Rest and Recharge: How Sleep Keeps Your Brain Healthy
Sleep isn’t a luxury—it’s one of the best things you can do for your brain. When you don’t sleep well, your brain misses its ‘clean-up’ time—when it clears waste, stores memories, and balances mood. Good sleep also helps your heart and blood pressure stay healthy.
Poor or irregular sleep—especially in midlife—can raise your risk of memory loss and dementia. The good news: sleep problems are common, but most are treatable. In this article, we will explore how better sleep supports your brain, mood, and overall health.
But it's important to remember, this is only one of many modifiable behavioral risk factors for Alzheimer's and dementia.
If you'd like a personalized plan, daily activities and support to help address all of your most pressing risks, sign up for a 2 week free trial of Mindr. Better brain health starts today.
Why Sleep Matters for the Brain
Sleep feels like a period when not much is happening, but there’s a ton of work going on behind the scenes while you rest. Sleep is your brain’s nightly reset button—supporting memory, focus, and repair. Here are just a few of the important processes that happen while you are in dreamland.
Cleaning out waste: During deep sleep, the brain clears away waste proteins like beta amyloid - the same substance that forms plaques in Alzheimer’s disease. Think of it like brushing your teeth: sleep helps clean up your brain before buildup causes problems. Skimping on sleep can interrupt this cleaning process. Those who sleep fewer than five hours a night have about twice the risk of developing dementia compared to people who sleep six to eight hours.
Protecting blood flow: Your brain needs a steady supply of oxygen and nutrients. Sleep apnea - a condition where your breathing stops and starts during sleep - interrupts that steady flow causing drops in oxygen and spikes in blood pressure that can damage tiny blood vessels in the brain and raise dementia risk. People with moderate to severe sleep apnea are about 70% more likely to have memory and thinking problems than those without it. The good news? Treating sleep apnea — for example, by using a CPAP machine — can improve oxygen flow, help you sleep better, and may slow memory decline.
Lowering inflammation and stress: When you don’t sleep well, your body releases more cortisol, a stress hormone that fuels inflammation. Chronic inflammation has been linked to diseases like diabetes, heart disease, and even Alzheimer’s. Sleep helps lower blood pressure and reduces inflammation, giving your body a much-needed break.
Strengthening memory and learning: During REM and deep sleep, your brain stores memories and organizes new information. This process protects brain plasticity, keeping your brain flexible and ready to adapt to change. Missing sleep makes it harder to focus, learn, and remember.
Common Sleep Problems to Know About
Sleep problems become more common with age with nearly half of adults over 55 having trouble sleeping. Insomnia - defined as having trouble falling or staying asleep - is very common and has been linked to memory problems. Treating insomnia early helps restore healthy sleep patterns and protect cognitive health. Simple changes like adjusting bedtime routines to include healthier sleep habits can create conditions which support healthy sleep. For more persistent cases, cognitive behavioral therapy for insomnia (CBT-I) can make a real difference.
Another sleep problem which becomes more common with age is obstructive sleep apnea which causes repeated pauses in breathing during sleep. Loud snoring, gasping, or waking up tired are common signs. If this sounds familiar, ask your doctor about a sleep test. Treatments such as CPAP therapy or weight management can make a big difference — for your sleep and your brain.
How Sleep Affects Dementia Risk
The 2024 Lancet Commission on dementia found that 14 modifiable risk factors - things you can change - account for almost half of all dementia cases worldwide. Sleep influences many of these including: obesity, high blood pressure, diabetes, depression, and social isolation. These influences are often circular - poor sleep can make these conditions worse, and they can degrade sleep quality in return.
Sleep helps regulate hormones that control metabolism, blood sugar and blood pressure. Poor sleep disrupts these systems, increasing brain blood vessel damage and your risk for diabetes, obesity, high blood pressure and dementia. Obesity on its own is a significant risk factor for dementia but excess weight is also a major risk factor for sleep apnea, which in turn harms brain and heart health. Losing weight and addressing these related conditions often improves both sleep and cognitive function.
People with chronic sleep problems are 10 times more likely to be diagnosed with depression and 17 times more likely to have anxiety than the general population. Poor sleep worsens mood and makes it harder to do the things you want to do like see friends and exercise. Conversely, loneliness and depression disrupt sleep - so these factors can amplify each other and dementia risk. Fixing sleep problems often makes you feel better emotionally and physically so you can get back to the healthy lifestyle you want to live.
Because sleep connects to nearly every system in the body, improving it has ripple effects everywhere.
Brain-Healthy Sleep Habits You Can Try
Making these small changes to your sleep habits can help you get more zzz’s - making you feel better today and protecting your brain in the future.
Practice good sleep hygiene: Good sleep hygiene creates the conditions necessary for a solid night of sleep. Avoid heavy meals, alcohol, and screens for two hours before bed. Create a cool, dark, and quiet space to rest, and stick to a regular bedtime routine. Allow time to wind down with relaxing activities like reading, journalling or stretching.
Be consistent: Going to bed and waking up around the same time every day, even on the weekends, helps your brain stay healthy. If you can get seven to nine hours of sleep a night, your brain will thank you. But even if you can’t always get seven full hours, keeping your sleep times consistent still lowers dementia risk.
Get help if you can’t sleep: If insomnia keeps you up, talk with your healthcare provider. CBT-I or short-term medication may help reset your sleep cycle.
Ask about sleep apnea. If you snore loudly, gasp during sleep, or still feel tired after a full night’s rest, get checked for sleep apnea. Sleep apnea raises your risk of high blood pressure and diabetes - both risk factors for dementia. Treating sleep apnea can help you get better sleep and protect your brain.
Move more and manage your weight: Regular activity and healthy weight support better sleep, lower dementia risk and reduce the risk of high blood pressure, diabetes and sleep apnea. Carrying excess weight and being inactive can cause sleep problems and sleep problems can impact energy levels and hormones which control hunger. It’s a vicious cycle with sleep problems and obesity compounding each other. It’s all connected - better sleep gives you more energy to keep up these healthy habits.
Let sleep fuel your brain-healthy life: Good sleep gives you the energy to eat well, stay active, socialize, and manage stress. When you wake up feeling refreshed, everything else becomes easier.
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The Bottom Line
Sleep is called the “foundation of brain health” for good reason. It affects your memory, your hormones, your heart, and your mood. Getting good sleep helps you think more clearly, feel better, and stay engaged with life.
Sleep problems are common, but they’re also treatable. If sleep has been a problem for you or someone you love, adjust your sleep hygiene or talk to your doctor. Treatment can improve energy, mood, and heart health - and may help keep your mind sharp for years to come. You have the power to change your sleep and protect your brain.
What’s Next
Improving sleep doesn’t have to be overwhelming and you don’t have to figure it out on your own. Mindr can help! With Mindr, you will have access to all of these success boosting tools:
An easy to follow personalized risk factor management plan that fits your life
Daily guidance and reminders so you know exactly what to do each day
Frequent assessments and tracking so you can see your progress
A human in the loop to support and encourage you
Many studies, including the U.S. POINTER trial, a study of lifestyle changes conducted by the Alzheimer’s Association, have shown that coaching support and structured intervention plans give people a statistically significant edge over those who are self-guided.
You wouldn’t still be reading this if having a healthy brain wasn’t important to you. The lifestyle changes that will get you there are within your reach. You have the will, we’ll show you the way - one day at a time. You can do this and we can help.
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