11-hour days are bad for the heart

LONDON (Reuters) - People working 10 or 11 hours a day are more likely to suffer serious heart problems, including heart attacks, than those clocking off after seven hours, researchers said on Tuesday
The finding, from an 11-year study of 6,000 British civil servants, does not provide definitive proof that long hours cause coronary heart disease but it does show a clear link, which experts said may be due to stress.

In all, there were 369 cases of death due to heart disease, non-fatal heart attacks and angina among the London-based study group -- and the risk of having an adverse event was 60 percent higher for those who worked three to four hours overtime.

Working an extra one to two hours beyond a normal seven-hour day was not associated with increased risk.

More fundamentally, long hours may be associated with work-related stress, which interferes with metabolic processes, as well as "sickness presenteeism," whereby employees continue working when they are ill.