According to a British study involving nearly 10,000 subjects, going to work while you are sick—even with just a cold, is dangerous. It actually increases the risk of heart disease. The stress of going to work while sick actually increases the risk of heart disease. The University College London team compared attendance rates with the health records of 10,000 civil servants over a 10 year period and found 30% to 40% of those who did not take time off when ill had double the incidences of coronary disease  during the 10-year study.

The reason for the higher rate of heart disease is stress. Paul Sellers, a policy officer at the Trades Union Congress said, “Some people, particularly in jobs that involve long hours, feel compelled to come to work as promotion is directly linked to how long you spend in the office.” Professor Sir Michael Marmot, the head of the study, said workers did not realize the damage they were doing.