The Surprising Link Between Sleep and Alzheimer’s Disease
May 22, 2025
Getting a good night’s rest can restore your body and mind. And it may help combat symptoms of Alzheimer’s disease, too. Almost 7 million Americans 65 and older are living with the disease, which causes the death of brain cells and memory loss.
Because there is no cure, people living with Alzheimer’s and their caregivers rely on slowing the progress of the disease. Our experts explain the link between sleep and its effect on slowing disease progression.
What Is Alzheimer’s Disease?
Alzheimer’s disease is a progressive neurodegenerative disorder that damages the connections between brain cells. This can lead to:
- Memory loss
- Difficulty thinking and planning
- Trouble with speech and daily function
Alzheimer’s is the most common disease that causes dementia. Dementia is a general term used to describe a collection of cognitive, functional and behavioral symptoms caused by other diseases. Not all cognitive decline is caused by dementia, and dementia is not a normal part of aging.
Who’s at Risk for Alzheimer’s?
Age is the biggest risk factor for Alzheimer’s, says Georges A. Ghacibeh, M.D., neurologist and sleep specialist at Hackensack Meridian Neuroscience Institute at Hackensack University Medical Center. “Most people develop signs after age 60, but people with certain genes may see it in their 50s.”
Poor Sleep: an Alzheimer’s Warning Sign
Poor sleep is often one of the earliest signs of dementia, says Manisha Parulekar, M.D., chief of Geriatrics and co-director of the Center for Memory Loss and Brain Health at Hackensack.
If you get a good night’s sleep, your memory and decision-making improve. “But poor sleep limits those abilities and may contribute to dementia,” she says.
It’s not always clear which condition comes first — poor sleep or dementia, says Dr. Ghacibeh. Research suggests that not getting enough rapid eye movement, aka REM, sleep may be linked to Alzheimer’s, as an early warning sign or as a risk factor.
“Can you improve cognitive function by improving the quality of sleep? That’s probably true,” Dr. Ghacibeh adds. “Your brain is most active when you rest. It organizes memories and forms connections during deep sleep.”
Four to five times during a whole night’s sleep, REM clears the mental clutter left after this organizing process.
“If there’s not enough time in the REM cycle, the brain can’t remove excess connections, which increases the risk of Alzheimer’s,” Dr. Ghacibeh says.
9 Ways to Boost REM Sleep
The good news is there are multiple ways to promote good sleep.
- Aim for seven to nine hours of sleep each night.
- Stick to a schedule. Go to bed and wakeup at the same time each day.
- Nip napsat 20 minutes, Dr. Ghacibeh says. “The more you nap during the day, the less likely you’ll have deep sleep at night.”
- Cut caffeine and alcohol use in the afternoon and evening.
- Drop excess weight. “Losing even three to five pounds can improve sleep,” Dr. Parulekar says.
- Exercise. “The more active you are during the day, the more likely you’ll sleep well at night,” Dr. Ghacibeh says. Exercised muscles release chemicals that can aid deep sleep.
- Dim your lights and avoid smartphone and TV screens one to two hours before bed.
- Create a relaxing nighttime ritual. Try a warm shower, a book, stretching, gentle yoga, meditation or soothing music.
- Ask your doctor before taking sleep aids. “Long-term use of some sleep aids may increase your risk of dementia,” Dr. Parulekar says.
Still Need Help with Sleep or Memory?
Tell your doctor if you snore loudly, are groggy during the day, or are still sleeping poorly despite taking the steps above. You may have sleep apnea or another sleep disorder.
Your doctor can review your symptoms and family history, and order tests to learn more, Dr. Parulekar says.
“Your doctor can prescribe drugs to boost memory and cognitive function,” Dr. Ghacibeh says. “Some Alzheimer’s medicines also promote REM sleep.”
“The sooner we address dementia, the better the outcome for you,” says Dr. Parulekar. “Many interventions slow its progression.”
Next Steps & Resources
- Meet our sources: Manisha Parulekar, M.D, and Georges A. Ghacibeh, M.D.
- Make an appointment with a sleep specialist, or call 800-822-8905.
- Learn more about memory loss and brain health at Hackensack Meridian Health.
The material provided through HealthU is intended to be used as general information only and should not replace the advice of your physician. Always consult your physician for individual care.
