Too much sleep might be worse for your brain than too little

An analysis of 69 studies reveals that oversleeping may raise dementia risk even more than undersleeping.

 

Your brain has a surprisingly narrow sleep window Most people worry about not getting enough sleep. Few consider that getting too much might be worse. A new meta-analysis published pooled data from 69 studies and found that sleeping more than 8 hours a night was associated with a 28% increase in dementia risk, higher than the 18% increase linked to sleeping less than 7 hours. The sweet spot: 7 to 8 hours a night. “Consistently sleeping outside the 7-to-8-hour range, in either direction, may carry long-term implications for brain health,” said lead author Akinkunle Oye-Somefun, PhD, of York University. Sleep was not the only factor. Regular physical activity correlated with a 25% reduction in dementia risk, a consistent finding across 49 studies and across age groups, including people in their 50s and 60s. And sitting for more than 8 hours a day increased risk by 27%, independent of how much someone exercised. For more on the sleeping sweet spot and the importance of physical activity, jump to “Getting too much or too little sleep may increase dementia risk as much as 28%.” Also making headlines this week: 🩸 New blood test uses gut health to predict cognitive decline years earlier 💊 Beta-blockers: 1 year of treatment may be enough after heart attack 🧬 FDA approves Wegovy-like GLP-1 pill, Foundayo, for weight loss We love to hear from you, so please email us if you have any feedback, comments, or questions about this weekend’s Sunday Supplement. Stay informed and stay healthy! Tim Snaith Newsletter Editor, Medical News Today

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