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Food addiction, often characterized by perceived loss of control in the consumption of foods, is much more than just a habitual maladaptive behavior. It involves alterations within the brain-gut-microbiome system, including changes in key brain networks producing patterns of eating behaviors that result in the overconsumption of unhealthy food to an extent that has negative consequences on mental and physical health, overall performance, relationships, and quality of life. At the brain level, distinct neuroplasticity changes develop which drive the repeated execution of maladaptive food intake, such as overriding satiety mechanisms and eating beyond the comfort threshold. The challenge in the treatment of food addiction in comparison to addiction to drugs, alcohol, or gambling, is the fact that food cannot be eliminated as part of the treatment as it is necessary to satisfy the homeostatic needs of the body. In this post, I will discuss foods which have been linked to high rates of food addiction, as well as touch upon the neurobiological mechanisms underlying the addiction to such foods. Finally, I will discuss behavioral tools and dietary suggestions that have been proposed in the treatment of food addiction.

““… distinct neuroplastic changes develop which drive the repeated execution of maladaptive food intake, such as overriding satiety mechanisms and eating beyond the comfort threshold.”

The regular consumption of food is essential to maintain metabolic homeostasis, e.g. keeping an overall balance between homeostatic needs of our body, and energy intake. When homeostasis is achieved, an individual finds itself at a stable, healthy weight, as well as a stable mental emotional state without cravings for more. Food addiction involves a shift in this balance toward constant craving, the over-ingestion of unhealthy foods, often associated with weight gain and other negative health effects. Food addiction is accompanied by an impairment of psychological homeostasis, characterized by a shift of the hedonic setpoint toward a prolonged, primarily negative emotional state. This set point shift is also a characteristic component in drug addiction, where the short lived high induced by drug intake is followed by a prolonged low, an intensely negative emotional state producing more substance seeking and resulting in a long-term shift of the hedonic setpoint. This emotional low becomes the driver of recurring cravings for the substance. Individuals who suffer from food addiction may experience this shift in hedonic setpoint as a withdrawal effect from processed foods that are characteristically high in sugar, fat, and sometimes refined carbohydrates. The addictive effects of high-sugar, high-fat foods are well known to experts in the food industry who have taken advantage of this phenomenon to increase the consumption of unhealthy food items; they have been well described in an extensive literature. The negative emotional state of the withdrawal period may result in the seeking out and overindulging on more of these addictive foods in order to obtain short-term pleasure and comfort. However, when the high subsides, individuals feel worse, overly full, and depressed or ashamed. This negative cycle is often accompanied by perceived loss of control and helplessness, which are some of the key components of addiction. The prolonged override of homeostatic regulation by hedonic motivation may also bring about substantial long-term negative health effects and may be an important contributor to the obesity epidemic.

“…in drug addiction, where the high as a response to drug intake results in a prolonged low, an intensely negative emotional state producing more substance seeking, and resulting in a long-term shift of the hedonic setpoint.”

On a neurobiological level, food addiction is reflected in long-term changes to brain structures and circuits, as well as the release of specific neurotransmitters. Brain areas that have been shown to be altered as a response to prolonged ingestion of high-sugar and high-fat foods include the mesocorticolimbic pathway, subregions of the hypothalamus, the prefrontal cortex, vagal brainstem nuclei and the amygdala, which are all components of central stress circuits. The neurotransmitter dopamine, a central driver of motivation and reward seeking, plays a crucial role in all addictive behaviors. Sensitization of the dopaminergic system in the brain has been directly associated with addiction to foods high in sugar and fat. In a study with rats, intermittent access to sucrose resulted in altered dopamine receptor functioning, a sign of dopamine sensitization. Decreased dopamine levels are associated with withdrawal symptoms from drugs of abuse, and those same symptoms of elevated distress and substance seeking are observed in rats fed a high-sugar diet and subsequent withdrawal. Importantly, in a study investigating the underlying mechanisms of sucrose seeking, a brain circuit involving neurons that release dopamine was identified as the circuit to drive an increase in focus and motivation to seek out sugar.

“Sensitization of the dopaminergic system in the brain has been directly associated with addiction to foods high in sugar and fat.”

Food addiction can produce changes in gut-to-brain signaling through the vagus nerve. Interestingly, rat studies have shown that animals can well develop a strong preference for sugar even if their taste receptors are ablated. This indicates that there exists a mechanism by which sugar hijacks pleasure centers of the brain which operates independent of taste perception in the mouth. A recent paper published in Nature found that sugar preference may be mediated by the activation of a population of nerves in the brain stem and other deep brain structures via the gut-brain axis. These neurons are simulated by the presence of sugar in the gut, and the signal is sent up the vagus nerve to ultimately arrive in pleasure centers of the brain. This gut to brain pathway may be critical in the development of sugar preference and addiction, as it involves an alteration of deep brain structures in response to sugar ingestion. Addiction to high-fat foods has been intensely described elsewhere and involves brain structural and behavioral changes different from, yet just as significant, as those observed in sugar addiction.

“This indicates that there exists a mechanism by which sugar hijacks pleasure centers of the brain which operates independent of taste perception in the mouth.”

Knowing that high-sugar and high-fat foods can hijack the brain’s reward system and produce symptoms of addiction in both preclinical and human studies, it makes sense to eliminate or greatly reduce foods containing refined sugars and/or high content of unhealthy fats, in other words many fast food and comfort food items. The cutting out of ultra-processed foods and reduction of refined sugar and high-fat foods is a critical element in the treatment of food addiction. Furthermore, reducing stress responsiveness through regular practice of contemplative techniques, including mindfulness eating, stress management, fostering healthy relationships, prioritizing daily physical exercise, spending time out in nature, and getting a good night’s sleep are key components in a holistic approach to treating food addiction. Shifting the focus towards ingesting more whole, unprocessed foods with high nutrient density is recommended as a positive approach to breaking any addictions to processed foods. Cooking fresh, healthy meals and enjoying these meals in a low stress environment and a calm mental space are crucial component in recovering from food addiction and setting the stage for healthy enjoyment of food.