Key TakeawaysAccording to a new study, inadequate sleep in middle age is associated with a higher risk of developing dementia.People in their 50s and 60s who got six or fewer hours of sleep a night experienced a 30% greater risk of developing dementia than people who got more sleep.Experts say that good sleep hygiene can help people get more restful sleep.

Key Takeaways

According to a new study, inadequate sleep in middle age is associated with a higher risk of developing dementia.People in their 50s and 60s who got six or fewer hours of sleep a night experienced a 30% greater risk of developing dementia than people who got more sleep.Experts say that good sleep hygiene can help people get more restful sleep.

A new study found that getting fewer than six hours of sleep per night in middle age is associated with an increased risk of developingdementia. Experts say that goodsleep hygienepractices can help people get better sleep—and more of it.

The National Sleep Foundation recommends that most healthy adults aged 18–64 get between seven and nine hours of sleep a night, and that older adults get between seven and eight hours.

What Is Dementia?

Dementia signsand symptoms can range from mild to severe and can include difficulty with memory, language skills,visual perception, problem-solving, self-management, and the ability to focus and pay attention.

Several factors raise a person’s risk of developing dementia:

How Senility and Dementia Differ

Sleeping Six Hours or Fewer

The study, which was published in the journalNature Communications, analyzed 25 years of data collected on 7,959 people who participated in the Whitehall II study—a longitudinal cohort study of more than 10,000 British men and women. Within the group, 521 cases of dementia were identified during the study’s time frame.

The participants in the story reported their own sleep duration, but about 3,900 of them wore sleep-tracking devices that verified the data they reported.

When they looked at the results, the researchers found that people in their 50s and 60s who reported sleeping six hours or fewer each night had a 30% greater risk of developing dementia compared to people who slept seven or more hours a night.

Sleep and Dementia

How Dementia Affects Sleep

Sabia says that it’s important “to consider [the] time between a putative risk factor and dementia diagnosis” because neurological processes that unfold 10 to 20 yearsbefore a person is diagnoseddrive the progressive disorder.

Why Might Less Sleep Increase Risk?

In the recent study, researchers did not determine why the people who got less sleep in middle age were more likely to develop dementia—they simply found a link. That said, they do note some possible mechanisms that might be involved.

Amit Sachdev, MDA healthy body is the best way to have a healthy brain.

Amit Sachdev, MD

A healthy body is the best way to have a healthy brain.

“Dementia is a multifactorial disease,” Sabia says. “This means that several factors are likely to influence its development.” Sabia notes that while it’s unlikely that lack of sleep alone would lead to someone developing dementia, “having a good night of sleep might be as important as other cardiovascular risk factors, such as healthy lifestyle and low blood pressure, fasting glucose, and cholesterol.”

Amit Sachdev, MD, medical director in the department of neurology at Michigan State University, tells Verywell that sleep is also “important for brain function" and that if a person consistently isn’t getting enough sleep, it can become difficult for their brain to work the way it should.

Why is sleep so important in midlife? Sachdev says that time of life, in general, “is when lifestyle begins to take its toll on the body." For example, Sachdev mentions that extra weight in youth could lead to sleep apnea in midlife, which in turn leads to interrupted sleep and poor brain function.

How to Get Better Sleep

Overall, Sabia says that the study “highlights the importance of having good sleep hygiene for brain health." To improve your sleep, Sabia recommends several sleep hygiene tips:

What Is Sleep Hygiene?

The link between lack of sleep in middle age and dementia needs further research, but Sachdev says that in general, good sleep is important for brain health. “A healthy body is the best way to have a healthy brain," Sachdev says. “Good brain health starts with the basics: eat right, exercise, and get good sleep.”

What This Means For YouGetting at least seven hours of sleep at night will help improve your overall health, and may lower your risk of dementia. It’s important to practice good sleep hygiene like going to sleep at the same time each night and avoiding devices before bed.

What This Means For You

Getting at least seven hours of sleep at night will help improve your overall health, and may lower your risk of dementia. It’s important to practice good sleep hygiene like going to sleep at the same time each night and avoiding devices before bed.

5 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Sabia S, Fayosse A, Dumurgier J, et al.Association of sleep duration in middle and old age with incidence of dementia.Nat Commun. 2021 Apr 20;12(1):2289. doi:10.1038/s41467-021-22354-2National Sleep Foundation.How much sleep do we really need?World Health Organization (WHO).Dementia.National Institute on Aging.What is dementia? Symptoms, types, and diagnosis.Centers for Disease Control and Prevention (CDC).What is dementia?

5 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Sabia S, Fayosse A, Dumurgier J, et al.Association of sleep duration in middle and old age with incidence of dementia.Nat Commun. 2021 Apr 20;12(1):2289. doi:10.1038/s41467-021-22354-2National Sleep Foundation.How much sleep do we really need?World Health Organization (WHO).Dementia.National Institute on Aging.What is dementia? Symptoms, types, and diagnosis.Centers for Disease Control and Prevention (CDC).What is dementia?

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Sabia S, Fayosse A, Dumurgier J, et al.Association of sleep duration in middle and old age with incidence of dementia.Nat Commun. 2021 Apr 20;12(1):2289. doi:10.1038/s41467-021-22354-2National Sleep Foundation.How much sleep do we really need?World Health Organization (WHO).Dementia.National Institute on Aging.What is dementia? Symptoms, types, and diagnosis.Centers for Disease Control and Prevention (CDC).What is dementia?

Sabia S, Fayosse A, Dumurgier J, et al.Association of sleep duration in middle and old age with incidence of dementia.Nat Commun. 2021 Apr 20;12(1):2289. doi:10.1038/s41467-021-22354-2

National Sleep Foundation.How much sleep do we really need?

World Health Organization (WHO).Dementia.

National Institute on Aging.What is dementia? Symptoms, types, and diagnosis.

Centers for Disease Control and Prevention (CDC).What is dementia?

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