New research shows that regularly sleeping nine hours or more may harm cognitive performance, especially for those experiencing depression. Aim for 7–8 hours of quality sleep to support brain health and mental wellbeing. If you’re concerned about your sleep or mood, don’t hesitate to seek support and track your brain fitness. Want to learn more about how sleep duration affects your brain and what it means for mental health? Read the full article to discover practical tips for optimising your sleep and protecting your cognitive wellbeing.
Can You Get Too Much Sleep? New Research Links Long Sleep to Poorer Brain Health—Especially in Those with Depression
We often hear about the dangers of not getting enough sleep, but could sleeping too much also be a problem for your brain? According to a recent study led by researchers at UT Health San Antonio, regularly sleeping nine hours or more per night is linked to poorer cognitive performance—and the effect is even more pronounced for people experiencing depression.
What Did the Study Find?
The research team analysed data from 1,853 adults aged 27 to 85, all free from dementia and stroke, as part of the well-known Framingham Heart Study. They discovered that those who reported longer sleep durations (nine hours or more per night) performed worse on tests of memory, visuospatial skills, and executive functions (such as planning and problem-solving). Importantly, these negative effects were strongest in individuals with symptoms of depression, regardless of whether they were taking antidepressants.
Why Does This Matter?
We know that sleep is essential for brain health, but this study highlights that both too little and too much sleep can be problematic. The Global Council on Brain Health recommends 7 to 8 hours of sleep per night for adults to support optimal cognitive function. Both excessive and insufficient sleep have been linked to difficulties with memory, attention, and mental flexibility.
Depression and sleep disorders often go hand-in-hand—about 90% of people with depression report sleep problems. This study suggests that for those with depression, getting too much sleep may be a modifiable risk factor for cognitive decline.
Practical Tips for Brain Health
Aim for 7–8 hours of sleep per night: This is the sweet spot recommended for most adults to maintain cognitive health.
Monitor your sleep patterns: If you regularly sleep more than nine hours and still feel tired or notice changes in memory or focus, it may be worth discussing with a healthcare professional.
Address mental health concerns: If you’re experiencing symptoms of depression, seeking support can help improve both your mood and your sleep quality.
Track your brain fitness: Wearable neurotech, such as our fNIRS-based headset, can help you monitor cognitive performance and spot patterns related to sleep and mental wellbeing.
The Bottom Line
Getting enough sleep is vital for brain health, but more isn’t always better. If you or someone you know is struggling with depression and sleeping excessively, it’s important to pay attention to changes in cognitive function and seek support if needed. As always, a balanced approach to sleep, mental health, and brain fitness is key to long-term wellbeing.