– Suspect you're not getting enough sleep? You can now verify whether that is indeed the case. In a study published last month in the journal Sleep, researchers claim to have determined exactly how much sleep we need: 7.6 hours for women and 7.8 hours for men. The findings arose from a quest to look at the optimal amount of sleep needed to reduce the risk of "sickness absence." To get to those findings, researchers followed 3,760 Finnish participants over a seven-year span and compared their sleep disturbances (such as early morning awakenings and use of sleeping pills) with data on illness-related work absences provided by the country's Social Insurance Institution. They then adjusted for a slew of things, like working conditions and education, and arrived at their figures, noting "direct costs due to sickness absence could decrease by up to 28% if sleep disturbances could be fully addressed." MarketWatch cites a 2013 Gallup poll that found 40% of Americans don't make it to the seven-hour mark; the average amount of sleep was 6.8 hours. That's actually slightly up from the 6.7 hours poll-takers reported to Gallup in 1990 and 2001, but a big drop from how we lived decades ago: In 1942, the average was 7.9. But other recent research suggests the magic amount of sleep might actually be closer to seven hours than eight. Which figure to go with? The CDC might be able to help; it plans to issue new guidelines, possibly as soon as next year. (In other sleep news, find out why you should nap after coffee.)