When will there be good news? If your field of interest is the effects of alcohol consumption on your health, you might be forgiven for thinking that there will never be good news. The latest government guidelines have reduced the safe amount that you can consume to zero and recommended that you should limit yourself to no more than 14 units a week or in old money, a pint per day. Given the regular revisions, always in a downward direction I wonder if a glance at a bottle of brown ale will prove lethal in a few years.
However there is a chink of light on the horizon. A study published in the British Journal of Sports Medicine at the end of August this year looked at the protective effects of exercise on the mortality rates of people who consume alcohol and found that there was indeed a measurable effect. In the words of the authors of the paper ‘Stratified analyses showed that the association between alcohol intake and mortality risk was attenuated (all-cause) or nearly nullified (cancer) among individuals who met the PA (Physical Activity) recommendations.’ In other words, exercise can protect you from the increased risk of dying from a number of causes which are thought to be more common in drinkers. For cancer, the increased risk is nullified and for other diseases your chances of contracting them are reduced towards that of non drinkers.
My first reaction was scepticism, given that many of our newspapers seem to divide the world into things that will kill you, or miracle foods which will bestow eternal life on you, so I had a look at the original paper. Unlike some studies, this seems to be sound. A total of 36 370 people is a decent sized sample and the paper was peer reviewed and published in a reputable journal. Clearly there are possible issues – people who exercise are likely to eat more sensibly, subjects may not be totally honest when reporting their alcohol consumption...the list goes on, but it seems that there is a kernel of truth here. Two questions come to mind. First, how much is enough exercise? The answer is quite a lot. In the paper it is expressed in Metabolic Equivalent of Task (MET) units, and the answer is between 7.5 and 15 MET-hour/week. In layman’s terms that adds up to between one and two hours a week of vigorous physical exercise or about 5 hours of walking or cycling. Some exercise machines down the gym have a read out of METs to help you calibrate your exercise regime.
This is the first study to come up with these results, so there is a lot of follow up work to do. Is all exercise equally effective? How frequent should the exercise be? Is a hard session once a week as effective as shorter sessions every other day? Are all patterns of drinking covered, or is binge drinking still risky? Is it possible to reproduce the study or is it just a outlier, which has given a false result? Should we trust the scientists – after all, the former minister for education, Michael Gove said ‘people in this country have had enough of experts’.
However if further supporting evidence is found, maybe the government advisors could modify their message. Ever more dire warnings and cutting recommended limits is never going to work. Perhaps the message could contain a carrot as well as a stick and encourage a healthy exercise regime alongside the dire warnings of overconsumption. Me? I burned 1,000 calories in the gym this morning. See you there.