Why do I feel tired after eight hours of sleep?

Eight hours in bed does not always equal eight hours of restorative sleep. Your sleep may be interrupted by noise, stress, alcohol, pain, temperature, bathroom visits or breathing problems. You may also need slightly more than eight hours, or your sleep schedule may be out of line with your natural body clock. Conditions such as sleep apnea, insomnia, restless legs, anemia, thyroid disorders and depression can also cause fatigue. Irregular bedtimes and waking during deep sleep may contribute to temporary grogginess. Keep a sleep diary and review your routine, caffeine use and alcohol intake. If tiredness continues for several weeks, affects daily life or occurs with loud snoring, choking or morning headaches, seek medical advice.