Question of the Day

The effects of sleep loss are subject to a number of popular misconceptions. The belief that everyone must sleep 8 hours a night is a myth. According to the results of a recent survey on the subject, adults average about 7 to 7.5 hours of sleep per night, and many individuals function effectively with 5 to 6 hours of sleep. In fact, 20 per cent of the population (slightly more in men) sleep less than 6 hours per night. Another important fact is that sleep time decreases with age.

It is implied in the passage that a sleep time under 8 hours ________.