Experts have long debated the possibility of food addiction; many believe that a substance necessary for survival cannot be classified addictive. But with the proliferation of 24-hour grocery stores, tasty but nutritionally void convenience foods and even a “foodie” culture, it can be argued that the general attitude towards food in developed countries extends far beyond merely surviving.
A new study entitled Effects of dietary glycemic index on brain regions related to reward and craving in men published in the NCBI Journal, tested the effects of consuming high-glycaemic and low-glycaemic index milkshakes on 12 healthy, overweight men. Low-glycaemic foods, such as vegetables and whole grains, are associated with minimal fluctuation of blood sugar levels and longer duration of satiety. High-glycaemic index foods (junk foods) which contain refined sugar and starch–and lots of it–are associated with a rapid rise and fall of blood sugar levels.
The milkshakes were distributed to the study’s participants in random order over different days. Each day, after four hours had passed the participants who’d consumed the high-glycaemic shake were hungrier than the others. The researchers also performed fMRI on the brains of the participants. According to Dr. Belinda Lennerz, an author on the study, “The images revealed intense activation of the nucleus accumbens, a critical brain area in the dopaminergic, mesolimbic system that mediates pleasure eating, reward and craving. Similar activation patterns have been found in people after consumption of addictive substances, such as heroin or cocaine.”