'Tis the season to prolong your life - go easy on the time-wasting indulgence

Wed, Jan 2, 2013, 00:00

MEDICAL MATTERS:Interested in how the season of eating, drinking and being merry may have affected you? A Cambridge researcher has come up with a statistical method for calculating how our behaviour affects our expected length of life. He says activities like having a couple of drinks and watching television can each knock about 30 minutes off your life for every day you indulge.

So living the 12 days of Christmas at full hedonistic tilt could, according to this theory, be significantly life- shortening.

On a more positive note – and one more in tune with the setting of New Year health resolutions – David Spieghalter, professor for the public understanding of risk at the university, has also calculated that each day of sticking to just one alcoholic drink, eating plenty of fruit and vegetables, and exercising can be expected to add up to two hours to your life.


He has come up with the idea of microlives: a microlife equals a half hour of adult life expectancy as it is loosely equivalent to one millionth of life after age 35, he explains in the Christmas issue of the British Medical Journal (BMJ). Using data from population studies, he calculates that, averaged over a lifetime, a microlife can be “lost” from smoking two cigarettes, being 5 kg overweight, having a second or third alcoholic drink of the day, watching two hours of television, or eating a burger.

On the other hand, microlives can be “gained” by sticking to just one alcoholic drink a day, eating fresh fruit and vegetables, exercising, and taking statins (cholesterol-lowering drugs). And while acknowledging his system’s limitations, Spiegelhalter says “a reasonable idea of the comparative absolute risks associated with chronic exposures can be vividly communicated in terms of the speed at which one is living one’s life”.


However, another recent paper in the BMJ suggests you will not gain much by including a medical “checkup” in your New Year health resolutions. General health checks did not reduce morbidity or mortality, the authors concluded. Nor did they affect either deaths or disability from cardiovascular disease or from cancer.

But health checks did increase the number of new diagnoses for patients, suggesting the possibility they may contribute to harmful outcomes such as overdiagnosis and overtreatment.

The wide-ranging Cochrane systematic review and analysis of some 16 research trials did not find any benefit on subsequent hospitalisation, disability or absence from work.

One trial found that health checks led to a 20 per cent increase in the total number of new diagnoses per participant over six years compared with the control group and an increased number of people with self-reported chronic conditions.

Body maintenance

In an accompanying editorial, Domhnall McAuley, the BMJ’s primary care editor, highlighted some of the unintended effects of check-ups. “A body maintenance programme – like a vehicle service to ensure we are roadworthy – sounds like a good idea. But not every good idea stands up to critical appraisal.

“The most interesting question is whether health checks do harm. People may gain inappropriate reassurance from a verdict of a ‘clean bill of health’, which may lead to continued risky behaviour,” McAuley said. “A false positive test result may cause considerable worry and upset, not to mention inappropriate treatment. A false negative result also provides inappropriate reassurance.

“Policy should be based on evidence of wellbeing, rather than on well-meant good intentions,” he concluded, adding that check-ups for healthy people should not be seen as a good idea purely because “they seem a socially responsible approach to caring for patients”.

So do not waste money on untargeted check-ups. There is no getting away from the well-worn advice of eating plenty of fresh fruit and vegetables, drinking alcohol moderately and regular exercise. But do break out now and again and take the “macro” view.

After all, who wants to “micro” live their lives all of the time?