Alcohol consumption in a non-clinical sample: The role of sweet-liking, PROP bitterness and sex

Some previous studies have suggested an association between sweet-liking and alcohol use in male alcohol-dependent individuals. However, if sweet-liking is to have value as an indicator of potentially hazardous drinking behaviour, the relationship needs to be established in non-dependent individuals, and determined for women and younger individuals, who may be at increased risk of alcohol use disorders. This study comprised of a non-clinical sample of 223 male and female university students. Responsiveness to 3 sucrose-impregnated taste discs (9 g/l, LSD; 90 g/l, MSD; 900 g/l, HSD) and a 50 mM 6-n-propyl-2-thiouracil (PROP)-impregnated disc were collected and used to classify participants as sweet-likers (HSD/LSD ≥ 1.5), sweet-dislikers (HSD/LSD < 1.5), PROP non-tasters (gLMS intensity score ≤ 12 mm), PROP medium-tasters (13-55 mm), or PROP supertasters (≥ 56 mm). Data on familial history of alcoholism, alcohol intake, and hazardous drinking (Alcohol Use Disorders Identification Test, AUDIT) were also collected. Two-way Analysis of Variance showed a significant main effect for sweet-liking on alcohol consumption in males (F (1)=4.10, p=0.04), with monthly intake (natural log transformed) of sweet-liking males higher than sweet-disliking males. Neither alcohol consumption (t (191)=1.97, p=0.23), sweet-liking (ratio of HSD liking over LSD; t (191)=1.97, p=0.41), or PROP responsiveness (t(191)=1.97, p=0.56) varied with AUDIT classification or family history of alcoholism (p> 0.05). Overall, our results partially support the hypothesis that ethanol and sucrose influence the opioid reward system in the brain in a similar way to reinforce use.