More than half of British managers admit to being unproductive for at least a fifth of their working time because of poor health, new research has suggested.
The study by the Chartered Management Institute and small business health service Workplace Health Connect has found sickness levels are increasing, yet managers are unwilling to report their symptoms.
Nearly four out of 10 of the 1,541 managers polled said they had difficulty concentrating because of ill-health, it found.
Organisations are also not doing enough to tackle workplace illness, which in turn has a negative impact on well-being and performance.
Six out of 10 of those polled claimed illness rates in their organisation have increased over the past 12 months.
But just one in three reported symptoms to their line manager, indicating a much deeper malaise, argued the CMI.
More promising, however, was the finding that 61 per cent of managers felt the senior management team in their organisation considered health and safety to be important.
Almost half suggested that the issues were becoming increasingly important. This figure rose to 52 per cent for growing companies but was notably reduced among declining firms (36 per cent).
Nearly all organisations had general health and safety policies in place, yet far fewer (57 per cent) had policies on occupational illness or managing absence (68 per cent).
Fewer still offered training in these two areas (28 and 35 per cent, respectively).
Where health initiatives and benefits were offered by organisations there was an increase in the physical and psychological health of employees, said the CMI.
While flexible working patterns had become relatively common, health screenings or stress management advice was less common.
Mary Chapman, CMI chief executive, said: "The health of UK workplaces needs greater attention.
"With such high levels of illness being experienced, organisations and individuals must act to maintain their competitive edge.
"Failure to do so will lead to disruption because health clearly has an impact on performance, productivity and ultimately, the bottom line," she added.
Elizabeth Gyngell, programme director at Workplace Health Connect, said workplace ill-health was having an adverse affect on the UK's productivity.
"Everyone needs to play a role in improving the quality of health in their workplace. By working together, the right systems and procedures can be put in place that should benefit the entire workforce and the business itself," she added.