Abstract Increases in Opioid Use Disorder (OUD) in the last decade has created a public health crisis. Methadone maintenance treatment (MMT) is the most common treatment for OUD. While MMT is effective in helping patients improve their quality of life, physical and mental health comorbidities are common and increase risk for premature death. While unhealthy lifestyle behaviors such as physical inactivity and cigarette smoking have been targeted, the role of nutritional intake in this population has been relatively unexplored. Clinically significant increases in weight (at least 10%) have been consistently observed, as well as oft-reported cravings for sweet foods upon MMT initiation. Missing from the existing literature is a clear understanding of why this phenomenon occurs, limiting the ability to effectively target this problem with appropriate intervention. Purported explanations for weight gain have included increased food intake to compensate for undernourishment during the time of active illicit opioid use and the pharmacological effects of methadone on pancreatic cell dysfunction and sweet taste preference. However, these possibilities may only partially explain weight gain as most patients starting treatment are already overweight or obese and increases in weight continue even when methadone doses are stable. We are proposing an additional hypothesis: patients starting MMT will consume foods that are highly palatable (HPF; i.e., high in fat, sugar, or both) in an effort to manage negative affect and opioid cravings that are common during early recovery. Anecdotal reports of patients in substance use treatment provide support for this hypothesis – HPF provide emotional relief and decrease drug cravings. An emerging body of basic science literature demonstrates shared neural mechanisms of both HPF and drugs of abuse. As with drugs, HPF potentiates endogenous opioid and dopamine release in the nucleus accumbens, which, through repeated overconsumption, can also lead to disrupted reward pathways. Indeed, in non-substance using populations, overconsumption of HPF can lead to poorer psychological functioning such as depression and anxiety (known relapse risks in those with OUD). Therefore, while HPF may have a short-term beneficial effect on improving negative affect and decreasing opioid cravings among patients in MMT, it may also confer a longer-term risk for relapse in this population. Understanding the within-person associations between negative affect, opioid cravings, and consumption of HPF at the daily level and over the course of early MMT initiation is critical for informing the development of adjunctive, nutrition-focused interventions in this at-risk population. We propose to conduct a 26-week prospective study of 80 patients who recently initiated MMT utilizing ecological momentary assessment (EMA; through three, 21-day bouts). In doing so, we can answer the question of whether HPF consumption during early MMT is beneficial or detrimental to risk for returning to illicit opioid use. With this information, more effective interventions could be developed to extend recovery and decrease the public health impact of OUD.

Public Health Narrative Opioid Use Disorder (OUD) continues to be a significant and costly public health concern. Research on factors that may contribute to treatment outcomes and the chronic health risks of individuals receiving methadone maintenance treatment (MMT) for OUD is critically important. One area of research that has received relatively less attention in this population is the role of nutrition and dietary intake in relation to relapse and treatment outcomes. Of particular relevance to persons on MMT is the consumption of highly palatable foods (HPF; i.e., foods high in fat and/or sugar) to manage opioid cravings and negative affect in early recovery. However, overconsumption of HPF is also associated with dysfunctional brain reward pathways and negative emotional states. Therefore, it is not clear whether HPF consumption to manage affect and cravings when starting MMT would be beneficial or lead to higher risk for relapse. Systematic study of the daily associations between opioid cravings and HPF consumption is necessary to help inform potential nutrition- focused interventions that could improve outcomes in this at-risk population.