Many of us love to use the weekend as a time to sleep in and catch up on rest from a long week; however, new research suggests that sleeping in may not make up all the hours of sleep you lost during the week.

According to a new study, which was published in the American Journal of Physiology- Endocrinology and Metabolism, using the weekend to catch up on sleep may not actually reverse all of the damage that was caused by missing out on sleep during the week. During this study, researchers monitored the sleep schedules of thirty health adults. For this study, each participant was put on a 13-day schedule, which included four nights of normal eight hour sleep cycles, six nights of waking up two hours earlier than the previous cycle, and then three nights for a full ten “recovery” hours.

During the sleep sessions, researchers conducted tests to track alertness, kept tabs on inflammatory and stress hormone levels with blood samples, and monitored brain waves. Within five days of losing sleep, researchers found that most of the men and women were sleepy, could not concentrate as well on their attention tests, and had an increased amount of interleukin-6 levels in their blood. Interleukin-6 levels are inflammation agents in the body. However, once the participants were able to recover with extra sleep for two days, they performed better on tests, they were not as drowsy, and saw a decrease in interleukin-6 levels. Although the participants’ alertness improved, the group as a whole did not see an improvement on the attention tests.

While these researchers say that extended sleep helps to a certain extent, other studies have linked sleeping an average of ten or more hours a day with chronic diseases including anxiety, obesity, and diabetes. Researchers suggest keeping a regular sleep schedule in order to maintain the timing of a body’s internal clock and to help you wake up and fall sleep more easily.