To maintain good health, an adult generally needs 7+ hours sound sleep each night. However, this time period depends on various other factors also e.g. quality of sleep, daily activities and overall health. If sleep is sound, then its ok, but if it faces some breaks in between, then the period of sleep increases. Or if an adult takes long time to start sleeping, even then sleep time will increase.
Sound sleep is necessary for maintaining good health. So improve your sleep and make sleep priority.