Research by the British United Provident Association (Bupa) shows a quarter of staff are working longer hours because they worry they may lose their job.
Concerns over health are being raised as one in three people who are worried about job security are losing sleep, while one in five say they are depressed.
Dr Rebecca Small, assistant medical director for Bupa UK Health Insurance, said employers have to try and spot the signs of employee stress early.
"Offering counselling services in the workplace like employee assistance programmes can help enormously," she added.
The survey also revealed 39 per cent of those working in Bristol and Birmingham are worried about job security compared to the national average of 34 per cent.
In recent news, the On Site Massage Company advised employers to allow their workers to have massages in the workplace to ease their stress.
