Nap lovers, be careful not to sink too long! Take a nap of 30 minutes or more increase the risk of developing atrial fibrillation according to one study Spanish presented at the congress of the European Society of Cardiology (ESC) held in Malaga (Spain) in April 2023. Atrial fibrillation is a heart rhythm disorder that results in a succession of rapid and disorderly contractions of the heart. During nearly 14 years old, the authors followed 20,348 volunteers aged on average 38 years (61% women), without atrial fibrillation at the start of the study. They got their medical background (diabetes, high blood pressure, etc.), their age and lifestyle (tobacco, physical activity, coffee, etc.). They separated them into 3 groups according to the daily length of their nap.

Risk of atrial fibrillation when the nap is too long

Result: people who slept 30 minutes or more a day was twice as likely to suffer from atrial fibrillation. “Daytime naps should be limited to less than 30 minutes” said study author Dr. Jesus Diaz-Gutierrez of Juan Ramon Jimenez University Hospital, Huelva, Spain. For him, “People with disturbed nighttime sleep should avoid relying on naps to fill the void”. Long naps can disrupt the body’s internal clock (circadian rhythm) and reduce the quality of sleep at night (alarm clocks, shortened sleep time).

What is the ideal length of a healthy nap?

In a second analysis, the Spanish researchers observed that people doing napping less than 15 minutes had a 42% reduced risk of developing atrial fibrillation. those who slept 15 to 30 minutes saw this same 56% reduced risk. So, the optimal duration of the nap suggested by these results would be between 15 and less than 30 minutes.

“Larger studies are needed to determine whether taking a short nap is better than not taking a nap at all. There are many potential explanations for the associations between napping and health. For example, a short daytime nap can improve circadian rhythm, lower blood pressure and reduce stress” recalled Dr. Jesus Diaz-Gutierrez.