- People who binge eat are not all the same, and individual treatment needs vary.
- Identifying the subtype using neurobiology, characteristics, or diagnosis could inform treatment choice.
- Subtyping could point clinicians towards the best medication choice and/or food plan for the individual.
People develop problems with binge eating and food obsession for a variety of reasons. Clinical trials show a wide variability of clinical response to pharmacotherapeutic, behavioral, and/or nutritional interventions: some people have a complete recovery, while others experience little to no improvement. One size does not fit all.
Acknowledging the heterogeneity could improve our ability to treat people. This push to identify subtypes is in line with widespread efforts to utilize more “precision medicine” across all fields of medicine and behavioral health including depression and substance use disorders (parts 1-4 of this series).
Is Food Addiction Present?
Whether or not food addiction (FA) is a valid or helpful concept is still quite controversial in the psychiatric and psychological communities. FA is not an official diagnosis in the DSM-V, although it was considered by the committee, during its writing, in part because there is growing evidence that some food (for example, high-sugar and some highly processed food) operates on the same neurobiological pathways as drugs of abuse
According to one validated scale—the Yale Food Addiction Scale, derived from the DSM-V criteria for substance use disorder—some (but certainly not all) people with obesity or binge eating disorder may also have FA. Whether or not someone meets the criteria for FA could help clinicians develop more effective treatment plans and individualize treatment for people looking to restore balance in their eating.
Whether or not FA can be used as a matching variable is theoretical, as FA is still not a formal diagnosis. That said, the possibility that addiction-like mechanisms may be contributing to their problems can be assessed by a trained clinician (ideally someone familiar with eating disorders and food addiction treatment) and the YFAS and could inform recommendations when on the fence.
It's possible that FA may be more responsive to addiction-like models of care. For example, people who meet the criteria for so-called food addiction appear to be more susceptible to the rewarding and conditioning effects of high-sugar, highly-processed foods. As people with substance use disorders often find they need to “quit” a drug to find relief, removing or significantly reducing the intake of certain foods (often sweet or ultra-processed) can be the ticket that catapults someone into recovery.
However, people with a clinical history of frequent or intense restrictive eating—excess dieting, body image distortions, and starvation—could theoretically be made worse by a recommendation to restrain from consuming certain foods. So, abstinence-based food plans should be applied with some caution, and in collaboration with a trained provider.
Many of our addiction treatment medications (parts 2-4) are also used for binge eating disorder and weight loss (e.g. naltrexone, bupropion, topiramate, long-acting stimulants). They could be working for both sets of disorders by normalizing function in brain circuits that mediate addiction and theoretically could work especially well for those who meet the criteria for comorbid FA, if the diagnosis is further established.
Would people with so-called food addiction also be more likely to respond to motivational interviewing given how well it works in individuals with substance use disorder? This, too, is unknown, but also deserves study.
What we also know is that people who have FA, at least according to the YFAS, don't as well to more classic approaches to weight loss and eating disorder treatment, and may need alternate treatment plans (such as medications that work on addiction brain circuits or abstinence-based approaches as mentioned above). In one study, for example, researchers found that people who met the criteria for FA had less favorable weight loss outcomes post-sleeve gastrectomy compared to those without. In another, those with higher FA severity at baseline were less likely to obtain abstinence from binge-purge episodes following standard eating disorder treatment than those with lower severity.
Other Approaches to Subtyping
An intriguing recent study identified three subtypes of people within a group of individuals who met the criteria for FA and suggested that these could be used to match these individuals to treatment. Three clusters were identified: a group characterized by the highest ED severity and psychopathology, for which authors proposed treatment focused on ED symptomatology; a cluster with the highest levels of FA for which authors proposed treatment could target FA aggressively, focusing on reward-related processes and conditioning, and encouraging removal of trigger foods; and a group with a high prevalence of obesity but more grazing behavior than bingeing for whom authors suggested that focusing on reduction in weight and calory intake first, and/or bariatric surgery.
Other researchers are exploring whether parsing binge eaters based on neurocognitive profiles—similar to what is being done in substance use disorders, by the predominance of negative emotionality (aka emotional eating, or relief motivation), impaired executive control (impulsivity), or heightened incentive salience (aka external eating, or reward motivation). Weight loss leads to reduced external eating over time (perhaps due to the fact that there is less reward-based conditioning), but emotional eating did not remit, which would imply that people with emotional eating should engage in some deeper therapy work. Both external and emotional eaters might benefit from medications or interventions (exercise, for example) that reduce impulsivity, authors of one study concluded.
The obesity field is emphasizing that “pharmacologic therapy [should be] directed toward the predominant phenotype observed” (Zandvakili et al.) even more than the addiction field. In one recent landmark study, this kind of “phenotype-guided approach,” matching treatments to subtypes, was associated with a 1.75 greater weight loss than standard treatment.
The guided approach used one of four pre-defined obesity subtypes—abnormal energy expenditure (“slow metabolizers”), abnormal emotional eating behaviors (“emotional hunger”), abnormal satiation (“hungry brain”), and abnormal satiety (“hungry gut”) to match the person to pharmacotherapy based on their subtype [phentermine, bupropion-naltrexone, topiramate-phentermine, GLP-1 receptor agonists (of which the now famous Ozempic is one), respectively.
A potentially useful approach which hasn’t yet been well studied either, but which makes theoretical sense, could be to subtype and treatment match based on the presence or absence of co-morbidities.
Someone with comorbid major depressive or anxiety disorder, for example, could be prescribed a selective serotonin reuptake inhibitor, which is indicated for binge eating disorder and mental health diagnoses. Someone with both binge eating and alcohol use disorder might be best served by topiramate, which is known to promote weight loss, reduce binge eating, and reduce alcohol consumption.
For someone with ADHD, we might lean to prescribe lisdexamfetamine or bupropion, which are also known to reduce binge eating and improve attention. If they have type II diabetes, a GLP-1 agonist may be the ticket as it treats diabetes and promotes weight loss. If someone with treatment-resistant major depressive disorder, rTMS treatment is indicated, which may also reduce compulsive eating by improving impulse control, studies show.
Although there is much yet to be researched, we can probably safely start using targeted treatment of binge eating and food obsession, to some degree, today, choosing medications and making dietary recommendations based on some of the subtypes mentioned above.
Wilcox, C. E. (2021). Food addiction, obesity, and disorders of overeating: An evidence-based assessment and clinical guide. Springer Nature Switzerland AG. https://doi.org/10.1007/978-3-030-83078-6