Are Afternoon Naps Bad for Your Brain? Churchill, Dementia and the Science of the Siesta

The humble afternoon nap, one of life's simplest pleasures, has become the latest subject of scientific controversy. A new study suggests that frequent daytime napping among older people may be associated with an increased risk of dementia. For those who enjoy a brief afternoon sleep, this sounds like another example of medical researchers discovering something dangerous about an ordinary human activity that generations have enjoyed without giving it much thought.

An entertaining article in Blaze Media, entitled "The Scientists Are Coming for Your Afternoon Nap," examines the research and asks whether we should really be worried. Its answer is reassuring, although not dismissive of the science. The evidence suggests that the distinction between deliberately taking a refreshing nap and experiencing uncontrollable daytime sleepiness may be more important than the simple fact of sleeping during daylight hours.

The article begins with Winston Churchill, whose daily afternoon nap was almost as famous as his cigars and whisky. Churchill did not merely doze in an armchair. He undressed, climbed into bed and used specially fitted beeswax earplugs to exclude disturbances. His afternoon sleep was a carefully protected part of his routine, even during the Second World War, when the demands of political and military leadership frequently kept him working late into the night.

Churchill believed that an afternoon sleep effectively divided the working day into two productive periods. Instead of becoming exhausted by evening, he could resume work with renewed energy and continue well into the night. Given the extraordinary pressures under which he operated, it is hardly surprising that he valued this arrangement.

But Churchill is also an interesting example for another reason, one that discussions of his napping habits sometimes overlook: his considerable consumption of alcohol.

Churchill's drinking has been extensively discussed by biographers and historians, including David Irving. His fondness for champagne, whisky and other alcoholic beverages is beyond dispute, although the precise extent of his consumption, the strength of his drinks and the degree to which alcohol impaired his functioning remain subjects of disagreement.

There is also an interesting personal recollection relevant to this history. A family account from the writer's father-in-law, who worked as a doorman at a bar Churchill frequented, describes an occasion when Churchill collapsed after drinking and had to be caught before he fell. This is an eyewitness account passed down within the family, rather than an independently documented historical incident, but it illustrates the reputation Churchill acquired for substantial drinking.

It raises an obvious question. Was Churchill's afternoon nap simply an ingenious method of increasing productivity, or was it partly a response to the physiological consequences of his drinking and irregular sleeping hours?

Alcohol can initially produce sedation, but it also disrupts normal sleep architecture, particularly during the latter part of the night. Heavy drinking may therefore leave a person tired during the following day, even after apparently adequate time in bed. Churchill's demanding schedule provides another possible explanation for his afternoon fatigue.

None of this establishes that alcohol caused his daily naps. Churchill himself presented the practice as a deliberate strategy for managing his working day. Nevertheless, he was hardly an ideal experimental subject from whom to draw conclusions about the health benefits of daytime sleeping.

The modern scientific evidence is more revealing.

The new Johns Hopkins research discussed by Blaze Media followed 995 Americans aged 65 and older for up to a decade. Researchers examined their daytime napping habits and subsequent development of dementia.

The headline finding was that participants who napped most days or every day had a 48 per cent higher relative hazard of developing dementia than those who rarely or never napped.

At first glance, this appears alarming. But the distinction between association and causation is crucial. The study did not demonstrate that napping damages the brain or causes dementia. It established a statistical relationship between certain patterns of daytime sleeping and later dementia diagnoses.

That relationship could have several explanations.

One possibility is that excessive daytime sleepiness reflects early neurological changes occurring before dementia becomes clinically apparent. The disease process might therefore contribute to increased napping, rather than increased napping contributing to the disease.

Another possibility is that people who nap frequently are more likely to have underlying medical conditions, disturbed nighttime sleep or other factors associated with cognitive decline.

This is where the most interesting finding emerges. According to the study, people who fell asleep unintentionally had a 39 per cent higher relative hazard of dementia. Those who deliberately chose to nap, however, did not show a statistically significant association after adjustment for other relevant factors.

This distinction should make us cautious about sensational headlines. A person who deliberately lies down for twenty minutes after lunch is not necessarily comparable to someone who repeatedly falls asleep while reading, watching television or participating in ordinary activities.

The latter pattern may indicate a medical problem that deserves investigation.

Other research reinforces the need for caution. A 2024 meta-analysis in Sleep Medicine Reviews, examining 44 cohort studies involving approximately 1.86 million participants, found associations between habitual daytime napping and several adverse health outcomes. Longer naps, particularly those lasting 30 minutes or more, were associated with increased risks in some analyses.

However, the same review found associations with reduced cognitive impairment and sarcopenia, illustrating the complexity and sometimes contradictory nature of the evidence.

A broader umbrella review published in 2026 examined 16 meta-analyses covering numerous health outcomes. It found that relatively short naps could improve cognitive performance and reduce fatigue, while longer naps were more frequently associated with adverse outcomes. Importantly, the authors acknowledged that much of the underlying evidence was of low quality and observational in nature.

A further review of Mediterranean napping traditions, published in 2026, found no consistent relationship between daytime napping and lifespan. Some studies suggested benefits, others found no association, and some reported increased risks, particularly among older men taking longer naps.

The overall picture is therefore much less alarming than a simple claim that afternoon sleeping causes dementia.

Indeed, there is substantial experimental evidence that short naps can improve alertness and performance. NASA research involving long-haul airline pilots found that participants who obtained an average of approximately 26 minutes of sleep subsequently performed better and demonstrated greater alertness than those who remained awake.

The American military has also recognised the value of strategically timed sleep. The Walter Reed Army Institute of Research recommends tactical napping as a means of maintaining performance during periods of prolonged activity and anticipated sleep deprivation.

Such practices are hardly surprising. Human cognitive performance deteriorates with fatigue, and sleep is one of the body's fundamental restorative processes.

There is also a natural decline in alertness during the early afternoon, influenced by circadian rhythms and the accumulation of sleep pressure. This helps explain why the afternoon siesta has become an established cultural practice in many societies.

The fact that an activity is traditional does not automatically establish that it is healthy, but neither should an ordinary physiological response be treated as pathological merely because it has become the subject of an epidemiological association.

For people who sleep adequately at night, a brief afternoon nap may provide a useful improvement in alertness, concentration and mood. For those experiencing chronic sleep deprivation, however, occasional napping cannot fully compensate for persistently inadequate nighttime sleep.

There are also practical limits. Long naps can produce sleep inertia, the unpleasant grogginess that sometimes follows awakening from deeper sleep. Late-afternoon naps may interfere with the ability to fall asleep at night, especially in people already experiencing insomnia.

For many adults, a planned nap of approximately twenty to thirty minutes in the early afternoon is a reasonable approach, although individual responses differ.

The more important warning concerns a change in sleeping behaviour. An older person who suddenly begins falling asleep repeatedly during the day, despite apparently adequate nighttime rest, should not automatically dismiss this as an ordinary consequence of ageing. Sleep apnoea, medication effects, cardiovascular conditions, neurological changes and other medical problems may be involved.

This is quite different from choosing to take a short restorative rest.

The broader issue is how scientific findings are communicated to the public. Observational research frequently identifies associations between ordinary activities and later disease. Coffee drinking, sleeping duration, dietary habits, exercise patterns and numerous other behaviours have all been linked to health outcomes in studies that cannot necessarily establish causation.

Such research is valuable, but its findings are easily exaggerated when translated into headlines. A reported increase in relative risk does not tell an individual what their absolute risk is, and a statistical association does not prove that changing the associated behaviour will prevent disease.

The temptation is to transform every new study into another rule governing everyday life. Yet human biology is complicated, and the same behaviour may have different implications depending on age, health, sleep quality and personal circumstances.

Churchill's example is useful precisely because it reminds us that sleeping habits exist within a broader pattern of living. His afternoon nap cannot be separated entirely from his unusual working hours, formidable responsibilities, drinking habits and individual constitution.

He was extraordinarily productive, but that does not mean every aspect of his lifestyle deserves imitation. Nor does his productivity demonstrate that napping itself was responsible for his achievements.

The sensible conclusion is neither that everyone should imitate Churchill nor that older people should abandon their afternoon rests for fear of dementia. The available evidence suggests that short, deliberate naps can be beneficial for alertness and cognitive performance, while persistent or involuntary daytime sleepiness may be an important warning sign of underlying health problems.

There is no convincing evidence that an occasional planned afternoon nap causes dementia. Nor is there sufficient evidence to recommend napping as a method of preventing dementia or extending human life.

For those who enjoy a brief afternoon rest and wake feeling refreshed, the latest findings provide little reason for panic. Churchill may not have been an ideal model of healthy living, but his appreciation of the restorative possibilities of sleep was not entirely misplaced.

https://www.theblaze.com/lifestyle/the-scientists-are-coming-for-your-afternoon-nap