Sleeping for less than seven hours a night may increase the risk of fatal heart disease, a new study has warned.
A good night's sleep can increase the benefit of exercise, healthy diet, moderate alcohol consumption and non-smoking in their protection against cardiovascular disease (CVD), according to results of a large population follow-up study.
Results showed that the combination of the four traditional healthy lifestyle habits was associated with a 57 per cent lower risk of cardiovascular disease (fatal and non-fatal) and a 67 per cent lower risk of fatal events.
But, when "sufficient sleep" - defined as seven or more hours a night - was added to the other four lifestyle factors, the overall protective benefit was even further increased - and resulted in a 65 per cent lower risk of composite CVD and a 83 per cent lower risk of fatal events.
"If all participants adhered to all five healthy lifestyle factors, 36 per cent of composite CVD and 57 per cent of fatal CVD could theoretically be prevented or postponed," researchers said.
The study is the first to investigate whether the addition of sleep duration to the four traditional healthy lifestyle factors contributes to an association with CVD.
In the Monitoring Project on Risk Factors for Chronic Diseases (MORGEN), a prospective cohort study in the Netherlands, 6672 men and 7967 women aged 20-65 years and free of CVD at baseline were followed up for a mean time of 12 years.
As expected, results showed that adherence to each of the four traditional lifestyle factors alone reduced the risk of CVD, researchers said.
Those at baseline who recorded sufficient physical activity, a healthy diet and moderate alcohol consumption reduced their risk of composite CVD from 12 per cent for a healthy diet to 43 per cent for not smoking and risk reduction in fatal CVD ranged from 26 per cent for being physically active to 43 per cent for not smoking.
However, sufficient sleep duration alone also reduced the risk of composite CVD by about 22 per cent and of fatal CVD by about 43 per cent.
Thus, non-smoking and sufficient sleep duration were both strongly and similarly inversely associated with fatal CVD.
These benefits were even greater when all five lifestyle factors were observed, resulting in a in a 65 per cent lower risk of composite CVD and an 83 per cent lower risk of fatal CVD.
The study was published in the European Journal of Preventive Cardiology.