Older adults who nap every day or most days are nearly 50% more likely to develop dementia, according to a large longitudinal study. The research, published in The Journal of Gerontology: Medical Sciences, tracked 966 adults aged 65 and older who had no memory or thinking problems in 2013.
Key Risk Factors
Ten years later, investigators linked frequent, unintentional daytime napping to a 39% rise in dementia risk and a 48% rise for those who nap most days. Naps lasting 30 minutes or less correlated with a 40% higher dementia risk after adjusting for health variables, while longer naps showed a weaker association.
These associations persisted even after accounting for nighttime sleep duration, daytime drowsiness and sleep‑apnea indicators. The link remained strong after excluding participants who developed dementia in the first five years, suggesting that altered nap habits can precede diagnosis by years.
Expert Insight
Study authors Adam Spira, Ph.D., and postdoctoral fellow Kening Jiang, Ph.D., emphasized that nap frequency and intentionality provide deeper insight than nighttime sleep alone. “Our findings highlight the importance of looking beyond nap length and considering how often and whether naps are planned,” they told Fox News Digital.
Caveats
The analysis is observational, so it cannot prove that napping causes dementia, the authors warned. “We did not intervene to change napping habits, so we cannot determine causality,” Spira and Jiang added.
Implications
Clinicians may monitor daytime napping patterns as an early warning sign of cognitive decline, especially when naps become frequent or occur unintentionally. The link remained strong after excluding participants who developed dementia in the first five years, suggesting that altered nap habits can precede diagnosis by years.
Researchers stress that while the study does not establish causation, tracking nap behavior could aid early detection of dementia risk.
