Little has been known about the consequences of long-term, binge-like sugar consumption on the brain. As sugar can cause the release of dopamine in the nucleus accumbens (NAc) similarly to drugs of abuse, scientists from Australia’s Queensland University of Technology investigated changes in the morphology of neurons in this brain region following short- (4 weeks) and long-term (12 weeks) binge-like sucrose consumption by rats.
With reports estimating that up to 75% of all foods and beverages contain high amounts of added sugars, there is concern about its impact on neurological adaptations in brain. Long term binge-intake of sugar, altered neurons within the nucleus accumbens region of the brain, reducing their length, specifically, in the shell of the NAc.
The nucleus accumbens plays a central role in the brain’s reward circuit. Its operation is based on two neurotransmitters – dopamine, which promotes desire, and serotonin, whose effects include satiety and inhibition.
The results from their study they report, add merit to the hypothesis that sugars such as sucrose potentially have addictive properties following long-term, binge-like consumption. Our results also have implications for the growing number of children and adolescents who maintain unhealthy eating habits (high sugar consumption and binge eating) into adulthood. In line with the increased risk of developing metabolic effects it is also possible that neurological and psychiatric consequences affecting mood and motivation may also result from these behaviors.
“Excess sugar consumption has been shown to repeatedly elevate dopamine levels which control the brain’s reward and pleasure centers in a way that is similar to many drugs of abuse including tobacco, cocaine and morphine.” said Professor Selena Bartlett.
“After long-term consumption, this leads to the opposite, a reduction in dopamine levels. This leads to higher consumption of sugar to get the same level of reward. And like other drugs of abuse, withdrawal from chronic sucrose exposure can result in an imbalance in dopamine levels and be as difficult as going ‘cold turkey’ from them.”
Researcher Masroor Shariff said the study also put artificial sweeteners under the spotlight – “Interestingly, our study also found that artificial sweeteners such as saccharin could produce effects similar to those we obtained with table sugar.”