More than 9 hours of sleep? Science says your memory may suffer

If you've ever felt proud of clocking in over nine hours of sleep, thinking it's the ultimate health hack, recent research suggests you should reconsider. A study from the University of Texas Health Science Center reveals that excessive sleep, specifically more than nine hours per night, may be linked to poorer cognitive performance, especially in individuals experiencing symptoms of depression.

The study analyzed data from nearly 2,000 dementia-free adults aged 27 to 85, focusing on sleep duration and cognitive function. Dementia is a term for several diseases that affect memory, thinking, and the ability to perform daily activities.

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The findings indicated that participants who slept longer than nine hours exhibited decreased memory, visuospatial abilities, and executive functions. These effects were more pronounced in individuals with depressive symptoms, regardless of whether they were on antidepressant medication.

Vanessa Young, a clinical research project manager at the Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases, stated that sleep could be a modifiable risk factor for cognitive decline in individuals with depression.

This research suggests that those with mental health conditions should be more serious about their sleep; they might need personalized sleep recommendations. While sleep is essential for brain health, both insufficient and excessive sleep can have detrimental effects. The Global Council on Brain Health recommends 7 to 8 hours of nightly sleep for adults to preserve cognitive function.

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It's crucial to pay attention to your sleep patterns and consult healthcare professionals if you experience persistent changes in sleep duration or quality, especially if accompanied by depressive symptoms. People who work shifts might be more vulnerable, as their sleeping cycle is often disrupted by work. Balancing sleep duration could be a key factor in maintaining cognitive health and overall well-being.