More than a third of Americans regularly sleep less than seven hours a night, affecting their ability to concentrate, according to the Centers for Disease Control and Prevention.

Short sleep duration was found among 35 percent of adults surveyed, and 48 percent reported snoring, an unhealthy behavior, according to a study in the journal Morbidity and Mortality Weekly Report yesterday. About 39 percent of respondents aged 25 to 54 reported sleeping less than seven hours in a day.

“Poor sleep habits, which include not scheduling enough time for sleep, can be assessed during general medical care visits and improved with effective behavioral changes,” the authors wrote in an editorial following the study by the Atlanta-based CDC.

The duration study is the first to examine prevalence of unhealthy sleep behaviors, the authors wrote.