Believe it or not there are a large number of people that feel sleepy all day even though they have slept well through the night. If you are always tired and you don’t know what is causing it then you need to understand the various reasons that might be making you feel this way. If you are wondering how you can figure out what are the main reasons why you are feeling so sleepy all the time then here is what you need to do.In case you haven’t checked your blood sugar make sure you get all your routine blood tests done to make sure you do not have any problems or conditions that could be causing you to feel sleepy. Conditions such as thyroid, anemia and diabetes could cause you to feel very sleepy all day even though you have slept well through the night. Medication can help you keep these conditions under control and help you feel more active and energetic all day. People with high blood sugar levels often feel very sleepy and once you find out why you are feeling sleepy all you need to do it consult a doctor who can give you the right medical treatment.Another reason why people feel really sleepy all day even though they sleep well at night is because they are depressed. Depression makes you feel very tired and does not make you want to get out of your home even though you have slept all day and night. Problems in your relationship personally or at work could be one of the leading causes of depression and in case you are sad about something and you do not know how to deal with it, the best way is to consult some professional and get assistance that will help improve your mindset.