Taking a siesta in the middle of the day seems to reduce the risk of death from heart disease, particularly in healthy young men. This conclusion on the benefits of a siesta is suggested by a survey of a general population sample of 23 681 people, who at enrolment had no history of heart disease, stroke or cancer. As well as recording napping habits, researchers asked about diet and exercise so as to allow for these additional variables.
It was found that those who occasionally napped, had a 12% lower rate of coronary mortality, whilst those who regularly napped for 30 minutes at least three times per week, had a 37% lower rate. The association was especially strong among men working at the start of the six year study: they showed a 64% reduced risk.
(Siesta in Healthy Adults & Coronary Mortality in the General Population. Archives of Internal Medicine, February 2007.)