Women's Health September 10, 2025 0 Comments

Is Your Sleepless Night Silently Steering You Toward Dementia? Here’s What Science Reveals and How You Can Fight Back Fast.

Ever found yourself staring at the ceiling at 3 a.m., wondering if those restless nights are slowly turning your brain into mush? You’re not alone—and new brainy research has some alarming news. A recent study suggests that insomnia isn’t just a pesky annoyance that kills your energy; it might be quietly nibbling away at your memory and brain health. Imagine this: people wrestling with insomnia are 40% more likely to face mild cognitive impairment or even dementia down the road. That’s no small potatoes. But here’s the kicker—this isn’t a doom-and-gloom story; it’s a wake-up call. More than 12% of Americans cope with chronic insomnia, so understanding these findings could be the key to keeping your brain sharp and your mind fierce for years to come. Ready to dive into what this means and how to fight back? LEARN MORE

A new study suggests that insomnia can negatively impact your brain health and memory.
People with insomnia were found to be 40 percent more likely to develop mild cognitive impairment or dementia than those without the condition.
Here’s what the latest research says, plus what you need to know to keep your brain healthy.

If you’re someone who struggles to fall or stay asleep, you know how frustrating it can be to deal with insomnia before a big event or meeting at work. But new research suggests that regularly having a hard time sleeping isn’t just bad for your energy levels the next day. It could actually negatively impact your brain health over time, too.

More than 12 percent of Americans have been diagnosed with chronic insomnia (a disorder marked by trouble falling asleep or staying asleep), which makes these findings especially important. While these results may sound like they’re creating even more stress for the insomniac community, doctors say that the good news is it may actually push people to seek treatment and better care.

Here’s what the study found, plus what sleep specialists want you to keep in mind going forward.

Meet the experts: Diego Z. Carvalho, MD, study author and assistant professor of neurology at the Mayo Clinic’s Center for Sleep Medicine; W. Christopher Winter, MD, a neurologist and sleep medicine physician with Charlottesville Neurology and Sleep Medicine and host of the Sleep Unplugged podcast; Kelsie M. Full, PhD, MPH, healthy aging researcher and assistant professor of medicine at Vanderbilt University Medical Center

What did the study find?

The study, which was published in the journal Neurology, tracked 2,750 cognitively healthy people with an average age of 70 for an average of 5.6 years. Of the people in the study, 16 percent had chronic insomnia, which is defined as having trouble sleeping at least three days a week for three months or more.

At the beginning of the study, participants were asked whether they had been sleeping more or less than usual over the prior two weeks. They also completed annual thinking and memory tests, and some participants had brain scans done to look for signs of damaged brain tissue or amyloid plaques, which are proteins that are linked to Alzheimer’s disease.

Over the course of the study, 14 percent of the people with chronic insomnia developed mild cognitive impairment or dementia, compared to 10 percent of the participants who didn’t have insomnia.

When the researchers accounted for factors like age, high blood pressure, use of sleep medications, and a sleep apnea diagnosis, they discovered that people with insomnia were 40 percent more likely to develop mild cognitive impairment or dementia than those without the condition. The researchers noted that this was the equivalent of about 3.5 extra years of brain aging.

Participants with insomnia also had faster declines on thinking test performances compared to participants without insomnia.

Why is insomnia linked to brain aging?

There are a few different things that could be at play here. At baseline, sleep is important for overall brain health, and plays a role in clearing out waste products that build up in your brain during the day, says Diego Z. Carvalho, MD, study author and assistant professor of neurology at the Mayo Clinic’s Center for Sleep Medicine. Sleep is also important for heart rate and blood pressure regulation, improved insulin sensitivity, how well your body tolerates blood sugar, and more, he says.

In the short term, having chronically disrupted sleep can mess with memory and focus, says Kelsie M. Full, PhD, MPH, healthy aging researcher and assistant professor of medicine at Vanderbilt University Medical Center. But over time, that poor sleep can lead to “cumulative deficits” in your cognitive performance and cause dysfunction in daily processes that help to keep your brain healthy as you age, she says.

“Poor or reduced sleep may lead to an ‘brain overload,’” Dr. Carvalho says. Over time, that can cause the build-up of “toxic” elements like inflammatory markers, proteins linked to Alzheimer’s disease, and changes in small blood vessels in the brain, he explains.

It’s important to stress that the study didn’t find that insomnia causes dementia—it simply found a link. Insomnia is also a complicated condition with a lot of different factors, making this link more difficult to parse, says W. Christopher Winter, MD, a neurologist and sleep medicine physician with Charlottesville Neurology and Sleep Medicine and host of the Sleep Unplugged podcast.

“Insomnia also tends to travel with other chronic illnesses, psychiatric disorders, shift work, and circadian disorders—so we run into trouble when we treat it like a discrete entity, like shingles,” Dr. Winter says. “There are many things under the large tent of items that one might describe as ‘insomnia’ that are known to create long-term health consequences. I suspect many of those things are at play.”

Dr. Winter also points out that this can be especially complicated because dementia can lead to poorer sleep.

What to do if you have insomnia

If you suspect that you have insomnia, Dr. Winter says it’s important to consult with a sleep specialist and get an evaluation. Dr. Carvalho agrees, noting that many older patients simply think that having trouble sleeping is just a normal part of aging. It doesn’t have to be!

And with all this being said, Dr. Winter says there’s no need to panic about your long-term health if you’re struggling with sleep. “We as sleep scientists do a terrible job at differentiating sleep deprivation from insomnia and also properly explaining what insomnia is,” he says. “I see patients on a regular basis that go to bed at 8 p.m. and set their alarms for 8 a.m., with a one-hour nap after lunch. They always struggle to ‘get to sleep’ or ‘stay asleep’—this is not a sleep problem, it’s an expectation problem.”

Dr. Winter points out that older adults don’t need 12 hours of sleep and a nap. “The ‘insomnia’ becomes a problem of efficiency, like buying too much dinner and not being able to finish it,” he says.

But if you feel like your sleep expectations are on point and you’re still struggling to get enough sleep, Full says it’s time to talk to healthcare professional. “You can work with a professional to identify a healthy sleep routine and sleep hygiene habits and potentially effective treatment option,” she says.

Korin Miller is a freelance writer specializing in general wellness, sexual health and relationships, and lifestyle trends, with work appearing in Men’s Health, Women’s Health, Self, Glamour, and more. She has a master’s degree from American University, lives by the beach, and hopes to own a teacup pig and taco truck one day.