The links between health, work and wellbeing have been recognized by occupational physicians for hundreds of years but only much more recently by other healthcare professionals, employers and the general public.

There are a number of dimensions to the health–work interface: the health risks of being in and out of work, the health impact of moving between employment and unemployment, and of the effects of work on health, health on work and the role of rehabilitation and of wellbeing.

An independent review of the scientific evidence around health and work by Waddell and Burton (2006) has shown that work:

• can be therapeutic for people with both physical and mental health problems and can help promote recovery
  
• minimizes the risk of the physical, mental and social effects of long term unemployment
  
• reduces social exclusion and poverty
  
• can improve the quality of life and wellbeing

Conversely the review also reported a strong association between worklessness (a term used to describe people who are economically inactive, i.e. of working age but not working, not in full time education or training, and not actively seeking work) and poor physical and mental wellbeing. They also reported that there was strong evidence that unemployment leads to:

• 20% excess mortality
  
• two to three times the risk of poor general health
  
• two to three times the risk of poor mental health
  
• higher medical consultation, medication consumption and hospital admission rates.

The review contained some provisos however—the research which has been undertaken is about group effects—within groups a minority of individuals may experience contrary health effects and that the beneficial effects are dependent on the nature and quality of work undertaken. But overall the authors concluded that work is generally good for health and wellbeing in the majority of cases and that this is true for people with disabilities and for most people with common health problems (such as back pain, stress, anxiety and depression).

It should not be forgotten that work provides more than financial gains—there are also other benefits for specific groups of working age people: for people who are out of work getting back into employment improves their self-esteem and general physical and mental health, and reduces psychological distress and minor psychiatric morbidity.

Exposure to workplace agents, badly designed work and work where there is a mismatch between the individual, their capabilities and the demands of the job (be they physical, psychological or both) can harm health. The Health and Safety Executive annual statistics report that in 2009/2010 approximately 28.5 million days were lost overall from workplace injury and ill health, 23.4 million due to work-related ill health and 5.1 million due to workplace injury. There were also 152 deaths and 1.3 million people reported that in the previous year they believed they had suffered from an illness either caused by or aggravated by their work (HSE 2009/2010).

Despite the large number of people affected and number of days lost due to work which harms health, it is far commoner that lost time results from the effects of health on work, i.e. the person has a health condition which affects their ability to work but which was not caused by their work. Health conditions can result in the person staying at work and working less effectively (sometimes called presenteeism) or lead to their absence from the workplace due to sickness.

Whereas minor illnesses such as colds, flu and headaches are by far the commonest cause of short-term absence, musculoskeletal injuries and back pain are the next commonest for manual workers followed by stress (Chartered Institute of Personnel and Development (CIPD) 2010). Stress remains the second most common cause of short term absence in non-manual workers followed by musculoskeletal injuries and back pain (CIPD 2010). The most common causes of long-term absence are acute medical conditions (e.g. stroke, cancer, heart attacks) followed by musculoskeletal injuries, stress, mental ill health and back pain. Stress and musculoskeletal disorders are particularly common causes of long-term absence in the public sector (CIPD 2010) (Box 2.1).