Pamela Peeke, MD, MPH, FACP wrote an article for IDEA Health and Fitness Association, “Food and Addition: The Dopamine Made Me Do It.”
Peeke’s article caught my attention. At times, most of us struggle with food cravings and sugar high’s, so why not understand it at a deeper level, right?! Here’s what she has to say:
To date, procreative activities have maintained their primal prerogative without too much deviation from nature’s blueprint. Food production and consumption, on the other hand, have fallen prey to psychosocial, cultural and environmental factors that increase our collective girth and make us more vulnerable to disease.
Researchers have recently uncovered a critical clue to help explain this problem—a link between food and addiction.
“I can’t get off the stuff.” “I need a hit.” “I’ve got to detox.” “Withdrawal is hell.” Fitness, nutrition and health professionals have heard this kind of addiction vernacular for years. However, we’re not talking about drugs, alcohol or cigarettes—this is about food. The big culprits are the hyperpalatables—sugary, starchy, fatty and salty foods. Is there a relationship between food and addiction? Can food products hijack the reward system in much the same way as drugs? Yes, according to newly published data and a growing chorus of scientists.
Central to this burgeoning research is the role of dopamine, the neurotransmitter that
- signals when rewards are present;
- motivates us to seek rewards;
- promotes exploring and learning about rewards; and
- maintains awareness about reward-related cues.
Cocaine and heroin target and hijack this reward system. So do appetite-controlling hormones, leading a growing number of researchers to consider obesity from the standpoint of addiction neuroscience (Dagher 2012).
Dopamine is actually dispersed throughout the brain. Ninety percent of the dopamine neurons in the ventral tegmental area (VTA) become stimulated when we’re about to eat. The VTA reaches out to the rest of the brain via countless axons to stimulate dopamine secretion in several brain regions, including the mesolimbic and mesocortical dopamine systems. The mesolimbic system reaches into the nucleus accumbens (the site of reward, pleasure and addiction), the amygdala (where emotions are processed and remembered) and the hippocampus (a site that converts short-term memory to long-term memory) (Volkow & Wise 2005). In an effort to understand whether certain foods exert the same kind of addictive effect on the reward system as drugs, scientists have turned their attention to the reward centers in normal and overweight humans.
Leading the charge is Nora Volkow, MD, director of the National Institute on Drug Abuse. In 2001, Volkow and her team used PET scans and radioactive chemicals that bind to dopamine receptors (Wang et al. 2001). Their research revealed that obese people had far fewer dopamine receptors in the brain’s striatum, or reward center, and therefore had to eat more to experience the same reward, or “high,” as average-weighted individuals.
Did these people already have fewer receptors—predisposing them to weight gain—or did they once have a normal number of receptors, which through repeated exposure was down regulated? The answer is both.
There is far more to this article. It seems very well researched and explained, so please read the whole article it’s worth your time!