Overview

• The postprandial circadian dip between noon and 4 p.m. creates a prime window for brief naps to enhance alertness, mood and memory retention.
• Research endorses a 10- to 20-minute nap to avoid deep-sleep grogginess while a 26-minute rest has been shown by NASA and NTBS to increase performance by 34% and alertness by 54%.
• Fundación Española del Corazón reports that short naps can cut cardiovascular risk by about 37% by relieving stress and lowering blood pressure.
• Evidence links daily naps exceeding 60 minutes to a 40% higher Alzheimer’s risk in older adults and habitual daytime sleeping to a 12% increase in hypertension and 24% rise in stroke risk.
• Sleep experts warn that persistent long or frequent naps often signal underlying sleep or metabolic disorders associated with obesity, high blood pressure and type 2 diabetes.