There is a plethora of reasons that disturb sleep disorder or nigh mare for most people. Among them the main causes may be anxiety due to internal or external problems, over consumption of addicted food or liquid and nature of work. Firstly, some people suffer from insomnia due to over thinking about something despite the condition is not frivolous, but others wary about the family problems, issues from work. Consequently, they could achieve sound sleep due to abnormal sleeping pattern in long term.
In addition, most students eat or drink some addicted food or liquid such as coffee or tea, energy drink, salad of tea leaves. The effects of consumption this kind of snack foods lead to insomnia, therefore, even if they finish their study, they may have a bad habit of sleeping disorder.
Finally, employees or freelancers such as bus driver, security, nurses or doctors, writers suffer from serious problems about sleeping due to their work nature. In long term, although they are leaving this type of job, they could still have a sense of dissatisfaction of sleep due to not having sufficient number of sleeping hours.
However, as sleeping imbalance is not a kind of disease, people could adjust to have satisfied either by taking some medicines such as melatonin or other vitamins, or by treating with healthy balance diet.