Poor sleep habits associated with faster aging of the brai

By Admin

01 Oct, 2025

Sleep is often called the brain’s reset button, but new research shows just how crucial it is for healthy aging. According to a comprehensive brain imaging study from Karolinska Institutet, published in the journal eBioMedicine, people who sleep poorly are more likely to have brains that appear older than their actual chronological age. The findings suggest that increased inflammation in the body may partly explain this accelerated brain aging.

Poor Sleep and Dementia Risk

Poor sleep has long been linked to dementia, though it is not clear whether sleep problems contribute to its development or are early warning signs of the disease. To better understand the connection, researchers at Karolinska Institutet examined how different sleep characteristics impact brain aging.

The study analyzed data from 27,500 middle-aged and older adults in the UK Biobank who underwent brain MRI scans. Using advanced machine learning models, the team estimated biological brain age based on over a thousand brain MRI phenotypes.

Measuring Sleep Quality

Participants’ sleep quality was scored on five self-reported factors:

• Chronotype (morning vs. evening preference)
  
  

• Sleep duration
  
  

• Insomnia
  
  

• Snoring
  
  

• Daytime sleepiness
  
  

They were grouped into three categories:

• Healthy sleep (≥4 points)
  
  

• Intermediate sleep (2–3 points)
  
  

• Poor sleep (≤1 point)
  
  

The study found that those with poor sleep showed a higher likelihood of having an older-looking brain compared to their peers with healthier sleep patterns.

The Role of Inflammation

To understand why poor sleep affects brain aging, researchers also studied low-grade inflammation in participants. Results revealed that inflammation accounted for just over 10% of the link between poor sleep and accelerated brain aging.

“Our findings provide evidence that poor sleep may contribute to accelerated brain aging and point to inflammation as one of the underlying mechanisms,” explains Abigail Dove, one of the lead researchers. “Since sleep is modifiable, it may be possible to prevent accelerated brain aging and perhaps even cognitive decline through healthier sleep.”

Other Possible Explanations

Beyond inflammation, scientists suggest other pathways that might explain the association:

• Disruption of the brain’s waste clearance system, which is most active during sleep.
  
  

• Poor sleep’s negative impact on cardiovascular health, which in turn harms the brain.
  
  

Study Limitations

While the study offers valuable insights, it has some limitations. Participants in the UK Biobank tend to be healthier than the general population, which may affect the generalizability of results. Additionally, sleep quality was self-reported, which can sometimes introduce inaccuracies.

A Path Toward Healthier Aging

Despite these limitations, the research underscores the importance of prioritizing sleep as a lifestyle factor that could slow down brain aging. The collaborative study involved experts from the Swedish School of Sport and Health Sciences, Tianjin Medical University, and Sichuan University, with funding from organizations such as the Alzheimer’s Foundation, Dementia Foundation, Swedish Research Council, Loo and Hans Osterman Foundation, and the Knowledge Foundation.

As science continues to uncover the intricate links between sleep and brain health, one message is clear: a good night’s sleep is not just rest it’s protection for the brain’s future.