Comparing the effects of food restriction and overeating on brain reward systems

Abstract

Both caloric restriction and overeating have been shown to affect neural processes associated with reinforcement. Both preclinical and some clinical studies have provided evidence that food restriction may increase reward sensitivity, and while there are mixed findings regarding the effects of overeating on reward sensitivity, there is strong evidence linking this behavior with changes in reward-related brain regions. Evidence of these changes comes in part from findings that show that such eating patterns are associated with increased drug use. The data discussed here regarding the differential effects of various eating patterns on reward systems may be particularly relevant to the aging population, as this population has been shown to exhibit altered reward sensitivity and decreased caloric consumption. Moreover, members of this population appear to be increasingly affected by the current obesity epidemic. Food, like alcohol or drugs, can stimulate its own consumption and produce similar neurochemical changes in the brain. Age-related loss of appetite, decreased eating, and caloric restriction are hypothesized to be associated with changes in the prevalence of substance misuse, abuse, and dependence seen in this cohort.

Maternal nicotine exposure during lactation alters food preference, anxiety-like behavior and the brain dopaminergic reward system in the adult rat offspring

“…Hypodopaminergic signaling could be related with sugar addiction. Sugar shares the characteristics of addiction-inducing substances and its consumption releases both opioids and dopamine [9,10].…”

Dopamine and glucose, obesity, and reward deficiency syndrome

“…We encourage new strategies targeted at improving DA function in the treatment and prevention of obesity a subtype of reward deficiency (Avena et al, 2013a,b). …”

“…These authors Avena et al (2013a,b) classified sugar as addictive, because it follows the typical addiction pathway consisting of binging, withdrawal, craving and cross-sensitization delineated by Blumenthal and Gold (2010) and Blum et al (2011a,b). …”

Prevalence of ‘Food Addiction' as Measured with the Yale Food Addiction Scale 2.0 in a Representative German Sample and Its Association with Sex, Age and Weight Categories

“…In support of the ‘food addiction' theory, animal models provide evidence that highly processed foods (e.g., cheesecake, Oreo cookies) or ingredients added to highly processed foods (e.g., sugar) may be capable of triggering biological (e.g., downregulation of dopamine) and behavioral (e.g., bingeing, use despite negative consequences) processes in a manner similar to drug abuse [16,17,18,19,20,21]. …”