According to a survey conducted by Canada Life Group, employees said they worry about their colleagues judging them if they do not come to office, Daily Mail reported.
It was found heavy workload was a significant reason for a fall in sick days.
Canada Life Group Insurance is one of Britain's largest group-risk insurance companies.
Employees said being aware that work would build up in their absence put them off staying at home.
A third of workers surveyed said they would go to work if they had the flu, and 93 percent said a cold was not a good enough reason to stay at home.
"It is worrying to see that so many employees feel they cannot take a day off," said Paul Avis, from Canada Life Group.
Other than witnessing a heavy workload that would build up while they were off, fear of judgement by colleagues and the risk of losing their job were also selected as major reasons for going to work when sick.
The British economy has been on a plateau since the 2008 financial crisis, with small spurts of growth and contraction.
As a result, British unemployment has risen from only five percent in 2007 to just under eight percent, well below the double-digit rates scaled during recession in the 1990s.