Is advertising triggering obesity epidemic
London: A picture not only can say a thousand words, but it can also be worth a thousand calories, as a new study has found that images of fatty food can trigger your hunger pangs, leading to overeating and obesity. Scientists at the University of Southern California in the US found that just looking at images of high calorie food stimulates the brain`s appetite control centre and results in an increased desire for food.
"This stimulation of the brain`s reward areas may contribute to overeating and obesity," said Dr Kathleen Page, who led the study. "We thought this was a striking finding, because the current environment is inundated with advertisements showing images of high-calorie foods," he was quoted as saying by the Daily Mail.
In the study, the researchers used functional magnetic resonance imaging (fMRI) to look at brain responses of a group of obese young Hispanic women, who were at risk of continuous weight gain. Each participant had two fMRI scans as they viewed images of high calorie foods, such as ice cream and cupcakes , as well as low calorie foods like fruit and veg, and non-food pics.
After each set of images, participants rated their hunger and desire for either sweet or savoury foods on a scale of one to ten, drinking 50 grams of glucose on one occasion and fructose on another halfway through the scans. As fMRI measures blood flow to the brain, regions with increased blood flow indicated greater activity. The team measured which brain regions were activated when viewing images and how sugar intake influenced this.
Results showed simply viewing high calorie food images activated brain regions that control appetite and reward , compared to pictures of non foods. Viewing pictures of high calorie food also significantly increased ratings of hunger and desire for sweet and savoury foods, the researchers said. They also found ratings of hunger and desire for savoury food were higher after drinking either sugar beverage – but fructose produced greater activation of brain regions involved in reward and motivation for food.