For the regular boozer it is a source of great comfort: the fat pile of studies that say a daily tipple is better for a longer life than avoiding alcohol completely.

But a new analysis challenges the thinking and blames the rosy message on flawed research that compares drinkers with people who are sick and sober.

Scientists in Canada delved into 107 published studies on people’s drinking habits and how long they lived. In most cases, they found that drinkers were compared with people who abstained or consumed very little alcohol, without taking into account that some had cut down or quit through ill health.

The finding means that amid the abstainers and occasional drinkers are a significant number of sick people, bringing the group’s average health down, and making light to moderate drinkers look better off in comparison.