A study has found that night owls may have a higher risk of dying sooner than early risers. The extent of this increased risk is reported to be around 10% higher in one account, but the underlying causes are unclear, with some suggestions that factors such as alcohol and tobacco use, rather than sleep habits, may be to blame. The relationship between being a night owl and the risk of early death appears to be supported by multiple reports, although the specifics of the link are not fully explained.