Effect of dietary stimulation on acute changes in GLP-1, alcohol responses, craving, and attentional bias: a randomized, placebo-controlled laboratory study.

RATIONALE: Preclinical and clinical findings support the potential for GLP-1 receptor activation to reduce alcohol consumption and reward. Human experimental studies are needed to clarify whether acute changes in endogenous GLP-1 influence alcohol craving and responses to alcohol. Dietary stimulation may present a method to study the effects of endogenous GLP-1 on responses to alcohol.

OBJECTIVES

Assess the effects of a dietary manipulation on acute changes in GLP-1 and laboratory responses to alcohol.

METHODS

Healthy young adult heavy drinkers (N = 40) were recruited to participate in two study visits where they received a dietary supplement designed to increase endogenous GLP-1 or a calorically matched placebo in counterbalanced order. Blood was sampled before and 40 min after supplement or placebo administration to measure changes in plasma GLP-1. Subjective effects, craving, and alcohol attentional bias were measured in response to a priming drink of alcohol (target BAC 30 mg%).

RESULTS

Compared to placebo, dietary supplement preload significantly increased blood GLP-1 concentration, β = 0.79, p < 0.001, and significantly reduced alcohol attentional bias, β = -0.56, p = 0.010. Blood GLP-1 concentration correlated with the magnitude of alcohol attentional bias reduction after supplement preload (r = -0.30). There were no significant effects of the manipulation on subjective responses or craving.

CONCLUSIONS

Results suggest that dietary stimulation may reduce the incentive motivational properties of alcohol-related cues, potentially through increases in endogenous GLP-1, absent effects on self-report measures of alcohol subjective response or craving. Acute changes in circulating GLP-1 may influence implicit motivation for alcohol.