You may be too exhausted even to manage your daily affairs. In most cases, there's a reason for the fatigue. It might be allergic rhinitis, anemia, depression, fibromyalgia, chronic kidney disease, liver disease, lung disease (COPD), a bacterial or viral infection, or some other health condition.

Why am I tired after sleeping enough?

SUMMARY: Inadequate or poor-quality sleep is a common cause of fatigue. Getting several hours of uninterrupted sleep allows your body and brain to recharge, allowing you to feel energized during the day.

What are you lacking when you feel tired?

Vitamin deficiency

Being tired all the time can also be a sign of vitamin deficiency. This could include low levels of vitamin D, vitamin B-12, iron, magnesium, or potassium. A routine blood test can help identify a deficiency. Your doctor may recommend taking supplements.