Scientists must recognize that eating disorders, food addiction, and food withdrawal are very similar to drug withdrawal states especially in terms of concomitant over-eating and even weight gain by the addict. This concept was first considered by Blum’s group in the 1970s and later refined by Gold’s group in the early 1980s. It is well recognized that early abstinence is characterized by a rebound hyperphagia—overeating and weight gain during abstinence from drug abuse. While cigarette smoking cessation is often associated with hyperphagia and continued weight gain (possibly due also to alteration in liposome enzyme activity), there is genetic evidence for why people may gain weight from food. This effect was highlighted by a study showing that weight gain in subjects that carry the dopamine D2 receptor gene variant continues for more than a 1-year period due to a blunted brain reward response. In simpler terms the reward part of the brain cannot perceive the effect of food and as such is never satisfied.
Substance abuse and eating are related for many reasons, not the least of which is that drugs hijack the brain by co-opting existing primary brain reinforcement systems. Understanding the role of tolerance related to excessive DA release in the NAC was indeed a reality observed by the Woodstock generation with a mantra of “sex, drugs, and rock and roll,” whereby too much of a good thing resulted in the loss of its reinforcement. Today we see it, for example, in sex addiction self-help programs.
It is extremely important to realize that even today, many of the 14,500 treatment centers, including 12-step programs, serve cakes, cookies, and coffee as an adjunct to help during recovery. Certainly, addicts looking for advice on staying sober are told at AA meetings never to get too hungry and to carry around sugar or candy for “drug” cravings. My scientific and clinical associates encourage medical assisted FDA approved drugs during short-term treatment; however, we need more healthy diets designed by experienced chefs serving up more “dopamine for dinner” such as the recipes provided in Joan Borsten’s Malibu Beach Recovery Diet Cookbook (2015) a cookbook designed specifically to help addicts and alcoholics in recovery.
Kelly Brownell and Mark S. Gold summarized the field in their book Food and Addiction (2014). Their pioneering efforts resulted in a book that adequately provides the basis for food as a truly addictive substance just like cocaine and other psychoactive licit and illicit substances of abuse. Bulimia, anorexia nervosa, bingeing, and hyperphagia as repetitive behaviors share the neurochemical and neurogenetic mechanisms and all meet the criteria of addiction as espoused by ASAM.
The director of NIDA Nora D. Volkow recently pointed out that research into addiction prevention and treatment would benefit from patient classification into reproducible categories that have predictive validity and require the development of better biomarkers. Undoubtedly urine drug testing (e.g., CARD™ by Dominion Diagnostics) is a clinically valuable biomarker for relatively recent drug use. However, to determine both chronic use and potential high risk Volkow suggests that more research is required to investigate epitranscriptomics, genetics, epigenetics, and human brain function and neurochemistry. By doing so, this will enhance our ability to screen and treat patients with substance use disorders, including food addiction, possibly via common treatments (e.g., dopamine agonistic therapy).
In terms of novel therapies, my group recently reviewed the possibility of vaccines and even gene therapy and suggested that the field of addiction medicine due to its complexities and polygenic inheritable factors will not see benefit from these enormous scientific advancements for many years. Although it is unlikely that we could attack glucose craving through either a vaccination or gene therapy, we may be able to develop better animal models for anorexia nervosa and bulimia in the future to help us formulate new treatments.