Email and phone messages damage health and make staff tired and less efficient, according to a report by top psychologists. Just four phone calls or emails an hour increased heart rate levels, the study of office staff in Holland and Russia found. Although workers speeded up their other tasks to compensate for these distractions, many skipped more menial, but necessary, tasks. This could lead to important safety checks being missed in certain work places. Constant interruptions were also detrimental to health. Staff had raised heartbeats and felt less cheerful and easygoing, according to today’s Daily Mail. Dutch professor Dr Fred Zijlstra, in charge of the report, said: "These daily hassles have more effect than we realise. "On a superficial level, their moods were affected by interruptions. They were less happy and less optimistic. But these things are an indication of fatigue." Dr Zijlstra added: "There was an effect every time their phone rang, but also we saw a general change towards them having a higher heart rate." 70 volunteers were monitored in the experiments. They were given text-editing tasks and interrupted by phone calls, increasing to around four per hour. Each call asked them to do an extra task, increasing their workload. The volunteers then hurried to complete their main work, but ignored day-to-day necessities such as checking the ink in printers or paper in fax machines. Dr Zijlstra said this could have serious repercussions in certain work places where safety checks were vital. ® See also IT equipment is bad for your health Mobile phones are a pain in the neck ...and links to five more brain maim stories