And researchers have also been examining deep sleep and the role it plays in helping a person keep their memories.

“Deep sleep is the stage of sleep where our brain activity slows and we don’t wake as easily,” Dr. Deland explained. “This is dreamless sleep, usually occurring later during the night right before dreaming sleep, known as REM. During deep sleep, growth hormoneTrusted Source is released and the body performs recovery and clean up.”

A study from May 2023 says that deep sleep may help protectTrusted Source against memory loss in older people with elevated amounts of beta-amyloid in the brain. And a study released earlier this month found that applying deep-brain stimulation when a person is in deep sleep improvesTrusted Source their brain’s ability to make memories.

“We see less memory loss in older adults who have high-quality nightly sleep,” Dr. Sullivan said. “We also know that the restorative clearing-out functions of sleep are at their most effective during deep sleep, which removes some of the toxic proteins that build up to cause Alzheimer’s disease.”

“The commonly accepted belief is that deeper sleep helps you perform and consolidate memories, so if you don’t get to that part of sleep, then you don’t consolidate memories,” explained Dr. Clifford Segil, a neurologist at Providence Saint John’s Health Center in Santa Monica, CA.

“The interesting part of this theory is as you age by design, our brain doesn’t let you go into those deeper waves of sleep anyway. And by design, as people age, their sleep requirements go down. Younger people get more deep sleep than older people — that is why younger people are more easily able to consolidate and form memories,” he suggested.

And Dr. Merrill said that while deep sleep may decrease as we age, there are ways to help increase it.

“Taking a warm shower before you go to bed, [making] sure you don’t get any screen time after dark, not eating a big meal too close to bedtime — all these things may help [with] deep sleep,” he detailed.

Although it can sometimes be hard to make sleep a priority, all experts agree getting enough sleep is vital for not just good brain health, but good overall health.

“We know that poor general health puts a person at a higher risk for Alzheimer’s disease,” Dr. Wald said. “Without proper rest, our bodies cannot work properly in order to maintain health. Subsequently, it would seem to be a logical conclusion that poor sleep might lead to dementia.”

Here are some tips from experts on how to improve your sleep:

• try to wake up and go to sleep at the same time every day
• avoid electronics that emit blue lightTrusted Source — such as television, computers, tablets, or smartphones — at least 1 to 2 hours before bed.
• try reading instead of watching television before bed
• exercise daily, but not right before going to sleep
• avoid caffeinated beverages in the afternoon
• try not to nap in the afternoon
• avoid large meals at least 1 hour before going to sleep
• only go to bed when you feel sleepy
• establish a pre-sleep ritual to let your body know that it is time to wind down
• do a relaxing activity, such as meditation or deep breathing, before bedtime
• set up your sleeping area so it is cool, dark, and quiet
• use your bed for sleeping and intimacy only
• use a smartwatch or other device to track your sleep
• expose yourself to sunlight when you wake up.

And if you do find yourself not getting adequate sleep, Dr. Segil advised making sure to pay off your “sleep debt.”

“More sleep is better than less sleep and I’m a firm believer in sleep debt,” he continued. “If you’re unable to get a good night of sleep for any reason, please pay off your sleep debt as soon as possible, or sleep more the following night the amount of sleep you lost prior.”