My name is Eilidh Selfridge, and I am currently a fourth-year undergraduate medical student at the University of Dundee. In the previous academic year, I completed an intercalated BMSc in Forensic and Legal Medicine under the supervision of Dr Helen Brownlow of the Centre for Forensic and Legal Medicine.
Alcohol places a large burden on our health services but without being able to accurately quantify intake, it is difficult for the public to drink at a safe level. My research project aimed to assess the ability of the general public to accurately free-pour a given volume of alcohol and therefore accurately estimate their alcohol intake.
Alcohol consumption in the home: Do we really know how much we are drinking?
Introduction: Safe alcohol consumption requires drinkers to accurately track their intake against a recommended limit. Since the majority of alcohol sales are for home consumption, a trend exacerbated by the COVID-19 pandemic, there is concern that the lack of pour accuracy and standardised serving volumes in the home is leading to underestimation of alcohol intake.
Aim: To assess public ability to free-pour a 1-unit spirit serving of 25ml.
Method: Participants (n=44) were asked to pour 25ml into 7 differently shaped drinking glasses and complete a pre- and post-activity questionnaire on their drinking habits.
Results: The overall average volume poured was 37ml (range 8-90ml), 48% in excess of the target. Glass shape, participant age, sex, weekly alcohol intake, prior bar training and alcohol-related health education did not aid pour accuracy. After being informed of their poured volumes, 71% of participants agreed that their previously estimated alcohol intake was likely to be inaccurate.
Conclusions: Over-pouring by a group knowledgeable of standard unit size suggests that that knowledge and experience alone is insufficient to overcome the technical challenge of accurately free pouring 25ml and that education of serving sizes and recommended weekly limits alone is insufficient to tackle excess alcohol consumption. The over-pouring of spirit servings by 48% means that individuals with a weekly alcohol consumption of around 10 units are, in reality, consuming in excess of the recommended maximum of 14 units.