A new research from South Korea has found that having too much or too little sleep may lead to hardening of arteries, which could be an early indication of heart disease. Men and women who had 9 or more than that hours of sleep per night and the ones who had slept five hours or lesser per night had more calcium deposition in their arterial walls and stiffer arteries in comparison to those who had slept 7 hours a night.

As per the researchers, sleep quality is also very important. The ones who have said that they were not able to have good sleep were at increased risk of facing two early signs of heart disease than those who slept better.

In the study, the researchers recruited more than 47,000 men and women who were aged on an average 42. They were asked to complete a questionnaire with regard to sleep. They have also undergone tests to detect lesions of calcium and plaque in their artery leading to the heart, an early sign of disease.

The questionnaires unveiled that the participants had average sleep duration of 6.4 hours and around 84% said their sleep quality was good. The research studied those who were sleeping more and less.

The ones who were sleeping less were having 50% more calcium in their coronary arteries than the ones who slept for seven hours per night. People have long sleep had 70% more calcium than those who slept seven hours.