Interrupted, fragmented sleep is as bad for your body as not sleeping at all, according to a study published in the journal Sleep Medicine in May.
Researchers at Tel Aviv University’s School of Psychological Sciences in Tel Aviv, Israel, studied students who wore wristwatches that monitored when they were awake and asleep. On one night, the students were allowed to sleep for eight hours. The next night, the students were awakened by four phone calls, each instructing them to complete a task on a computer before going back to bed. On both mornings, the students were given tests to measure their brain function and emotional state.
After just one night of disturbed sleep, students showed shorter attention spans, reduced cognitive abilities and more negative moods, similar to those found in people who haven’t slept at all.
The problem of interrupted sleep is particularly troublesome for new parents and people in certain professions, such as hospital physicians, says study author Dr. Avi Sadeh, who directs a sleep clinic at the university.