Everyone knows that sleep is important factor for both mental and physical health. Proper sleep also enables you to be fully functional during the daytime. Sleep disorders (including difficulty falling asleep at night, poor sleep quality, early waking, circadian rhythm disorders) can be caused by many reasons i.e. stress, depression, anxiety, poor diet or an imbalance of chemical messengers and hormone in the brain namely serotonin and/or melatonin. The consequence of sleep disorders is often daytime fatigue.