It is good to be hard working, but in a limit, as a new study has found that long working hours increase risk of coronary heart disease and stroke. People who work 55 hours a week have a 33% increased risk of stroke and 13% increased risk of coronary heart disease in comparison to those who work standard hours.

The study, which is the largest when it comes to the relationship between working hours and cardiovascular health, has based its findings on the analysis of data having more than 600,000 individuals in Europe, the United States and Australia.

Prof. Urban Janlert from Umea University in Sweden said that it is in this study they have come to know that stroke can happen due to long working hours.

In addition to the analysis of data, the researchers have also complied unpublished information from public databases. They even asked for additional data and there were 17 studies of stroke, which included 528,908 men and women who were tracked for average 7.2 years.

During the observation period, some 1,722 non-fatal and deadly strokes were recorded. Study researchers controlled many factors including smoking, physical activity and high blood pressure and cholesterol.

The researchers came to know that there was a one-third increased risk of stroke among people who work 55 or more hours weekly in comparison to those who work for 35 to 40 hours. Risk of coronary heart disease was found after assessing 25 studies involving 603,838 people.