Do NOT nap for long.

by Jon Scaccia November 8, 2024

Napping—it’s one of life’s simple pleasures. For some, a quick snooze in the middle of the day can recharge the mind, while others swear by a cozy two-hour nap to shake off fatigue. But could there be a hidden cost to that luxurious midday rest? A recent study reveals that long naps may not be as harmless as we once thought, showing an unexpected link between extended napping and serious health risks, like increased mortality and cardiovascular disease.

If you’re thinking, “But naps make me feel good! How could they be harmful?” you’re not alone. Many of us have associated naps with comfort and relaxation. But just as with any habit, the devil is in the details, or in this case, the duration.

The Power of a Short Nap

Before diving into the science, let’s talk about the beauty of a quick, refreshing nap. Many studies have confirmed that short naps—around 20 to 30 minutes—can boost mood, enhance focus, and even reduce stress. Picture a busy workday where, after a brief catnap, you’re back on your feet, ready to tackle tasks with renewed energy. A short nap helps reset your brain without plunging you into deep sleep stages, which can leave you groggy and unfocused. It’s a bit like rebooting your phone when it starts acting up; a quick reset is sometimes all you need to get back to peak performance.

When Naps Become a Risk Factor

But what if you regularly indulge in longer naps? This recent meta-analysis, involving over 370,000 participants across 21 studies, took a closer look at the impact of napping on health outcomes, specifically examining how nap duration affects mortality and cardiovascular disease (CVD) risk. And the findings were surprising: long naps, those lasting an hour or more, were associated with a 1.22 times higher risk of all-cause mortality and a 1.37 times higher risk of cardiovascular issues compared to those who didn’t nap.

Why would napping, something that feels so natural and relaxing, be linked to such severe health outcomes? Researchers believe the answer lies in how long naps interact with our body’s natural rhythms and health markers.

The Sleep Rhythm Connection

Imagine your body is like an orchestra, with every part playing in sync to create a balanced rhythm. A good night’s sleep keeps this rhythm steady, while short naps work like short solos that add to the harmony without disrupting the flow. But extended naps, on the other hand, can throw off your body’s internal clock, particularly its circadian rhythm—the system that tells you when to wake up and when to sleep.

When you nap for an hour or longer, your body may enter deeper sleep stages, those typically reserved for nighttime. Waking up from these stages can disrupt your natural sleep-wake cycle, leaving your body confused and groggy. Over time, these extended naps can affect how your heart and metabolism function, potentially raising risks for conditions like heart disease and obesity.

A Closer Look at the Risks

The analysis showed a fascinating contrast: those who napped for less than an hour had no increased risk of mortality or CVD compared to non-nappers. But for those who napped an hour or more, the story was different. Here’s a closer breakdown:

• All-Cause Mortality: Those napping an hour or more had a 22% higher risk of mortality from any cause.
• Cardiovascular Disease: Long nappers had a 37% higher risk of CVD, including heart attacks and strokes.

These figures may sound alarming, but the researchers offer a possible explanation. Prolonged naps may lead to sudden shifts in heart rate and blood pressure, both of which are tightly linked to cardiovascular health. The rapid changes that come with waking up from a deep sleep stage may act as a stressor on the cardiovascular system, particularly if you have underlying health conditions.

Who’s at Risk?

While the data shows a strong link between long naps and health risks, it’s worth noting that these outcomes may not be the same for everyone. Age, overall health, and lifestyle play significant roles in how our bodies respond to naps. For instance, younger individuals who are generally healthy may not experience the same risks as older adults with pre-existing health conditions. It’s also possible that certain individuals may have a genetic predisposition to needing longer naps, which could alter how napping impacts their health.

Is Napping Safe for Everyone?

The researchers emphasized that these findings don’t mean we should all give up napping. Instead, it highlights the importance of being mindful about the duration of our naps, especially if we are prone to longer snoozes. If you feel a midday nap calling, try setting a timer for no more than 20–30 minutes to avoid slipping into the deeper stages of sleep. This approach allows you to reap the benefits of napping without overburdening your cardiovascular system.

What About Quality of Nighttime Sleep?

Interestingly, researchers found that those who reported longer nap durations often experienced poor-quality nighttime sleep. This pattern might suggest that long naps are sometimes a symptom of deeper sleep issues, like insomnia or sleep apnea. These conditions disrupt restful nighttime sleep, which in turn leads to greater daytime fatigue and the need for longer naps. In cases like these, addressing nighttime sleep quality might be a more effective way to feel energized during the day rather than relying on long naps.

The Bottom Line: Keep Naps Short and Sweet

Napping is a valuable tool in the wellness toolbox, but like any tool, it’s essential to use it wisely. Short naps of 20–30 minutes can help recharge you, boost your mood, and improve cognitive function. However, the longer naps that take you into deep sleep could carry unintended health risks if they become a regular part of your routine.

Whether you’re a devoted napper or just a casual snoozer, this research serves as a gentle reminder to listen to your body’s signals and approach naps with a bit of moderation. After all, your health is about balance—and napping, it seems, is no exception.

Join the Conversation

1. Do you take daytime naps? What benefits or downsides have you experienced?
2. How do you manage midday fatigue? Would you consider changing your nap habits based on this research?

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