This Sleep Stage Is Key To Managing Anxiety — But It Declines With Age
If you've noticed anxious feelings sticking around longer than usual as you age, you're not the only one. Many people find anxiety becomes harder to regulate as they get older, and for years, scientists assumed this was simply a byproduct of aging brains and accumulating stress.
But new research1 points to a different culprit: what's happening (or not happening) during your deepest phase of sleep.
Studying brain activity while asleep
Researchers at UC Berkeley wanted to understand why anxiety symptoms tend to increase with age, and whether sleep plays a role. They recruited 61 cognitively healthy older adults (ages 65 and up) with varying levels of anxiety. Each participant spent a night in a sleep lab with EEG monitoring, completed anxiety assessments before and after sleep, and underwent brain imaging the following morning.
A subset of 24 participants was also tracked over approximately four years to see how changes in sleep related to changes in anxiety over time.
The researchers focused specifically on slow-wave activity (SWA), the brain waves that define the deepest stage of non-REM sleep. This is the phase when your body does its most restorative work, and when scientists believe your brain does most of it's emotional recalibration overnight.
Impaired deep sleep predicted higher next-day anxiety
Participants with reduced slow-wave activity during the night reported higher anxiety the next day. This effect was specific to slow waves. Other sleep features, like REM sleep, didn't show the same relationship.
The association held up even after researchers controlled for age, gender, trait anxiety levels, total sleep time, and sleep efficiency. In other words, it wasn't just that anxious people slept poorly. It was that impaired deep sleep itself appeared to disrupt the brain's ability to regulate anxiety overnight.
The long-term study data reinforced this. Participants who showed the expected age-related decline in slow-wave activity over the four-year follow-up also showed increased anxiety at their second visit.
The brain mechanism behind the connection
Brain imaging revealed why this might be happening. Atrophy in emotion-processing regions of the brain was associated with reduced slow-wave generation. These are the same regions that tend to shrink with age and that are implicated in cognitive decline.
But when researchers analyzed the mechanism behind this change, impaired slow-wave activity fully accounted for the relationship between brain atrophy and next-day anxiety.
This means it wasn't the atrophy itself that was driving anxiety. It was the fact that atrophy reduced the brain's capacity to generate the slow waves needed for overnight emotional regulation.
This suggests that even in the presence of age-related brain changes, intact deep sleep may preserve emotional stability by rescuing the brain's nightly recalibration process.
How to protect your deep sleep as you age
Since slow-wave sleep appears to play such a critical role in overnight anxiety regulation, protecting this phase of sleep becomes especially important as you get older. Here are some evidence-backed strategies for getting a better night's rest:
- Manage stress during the day, not just at bedtime: Research shows that daytime stress can shift your sleep architecture away from deep sleep and toward lighter stages. Building in recovery time throughout the day may help preserve your slow-wave sleep at night.
- Keep a consistent sleep schedule: Your brain's ability to generate slow waves is tied to your circadian rhythm, the internal body clock that regulates sleep cycles. Going to bed and waking up at roughly the same time each day supports the biological processes that produce deep sleep.
- Prioritize physical activity: Exercise has been shown to increase slow-wave sleep, particularly when done consistently. Even moderate activity like walking can make a difference.
- Limit alcohol close to bedtime: While alcohol may help you fall asleep faster, it fragments sleep architecture and suppresses slow-wave activity later in the night.
- Consider magnesium: This mineral supports GABA, a neurotransmitter involved in sleep regulation. Low magnesium has been associated with trouble falling and staying asleep. We love this magnesium powder with 230 milligrams of mg and tart cherry.
The takeaway
This research is one more reminder that prioritizing sleep is always a good idea. Plus, it may work as an emotional resilience strategy as you age.
If you feel like anxiety is getting harder to shake as you age, think about whether sleep might be part of the equation and how you can optimize your sleep schedule.
