Imagine a medical check-up that dispensed with examinations and investigations as well as questionnaires about smoking or exercise or the state of your mental health. Envisage the possibility that all the doctor might need to assess your health and predict problems was your job description - and perhaps your postcode, should a second opinion be required.
It won't ever happen, of course. But a new book launched today reveals that the key factor influencing your physical and mental health is neither your genes nor your behaviour - whether you smoke and drink, take exercise or eat fatty foods. These factors together account for less than four out of 10 premature deaths. What really ensures good health and survival hasn't changed since Babylonian times: the efficiency of our "fight or flight" response, the way our hormones rise and fall in response to perceived physical threat. A wealth of new research shows what determines this is the amount of control you have over your everyday life.
At the core of The Social Determinants of Health - co-authored by professors Michael Marmot and Richard Wilkinson with members of the International Centre for Health and Society at University College London - is the ground-breaking Whitehall Study, which followed over 17,000 civil servants for 30 years. Published in 1996, it found that wealth and status are the crucial factors in health and longevity - far more important than racial or educational inequality or even smoking.
In a nutshell, the more seniority you have at work, the less likely you are to die prematurely. Compared to a Sir Humphrey-style mandarin at the top of the civil service tree, the study found, a clerk on the lowest rung is four times more likely to die prematurely. And the relationship between social status and good health holds right at the top of society, where an abundance of good fortune might seem as though it should even things out.
A second study, Whitehall II, launched in 1985, delved further and found that you don't have to be hugely rich and important to enjoy optimum health, although it helps. It's the power to control all aspects of your life - work particularly - that wealth and status tend to confer that is the key determinant of health. Men who have low job control face a 50% higher risk of new illness: heart attacks, stroke, diabetes or merely ordinary infections. Women are at slightly lower risk but low job control was still a factor in whether they fell ill or not.
"Is it plausible that one's sense of control over life could affect the likelihood of developing and dying from chronic diseases such as diabetes and heart disease?" asks Professor Michael Marmot, who launches his book today at the Faculty of Public Health Medicine's annual scientific meeting in Glasgow. "The answer is an emphatic yes."
The biology of social inequality, as scientists are calling the phenomenon, is rooted in the fight or flight response, which we evolved to cope with stress. Faced with an event or some other catalyst that threatens normal functioning, the brain sends signals to the adrenal glands making them pump stress hormones - first adrenaline, then cortisol - into the bloodstream to create the energy and focus to deal with a short term crisis.
For the Sir Humphrys of the world of work, in a position to make decisions and exert authority, dealing with stress becomes invigorating and health promoting. But lower down the chain of command, relentless demands and challenges may activate the fight or flight response too hard and too often.
"As humans we are exquisitely sensitive to our position in the hierarchy, to put-downs, being excluded, or not being valued," says Wilkinson. "Simply being at the bottom of the heap causes an acute state of anxiety - which explains why the adrenal glands of paupers are larger than those of the middle classes."
A stress response provoked too frequently may permanently divert the body's resources away from tissue management and repair, digestion and growth - lowering immunity and elevating blood pressure. High levels of circulating adrenaline are known to increase the stickiness of blood platelets and raise the output of fibrinogen from the liver. Recent research has linked this to cardiovascular disease, cancer, infection and cognitive decline (accelerated ageing). The US government has prioritised research into health and social class above race, education and access to health care.
In Britain, the Health Education Authority (HEA) is to launch a People at Work campaign at the end of this month. A new leaflet identifies lack of control over work as a major stressor. It also encourages people to stand up against bullying, form alliances with colleagues, join trade unions and get involved in schemes that promote staff participation.
"Poverty doesn't necessarily mean bad health," says Professor Pamela Gillies, HEA director of research. "What seems to make the difference is outward-looking, social networks that help people feel in control. Health education needs to have a wider context."
The Social Determinants of Health is published by OUP in August, price £26.50. To order People at Work phone the HEA on 0171 413 1991.