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Catching up on sleep at the weekend did not undo the metabolic effects of short weeknights in a 2019 laboratory study. One group slept five hours a night; another had five short nights, two free weekend nights, then two more short nights. The weekend group still gained weight and lost insulin sensitivity, and some measures were worse.

Depner et al., Current Biology, 2019

HealthScience

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The study, run in a sleep laboratory at the University of Colorado, mimicked a common real-life pattern: short sleep on workdays and extra sleep at the weekend. Insulin sensitivity measures how well the body responds to insulin, the hormone that clears sugar from the blood after eating; when it drops, blood sugar runs higher than it should, which over time raises the risk of type 2 diabetes. The recovery group did sleep in and snack less at night over the weekend, but those gains reversed as soon as short nights resumed, and some measures ended up worse than in the group that never got extra sleep. The findings challenge the popular idea that weekend lie-ins can cancel out a week of short sleep.

Türkçe oku
2019'da yapılan bir laboratuvar çalışmasına göre hafta sonu uykuyu telafi etmek, hafta içindeki kısa gecelerin metabolizmaya etkisini ortadan kaldırmıyor. Bir grup her gece beş saat uyudu; öbür grup beş kısa geceden sonra hafta sonu iki gece istediği kadar uyudu, ardından iki gece daha beş saatle yetindi. Hafta sonu uyuyan grup da kilo aldı, insülin duyarlılığı düştü; bazı ölçümlerde durumu daha da kötüydü.

Çalışma Colorado Üniversitesi'nin uyku laboratuvarında yapıldı ve birçok kişinin gerçek hayatta yaşadığı düzeni taklit etti: hafta içi kısa uyku, hafta sonu telafi. İnsülin duyarlılığı, vücudun yemekten sonra kandaki şekeri temizleyen insülin hormonuna ne kadar iyi yanıt verdiğini gösterir; bu duyarlılık düşünce kan şekeri olması gerekenden yüksek seyreder ve zamanla tip 2 diyabet riski artar. Telafi grubu hafta sonu geç kalktı ve geceleri daha az atıştırdı; ama kısa geceler başlar başlamaz bu kazanımlar kayboldu, hatta bazı ölçümler hiç telafi yapmayan gruptakinden kötü çıktı. Bulgular, hafta sonu uzun uyumanın bir haftalık uykusuzluğu silebileceği yönündeki yaygın inancı sarsıyor.

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