It’s been proven time and time again that working long hours has certain benefits. First of all, your hard work and dedication can likely earn you a promotion or two, as well as better pay. Those who work longer hours are typically categorized as go-getters, not afraid to get their hands dirty and do what needs to be done. And employers like those characteristics.

However, recent studies are showing that long hours spent working may be quite detrimental to your heart health. And the more days you work long hours, the higher your risk is for a stroke.

This comes from a recent study conducted in France. 144,000 French men and women between the ages of 18 and 69 reported findings on their heart health and work habits. A focus was placed on those who had been in the workforce for at least six months, of whom most were full-time employees.

About 30% of French participants reported working for long hours, which means 10 hours a day or more for at least 50 days of the year. And about 10% said they worked for long hours for ten years or more. Those who had survived a stroke after taking on long work hours amounted to be about 1% of participants.

It was found that those who reported working long hours were 29% more likely to have a stroke, and those who worked long hours for at least ten years had a 45% greater risk of stroke.

Study author Dr. Alexis Descatha says, “Previous studies in South Korea, the USA, and Europe have raised this issue…, but for the first time we had data to show an association with duration, (meaning) 10 years or more.”

Descatha is a professor in occupational health with the French National Institute of Health and Medical Research (Inserm) and a specialist in emergency medicine at Paris Hospital in Versailles.

Each participant, in addition to reporting their work habits and heart health through questionnaires, also agreed to medical interviews which collected body mass index (the standard used to measure obesity/overweight), past stroke histories, family history of heart disease, and status of high blood pressure and diabetes.

The result of the study gave the team rather “unexpected” findings, as it showed that not only do long hour work routines affect stroke risk but also that those with higher risk were people under age 50.

Descatha and his team have decided that more research is needed to understand why it seems to affect younger people more than the expected older generations. He believes it might be, at least in part, due to the overall impact of such work. Irregular schedules, stress, and general working conditions that go along with long working hours could have more of a negative effect on younger people than the more common factors that lead to poor heart health, such as high blood pressure and obesity, which are more associated with older men and women.

These findings and the rest of Descatha’s research is outlined in the July Issue of Stroke, a medical journal.

Director of the Ahmanson-UCLA Cardiomyopathy Center and co-director of UCLA’s preventative cardiology program Dr. Gregg Fonarow adds that “a variety of potential mechanisms have been considered as helping to explain this excess risk.”

He says, “These include long hours spent working leading to less daily physical activity, prolonged sitting, greater exposure to stress, and disruptions in sleep.” And that “it has also been suggested that those with long work hours may pay less attention to their cardiovascular health or seek attention for concerning symptoms.”