Newswise — Risky drinking often co-occurs with maladaptive eating in young adults, according to a study reported in Alcoholism: Clinical and Experimental Research. While previous research had suggested a link between heavy alcohol use and obesity-related factors in college students, the latest study aimed to identify specific profiles of problematic drinking, food addiction, and obesity within a more diverse sample of community-dwelling young people. The researchers also explored shared theoretical risk factors for heavy drinking and overeating, and how these differ across the profiles. Calorie-dense food and alcohol both require little effort to obtain and consume, and each generates immediate and potent experiences of reward in the brain. According to ‘reinforcer pathology’ theory, people who place a high value (‘demand’) on unhealthy items, and who also favor small immediate rewards (such as food and alcohol) over larger delayed rewards (such as health), are at highest risk for overconsumption and poor health outcomes.

The data were from 602 young adults aged 21 to 24 who reported two or more binge-drinking episodes within the past month. All attended a 2-hour testing session, in which they were weighed and measured and provided information on their alcohol use, alcohol problems, and food addiction symptoms. Participants were also assessed for risk factors relevant to reinforcer pathology theory, such as measures of reward functioning and impulsivity.

On average, participants consumed 17 drinks a week in a typical month, with four binge-drinking episodes. Their average BMI was 28, with a quarter classed as overweight (BMI 25-<30) and a third as obese (BMI 30+). Statistical modeling revealed four participant profiles that best fitted the collected data. Most participants (70%) fell into the lowest-risk profile (profile 1), characterized by a moderate severity of alcohol problems (just below the clinical threshold for alcohol use disorder [AUD]) and overweight. Profile 2 (15% of participants) again featured moderate alcohol problems, but also drinking behaviors consistent with AUD, as well as moderate food addiction symptoms and obesity. Profile 3 (7% of participants) was the most severe profile overall, with high severity of alcohol problems (with AUD) and food addiction, and obesity. Profile 4 (also 7% of participants) was characterized by very high alcohol consumption and related problems (with AUD), and overweight, but by milder symptoms of food addiction.

The theoretical risk factors differed across the profiles. Overall, participants in profile 4 (the highest severity profile for alcohol) scored highest for most of the reinforcer pathology measures, including those related to alcohol demand. However, participants in profiles 2 and 3 – who reported both food addiction symptoms and moderate alcohol problems –  scored highest on a ‘reward deprivation’ measure, indicative of lack of access to alternative (healthier) sources of reward, such as recreational activities. Profile 3 participants also scored highly on measures of impulsivity.   

The co-occurrence of risking drinking and food addiction symptoms in this sample is of concern. In future, treatment strategies that address multiple health risk behaviors – for example by targeting the reward and impulsivity factors that seem to confer risk for both maladaptive eating and problem drinking – may help to improve health behaviors and outcomes among young people.

Identifying patterns of alcohol use and obesity-related factors among emerging adults: A behavioral economic analysis. Buscemi, S.F. Acuff, M. Minhas, J. MacKillop, J.G. Murphy (pages xxx).