Influence of moderate alcohol consumption on emotional and physical well-being

Abstract Background and aim: Moderate alcohol consumption has been suggested to contribute to emotional well-being. However, the effects of moderate alcohol consumption on emotional well-being in common drinking situations and the influence of alcohol on physical well-being remain unclear. The aims of this thesis were 1) to further explore the acute effects of moderate alcohol consumption on emotional well-being and the association between habitual alcohol consumption and emotional well-being and 2) to provide more insight into physiological markers that may be related to alcohol-induced emotional well-being. Methods: We compared the acute effects of alcohol (20-30 g) vs. alcohol-free drinks on mood, food reward and mental stress in three randomized crossover trials. To explore the short-term effects of alcohol on physiological markers of emotional well-being, we conducted four randomized crossover trials of 3-6 weeks in which 25-41 g alcohol/day, or no alcohol was consumed. In addition, we conducted a meta-analysis of 14 randomized intervention trials with at least 2 weeks of alcohol intervention. Finally, the association between long-term alcohol consumption and health-related quality of life was investigated with a bidirectional, longitudinal analysis among 92,448 U.S. women of the Nurses’ Health Study II cohort. Results: Moderate alcohol consumption in an unpleasant ambiance resulted in higher happiness scores in women as compared to the consumption of alcohol-free drinks. Consumption of 20 gram alcohol increased subsequent intake and rewarding value of savoury foods in men, as measured by an increased implicit wanting and explicit liking of savoury foods. When alcohol was consumed by male volunteers immediately after a mental stressor, a reduced response of the stress hormones ACTH and cortisol, the inflammatory marker IL-8, and the percentage of monocytes in blood were observed. Furthermore, alcohol consumption was found to attenuate meal-induced NF-κB and to increase total antioxidant capacity in men. Four weeks of moderate alcohol consumption reduced circulating fetuin-A, while increasing urinary F2-isoprostanes in men. In women, short-term moderate alcohol consumption did not reduce fetuin-A but it tended to increase insulin sensitivity. Habitual moderate alcohol consumption was associated with a higher physical health-related quality of life 2 years later. Vice versa, higher physical health-related quality of life was associated with a higher alcohol intake 2 years later. Moderate alcohol consumption was not associated with mental health-related quality of life in either direction, although moderate alcohol consumption was associated with higher scores on the scales for social functioning and vitality. Conclusions: Moderate alcohol consumption may acutely improve emotional well-being by improving mood, increasing food reward and reducing mental stress. In the short-term, moderate alcohol consumption may attenuate meal-induced oxidative stress and circulating fetuin-A in men. In women, moderate alcohol consumption may improve insulin sensitivity. Habitual moderate alcohol consumption may be associated with a small increase in physical health related quality of life but not with mental health related quality of life in women.