I just heard an interesting broadcast on the Beeb – radio 4 Inside Science, 29th January 2016 – about safe alcohol levels. Which set out saying government advice is it’s best not to drink at all, or if we must, only drink a little bit each day – less than 1 small glass of wine. And then it got interesting: how is this advice arrived at? By studies done on the effects of alcohol: which led to the difficulties of studying alcohol consumption.
Comparisons with non-drinkers.
Whilst some people don’t like drinking and never have, some non-drinkers are ex alcoholics or people who have had difficulties keeping their alcohol intake under control; some of them are deeply religious, which is not the norm in the UK; or the people are exceedingly poor, so can’t afford drink. What the programme was saying is that people who don’t drink in the UK are in the minority and the reasons for people not drinking give them all different health outcomes – good or bad, which makes drawing any health conclusions from non-drinkers as a group difficult.
Lying.
Hah. The way they study alcohol consumption is by asking us how much we drink. And how much we, as a nation, say we drink, does not tally with sales of alcohol. Nope. We lie or underestimate how much we are drinking – and it isn’t just us Brits who confidently confess to one glass of wine a night, whereas the truth is nearer two glasses. Apparently other countries fib about their consumption too – what the nation says it drinks does not equate to what the nation buys. So if drawing conclusions about safe levels of drinking based on the health of moderate drinkers – how do we know how much they are really drinking? Are the people with good heart disease predictions, who claim to drink one small glass of wine a day, really drinking two glasses? We just can’t tell.
The need for clear health warnings
The beneficial effects of alcohol are the most scrutinised with the aim of ending up with a clear health warning that alcohol is bad for you and we are better off going tee total.
At which point we were introduced to Professor David Spiegelhalter, Cambridge University Maths department. I’m so glad I didn’t know he was head of Maths or I would have immediately panicked and assumed I would understand nothing. Amongst other studies, Prof Spiegelhalter studies studies and how they are interpreted – or misinterpreted by Media and politicians. So if we drink too much we run a 1/100 chance of developing a related disease, for example breast cancer or liver disease. Measure this against smoking: we run a 50/100 risk of developing a related disease. Apparently sedentary behaviour has a worse health outcome than moderate overdrinking – unfortunately the programme cut off before I could get the figures. Which means of all the bad behaviours we like to indulge in, slobbing about on the sofa sucking on a fag is much worse for you than having a couple of glasses of wine a night.
In its drive to have us cut back on the booze, government commissions studies on alcohol, and the media can pick up on some part of a newly published study and blow it out of all proportion. Prof Spiegelhalter wrote a paper detailing what happened to two academic papers published in October and November 2007. The alcohol related paper was drawn from the NWPHO (North West Public Health Observatory) ((The nattily named NWPHO is based at Liverpool John Moores University and core funded by the Department of Health)) data base, using the search terms Alcohol and Middle-class and it was a report on drinking habits in England. The initial report
received almost no print media attention in the first instance. On 15 October it published, online, a list of drink indicators based on the figures of the report, but this time arranged by local authority. These indicators included alcohol-attibutable hospital admission rates, alcohol-related crime rates as well as hazardous and harmful drinking……. For the last two indicators there were no direct figures for the local authorities and therefore the figures in the league table are synthetic [or predictive] estimates. In particular, one of the tables showed well-off middle-class areas such as Runnymede in Surrey and Harrogate in Yorkshire to come out on top as having the highest percentage of people indulging in hazardous style drinking behaviour, while relatively deprived urban areas such as Tower Hamlets and Hackney were at the bottom of the league table. It was this follow up report that received media attention, even getting onto the front page of some newspapers. ((Spiegelhalter D, Riesch H. Careless pork costs lives: risk stories from sicence to press release to media, Health, Risk & Society, 13:1, 47-64, DOI 10.1080/13698575.2010.54645))
Essentially this means that a load of figures and tables were produced from the search terms alcohol and middle-class, only the sample sizes weren’t always large enough, so from what they had, they made the numbers up. Since one of the search terms was middle class, not surprisingly middle class areas such as Runnymede and Harrogate scored much worse than the poorer boroughs of Hackney and Tower Hamlets. And the press made a big fuss over the last part of the report, ignoring the rest of it, coming up with such headlines as:
‘Our green and drunken land.’ Brown J, 2007 Independent 17th October.
‘My ‘just one drink’ always leads to two or more.’ Gordon B, 2007. Daily Telegraph, 17 October.
‘It’s our poison…..so leave us alone.’ Wostear, S, 2007. The Sun, 17 October.
‘Vice rife among Runnymede’s middle class’ Shilling, J, 2007. The Times, 17 October.
A couple of definitions: hazardous drinking means drinking between 22 – 50 units a week for men or 15 – 35 units a week for women. Harmful drinking is above this level. A bottle of wine at 12° contains 9.4 units, a bottle at 14.5° contains 10.75 units.
Following current advice, both men and women should drink below 15 units a week to be safe. Incidentally, these magical numbers were arrived at by the Royal College of Physicians in 1987.
These figures are questionable, given the difficulties of studying alcohol. They may also be meaningless since as individuals some can handle alcohol better than others: not everybody who drinks goes on to become a hopeless alcoholic, after all.
To add more confusion to the mix: when we drink alcohol, we produce Aldehyde dehydrogenase in our liver to detoxify us. The Japanese are renown for not having the gene to produce this stuff ((Goedde HW, Agarwal DP. Aldehyde dehydrogenase polymorphism: molecular basis and pheotypic relationship to alcohol sensitivity. Alcohol and alcoholism, Oxford, Oxfordshire.Supplement. 1987: 1.47-54. Abstract)). We also need to produce alcohol dehydrogenase, and there are national genetic variants on our ability to produce this. The link will take you to a summary. This means that we have individual ability to break alcohol down. Add to this our height, build, the amount of fat we are carrying and the amount of muscle mass – this is why for a long time the ‘safe’ levels of alcohol were less for women than for men.
It is all very confusing, which leads me to the prevention paradox. In order to improve the health of the nation overall, the government aims to change the behaviours of the reasonably healthy majority a bit, rather than make the very unhealthy minority make large changes. But this does not necessarily mean that on an individual basis, following government advice and going from a low risk life style to an even lower risk life style will make a blind bit of difference. ((Rose, G. 1992. The strategy of preventive medicine. Oxford:Oxford Scientific Publications. Abstract.))
There are up sides to drinking alcohol: it improves blood flow, a small amount is relaxing and can be very enjoyable. There are down sides to drinking alcohol: the risk for various cancers like liver, breast and colon cancer rise along with developing liver disease. If we do drink alcohol, we need to drink it regularly so we keep producing the dehydrogenases. Dry January is all well and good, but we undo all the good we did if 1st Feb ends in an alcoholic haze, since we have lost our ability to detoxify the alcohol and our liver gets an almighty pounding. Alcohol: friend or foe? Well, it’s clearly both.
