Sleeping in on the weekends doesn’t fix all the deficits caused by workweek sleep loss. A few days of lost sleep can have adverse effects including increased daytime sleepiness, worsened daytime performance, an increase in molecules that are a sign of inflammation in the body and impaired blood sugar regulation. Recovery sleep over a weekend may not reverse all the effects of lost sleep during the week and if it disrupts your normal go-to-bed and get-up routine that could also impact on sleep quality.