Oversleeping!!

Many students get oversleeping, and it makes them not to concentrate when studying. I try to find the causes of the overslepong in the site  http://www.buzzle.com , and here is the result, I just take two causes:
Causes of Oversleeping 
Depression:  Oversleeping during depression is not healthy. Instead, one should establish regular and adequate sleeping hours to get over depression. Because, side effects of sleeping too much can add further mental stress on the person. Lack of motivation is also among mental causes of heavy sleep.

Poor Diet: A poor diet or eating little amount of food can make a person feel tired and sluggish. Eating unhealthy or junk food can lead to drowsiness and one might feel like napping after a heavy meal. Hence, one needs to eat a diet rich in nutrients and include lots of fresh fruits and vegetables in their diet and reduce the amount of junk food and greasy food.