The Deep Sleep–Alzheimer’s Connection
Not getting enough deep sleep could raise your risk of developing Alzheimer's disease.

Protect Your Brain with Quality Rest
If you’ve ever needed a reason to take your sleep seriously, this might be it: a new study shows that not getting enough deep sleep could raise your risk of developing Alzheimer’s disease.
According to researchers at Yale School of Medicine, some people who spend less time in slow-wave sleep and REM sleep—the two deepest and most restorative stages—showed shrinkage in parts of the brain tied to early Alzheimer’s.
But why does deep sleep matter so much?
During these crucial sleep stages, your brain isn’t just resting—it’s busy:
- Sweeping away toxins and dead cells
- Repairing and restoring the body
- Processing emotions
- Consolidating memories
Dr. Richard Issacson, a leading Alzheimer’s prevention expert, explains that the connection between deep sleep and brain health is clear. Sleep plays a vital role in preserving both cognitive function and brain structure.
So how much deep sleep do you really need?
Experts say 20–25% of your night should be spent in deep and REM sleep. But here's the kicker: the amount of deep sleep you get naturally declines with age, and more than one-third of American adults already don’t get enough sleep to begin with.
How to Get More Deep Sleep
The good news? There are simple, science-backed ways to support sleep hygiene:
- Stick to a regular sleep schedule—even on weekends
- Create a cool, dark, quiet sleep environment
- Power down screens an hour before bed
- Skip alcohol before bedtime
- Try a relaxing routine like yoga, stretching, or a warm bath
- Avoid sleep meds when possible—they may affect sleep quality
While there’s no magic pill for better sleep, building good sleep hygiene habits can be a powerful step toward protecting your brain and your future. Deep sleep isn’t just about feeling rested—it’s about giving your brain the care it deserves.
Sweet dreams, healthier brain!
Dream big, work hard, sleep ambitiously,
Joe Castignani