Maintaining proper sleeping habits may increase a woman’s longevity, according to a study published in the journal Sleep Medicine.

For this trial, researchers from University of California – San Diego (UCSD) analyzed results of a four-year study conducted from 1995 to 1999, which included 459 women. During the research, each participant’s sleep duration was measured with a wrist activity monitor.

Of the group, a total of 358 women participated in follow-ups, while researchers found that a total of 86 individuals had passed away. As a result, those who slept between six-and-a-half and seven-and-a-half hours per night had the lowest mortality rate. Also, the team found that women who slept less than five hours were more likely to suffer from fatal health complications.

Furthermore, these findings showed that obstructive sleep apnea, especially in older women, was not linked to an increased risk of death.

Daniel F. Kripke, lead author of the study, stated that results show that “women who sleep as little as five to six-and-a-half hours have nothing to worry about since that amount of sleep is evidently consistent with excellent survival.”

According to the Centers for Disease Control and Prevention, each year an estimated 70 million people in the U.S. have been diagnosed with sleeping disorders or suffer from irregular sleep patterns.