Work-related stress is costing businesses £70 million and 6.5m days off sick every year, new research revealed today.

Almost 150,000 workers have taken at least a month off because of stress-related illness.

Those hit hardest by high levels of stress are workers aged between 35 and 44, reported a survey by the Health & Safety Executive.

HSE official Elizabeth Gyngell said: "Stress is a huge occupational health problem, inflicting a heavy toll both in terms of financial cost and human suffering."

Teachers and nurses are the worst hit by stress while window cleaners are the least affected