If you do not sleep many hours a day, you have every reason to worry. Short sleep duration is often associated with chronic diseases with age. Now researchers are getting specific information after analyzing data collected over 25 years.

They found that people over 50 need at least 5 hours of sleep to reduce their risk of chronic health problems.

The study, published in Plos Medicine, looked at more than 7,000 subjects in the UK aged at least 50 who did not have chronic diseases. Of these, during a median follow-up of 25 years, 213 died without developing any chronic disease, 4,446 developed one disease, and of these 2,297 developed a second disease and 787 died.

Researchers say there is a link between sleeping less than five hours in the 50s, 60s and 70s with a higher risk of developing many chronic diseases. The connection with the duration of sleep over 9 hours was observed only when measuring at the age of 60 and 70 years.

The analyzed data showed that 50-year-old people who slept less than five hours a day had a higher risk of developing a chronic disease first, and then another, than those who slept 7 hours a day. Sleeping more than seven hours at age 50 was not associated with such a transition.

However, in those with chronic illnesses, there is some evidence that sleeping more than nine hours may be associated with a higher risk of another illness.

So, according to researchers, ideally we should sleep about eight hours if we want to be healthy, but the minimum is five hours.

Source: Study published in Plos Medicine by Severin Sabia, Aline Dugravo, Damien Leger, Celine Ben Hassen, Mika Kivimaki, Archana Singh-Manu