You’re tired because…you have sleep apnea
If you have sleep apnea, your throat starts to close when you’re asleep, which is why people with the condition tend to snore. Not getting enough oxygen sounds scary, but your brain won’t let you suffocate. “Sleep apnea prevents you from going into the deep restorative stages of sleep, so people are unable to get rested and fall asleep frequently during the day,” explains Dr Teitelbaum. “Falling asleep easily during the day with a shirt collar size over 42 centimetres, high blood pressure, being overweight and snoring tell you that you should check for sleep apnea.”
You’re tired because…you have heart failure
When you have heart failure, your heart can’t keep up with the body’s needs for blood. Your body will start to bring blood away from body tissues so it can keep vital organs fully supplied. With less blood in your leg muscles, even everyday activities can feel exhausting. Plus, fluid gets backed up in your veins leading away from your lungs. This increases pressure and allows fluid to leak into the lungs, making you lose your breath suddenly. When you’re asleep, it could wake you up and make for a restless night.
You’re tired because…you have hypersomnia
Heneghan says oversleeping may be a sign of hypersomnia, a chronic neurological condition where you’re tired no matter how much sleep you get. According to the US Hypersomnia Foundation, you may have this condition if you’re tired during the day no matter how much sleep you get at night. The condition usually crops up in adolescence or early adulthood and can seriously affect sleep quality, as well as your ability to function during the day.