New research in pigs reveals that consuming sugar alters the brain’s reward processing circuits in a similar way to addictive drugs.
Whenever we learn something new or experience something enjoyable, the Reward system becomes activated. Using natural brain chemicals, several areas of the brain communicate with each other to help us learn and repeat behaviors that improve our knowledge and well-being.
Based heavily on the neurotransmitter dopamine, the reward system helps explain several essential human experiences, such as falling in love, sexual pleasure, and spending time with friends.
However, certain substances, such as drugs, hijack the brain’s reward system, activating it “artificially.” Telling the brain to repeat pleasure-seeking behavior all the time is the mechanism of addiction.
But is sugar such a substance? And if so, does that help explain the sweet cravings?
An American scientist by the name of Theron Randolph coined the term “food addiction” in The ’50s to describe compulsive consumption of certain foods, such as milk, eggs, and potatoes.
Since then, studies exploring this concept have yielded mixed results, and some experts argue that talking about food addiction is a bit of a stretch.
New research is helping to shed light on the issue, such as Michael Winterdahl, associate professor in the Department of Clinical Medicine at the University of Aarhus in Denmark, and colleagues have examined the effect of sugar consumption on food circuits. reward in the brains of pigs.
The researchers published their results in the journal Scientific Reports.
Scientists analyzed the effects of sugar intake on seven female mini-pigs from Göttingen, using complex PET imaging techniques with opioid receptor agonists and dopamine receptor antagonists to examine reward systems animal brain.
The team gave minipigs access to a sucrose solution for 1 hour for 12 consecutive days, then resumed testing 24 hours after the last dose of sugar.
In a subgroup of five minipigs, the team applied an additional PET scan after the first exposure to sugar.
“After just 12 days of consuming sugar, we could see major changes in the brain’s dopaminergic and opioid systems,” reports Winterdahl.
“In fact, the opioid system, which is the part of brain chemistry associated with well-being and pleasure, has already been activated after the very first take,” added the lead author of the study.
More specifically, there were changes in the “striatum, nucleus accumbens, thalamus, tonsil, cingulate cortex, and prefrontal cortex” after taking sugar.
The results, the researchers conclude, imply that “foods high in sucrose influence the brain’s reward circuits in a similar fashion to those seen when addictive drugs are used.”
The principal investigator explains that the results contradict his initial expectations. “There is no doubt that sugar has several physiological effects, and there are many reasons why it is not healthy.”
“But I doubt the effects of sugar on our brain and behavior, [and] I had hoped to kill a myth. He goes on to focus on the addictive aspects of sugar consumption.
“If sugar can change the brain’s reward system after just 12 days, as we saw in pigs, you can imagine that natural stimuli, such as learning or social interaction, are pushed to the background and replaced with sugar and / or other “artificial” stimuli. ”
“We’re all looking for the dopamine rush, and if something gives us a better or bigger kick, then that’s what we choose,” he says.
The researchers also explain their choice of minipigs as a model for studying the effects of sugar on the brain.
They say previous studies have used rats, but even though these rodents have a fondness for sugar, their homeostatic mechanisms – which help regulate weight gain and metabolism – “differ considerably from those of humans.”
“It would, of course, be ideal if the studies could be done on humans themselves, but humans are difficult to control and dopamine levels can be modulated by a number of different factors,” says Winterdahl.
“They are influenced by what we eat, whether we play games on our phones or enter a new romantic relationship in the middle of the trial, with the potential for the wide variation in the data.”
“Pork is a good alternative because its brain is more complex than a rodent and large enough for imaging deep brain structures using human brain scanners. ”