Parliament’s recent report encouraging Britons to have two drink-free days per week attracted much attention. This advice was coupled with the seemingly less controversial recommendation that the current daily alcohol limits – 3 to 4 units for men and 2 to 3 units for women – not be increased.
The reasoning for this is that many people are already overindulging. According to Alcohol Research UK, more than 10 million adults in the UK, or about one-fifth of the adult population, are drinking over the daily limit. The charity also says that alcohol-related deaths in the UK are on the rise.
But, not everyone who contributed to the recent inquiry by the House of Commons’ Science and Technology Committee agrees with this reasoning. Dr Richard Harding, a member of the 1995 working group that set the current drinking guidelines, believes that research since then has strengthened the health case for alcohol – and that by trying to solve a societal drinking problem, the Government’s advice may be limiting our individual health benefits.
Science under development
Take the “cardio-protective” effect – the finding that drinking small amounts of alcohol daily can decrease one’s risk of coronary heart disease. In 1995 the effect had been documented, but there was disagreement over the appropriate control group. If unwell people chose to quit drinking, and were therefore lumped into the “non-drinkers” category, the comparative health of the “drinkers” group would be a false signal. This concern is known as the “sick-quitter hypothesis”.
Since 1995, however, improved methods have allowed researchers to remove sick-quitters from analysis, and the cardio-protective effect has still been documented. One powerful recent study, published in the British Medical Journal, concluded that consumption levels up to 15g/day (nearly 2 UK units) were associated with about 25 per cent reduction in risk of death from cardiovascular disease.
Cancer risk has been another area that has seen important research in recent years. The Million Women Study, carried out from 1996 to 2001, found that women who drank moderate amounts showed an increased risk of breast cancer and cancers of the oral cavity, the oesophagus and the larynx – all of which had been previously been found in studies of men who drank. What was more surprising was that moderate-drinking women showed a decreased risk of non-Hodgkin lymphoma, thyroid cancer and renal carcinoma.
Balancing the risks and benefits is challenging, and at its heart is why experts disagree on drinking guidelines. Dr Harding, however, told the committee that in his estimation the health reward is often greater than the risk: “There is a risk, but on balance the data show that if they wish to consume alcohol for health reasons the net effect is beneficial.”
The problem of guidelines
Alcohol guidelines exist primarily to inform, not to change behaviour, the Science and Technology Committee heard from a number of experts in two days of verbal testimony. Dr Harding, however, asserts that a large proportion of the UK population is not being informed, for the sake of changing behaviour of a few.
In his supplementary evidence given to the committee, Dr Harding writes that the 1995 report acknowledged the cardio-protective effect but advised against raising the “sensible limits” because “there would be an adverse effect on public health”. Similar advice guided Parliament’s 2011 report.
“The problem with this,” Dr Harding writes, “is that public health messages on alcohol are addressed to populations, but received by individuals, and those individuals are encouraged to believe that following this advice will benefit their health. But this is not necessarily the case if the purpose of the advice is to peg individual consumption to a particular population mean so that other people, towards the end of the graph, are less likely to misuse alcohol. It seems to me that this is manipulative, and in my view any advisory level of intake justified on this basis is politically indefensible.”
This effect may be most prominent in women, since UK guidelines advise them to drink less. A prospective study published in 1997 found that drinking 1.5 to 29.9 g per day was associated with a decreased risk of death from cardiovascular causes. That translates to up to 3.7 units per day that could be beneficial for women, but in the UK they are advised to drink only 2 to 3.
What’s more, the effectiveness of using such a blunt tool to reach problem drinkers is likely to be small. According to Dr Mark Prunty, adviser for the Department of Health, 44 per cent of those drinking above guidelines think that the risk claims are exaggerated. And even if they believe the risks, only about 15 per cent of high risk drinkers want to change their behaviour, he said.
Cardio controversy
The extent of the cardio-protective effect is, however, contested, says Nick Heather, professor at Northumbria University and trustee of Alcohol Research UK. “It is a very controversial area. Even among experts there are sharp differences of opinion on what’s called the cardio-protective effect. Some people deny that the cardio-protective effect exists at all. This kind of thing frequently happens in science.”
In addition, research since 1995 has qualified the cardiac benefits. A 2004 review found that the cardio-protective effect appears to be greater for men than women, and greater for the elderly than the young. It suggests that wine may exert more protection than beer.
The Government’s official drinking guidance has yet to change to incorporate the two drink-free days recommended by the committee’s report, though it was recommended that the Department of Health set up a working group to re-examine the guidelines. In the meantime, one course of action for those interested in how much they should be drinking is to settle in front of the computer, pour a glass of wine, and dig into the ongoing scientific debate.
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