Daytime Napping and Health Outcomes in Older Adults

Daytime napping is a widespread behaviour with both beneficial and adverse associations in older populations. Epidemiological studies have documented a U-shaped or J-shaped relation between nap duration and multiple health outcomes, including metabolic syndrome, type 2 diabetes, cardiovascular disease and cognitive function. Short naps (under 30–40 min) may enhance alertness, executive function and working memory without disrupting nocturnal sleep, whereas prolonged naps (over 60 min) have been linked to systemic inflammation, impaired glycaemic control and elevated cardiometabolic risk. Variation in genetic susceptibility, hormonal milieu and baseline sleep patterns appears to modulate these associations. Culturally ingrained napping traditions in Mediterranean and East Asian societies offer naturalistic settings to explore dose–response effects across diverse populations. Interventional studies suggest that strategically timed naps could support cognitive reserve, but the threshold at which benefits give way to risk remains under active investigation. Understanding the nuanced interplay between nap duration, circadian rhythm and underlying health is essential to inform guidelines on sleep hygiene and disease prevention in ageing societies.

Research from Nature Portfolio

A comprehensive dose–response meta-analysis has delineated a J-curve relation between nap duration and cardiometabolic outcomes, revealing that napping up to about 40 minutes daily carries no additional risk, but longer naps are progressively associated with higher odds of type 2 diabetes and metabolic syndrome. This synthesis of longitudinal cohort studies across Western and Asian populations underscored the importance of nap timing and duration as modifiable lifestyle factors and called for targeted trials to establish causality and physiological mechanisms.

Daytime Napping and Health Outcomes in Older Adults publication trend

The graph below shows the total number of articles in daytime napping and health outcomes in older adults across all publications each year (not limited to Nature Index journals).

Technical terms

Metabolic syndrome: A cluster of conditions including abdominal obesity, hypertension, dyslipidaemia and insulin resistance that increase the risk of cardiovascular disease and diabetes.

Homocysteine: An amino acid in the blood whose elevated levels are linked to cardiovascular and neurodegenerative disorders.

Glycaemic control: The regulation of blood glucose levels within a target range to prevent hyperglycaemia and hypoglycaemia.

Odds ratio: A statistical measure quantifying the strength of association between an exposure (e.g. long nap) and an outcome (e.g. diabetes).

References

1. Napping and Obesity in Adults – What do we Know?. Current Diabetes Reports (2024).
2. Sleep Duration, Midday Napping, and Serum Homocysteine Levels: A Gene–Environment Interaction Study. Nutrients (2023).
3. Association between napping and type 2 diabetes mellitus. Frontiers in Endocrinology (2024).
4. J-curve relation between daytime nap duration and type 2 diabetes or metabolic syndrome: A dose-response meta-analysis. Scientific Reports (2016).
5. Effects of a Short Daytime Nap on the Cognitive Performance: A Systematic Review and Meta-Analysis. International Journal of Environmental Research and Public Health (2021).