The studies fail to provide adequate information about what proportion of abstainers were lifelong teetotallers, infrequent drinkers or indeed reformed alcoholics.
Researchers have established that among middle-aged men in the United Kingdom, those who do not drink include a large proportion who have given up drinking because of ill- health or to comply with long- term medication. This may well be the subgroup of the population comprising the downslope of the much fanfared epidemiological J-shaped graph of mortality against alcohol intake.
It is also worth noting that light drinkers are more likely to be higher social class non- smokers who exercise and watch their weight. Not surprising then that these are the same people with lower cardiovascular mortality.
Without fully defining populations and covariabilities there can be no justification for claims that not drinking is harmful or that moderate alcohol intake is protective. To suggest otherwise is fanciful.
Dr Waseem Qasim
Heaton, Newcastle upon Tyne