Quality of your sleep is more important than the quantity of it. Nidra (sleep) is considered to be one of the three pillars of healthy living, along with Ahaara and Brahmacharya. As per Ayurveda, there is no fixed amount of time that a person should sleep, for proper health e.g. minimum of eight hours of sleep etc. If a person goes to sleep on time; has a sound sleep, devoid of any kind of dreams or nightmares and feels fresh on waking up; then the person is considered to have had a healthy sleep.
@drshrinidhnair