with Naps: One of the biggest liabilities with the nap is a tendency to use them instead of taking a hard look at nighttime sleep quality. If you’re waking up tired, relying heavily on caffeine, or otherwise experiencing sleep-related issues, prioritize understanding these symptoms rather than just focusing on the nap.
- Keep Naps Short: Overall, research appears to suggest a benefit to keeping naps to 30 minutes or less. Longer naps can interfere with nighttime sleep by decreasing sleepiness at night.
- Timing Matters: Nap during the early afternoon, typically between 1 p.m. and 3 p.m., to align with the body’s natural circadian dip and to avoid interfering with nighttime sleep.
- Create a Restful Environment: Find a quiet, comfortable, and dimly lit space to nap, reducing potential disturbances and promoting relaxation.
- Listen to Your Body: Pay attention to your body’s signals. If you feel the need to nap regularly due to excessive daytime sleepiness, it may be indicative of underlying sleep disorders or health issues that require medical attention.
