It doesn’t matter if I sleep a full eight hours or struggle through a meagre five ― I’m always groggy, confused and sleepy first thing in the morning.

That’s not just because most women need more sleep than men, it seems. According to The Sleep Foundation, I might be dealing with sleep inertia.

The phenomenon, which can make you disoriented, drowsy and uncoordinated, has no known cause.

But experts think it could happen when a person is woken during non-REM sleep, due to changes in blood flow, or because of higher levels of adenosine.

Some speculate it helps to protect sleep that........

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