(photo credit: flickr, Jiuck)

Many of the cravings you experience that seem to come out of nowhere are often actually a physiological response to the stimulation of pleasure sensors in your brain.  And now researchers at the University of Southern California (USC) have come across another way our brains can be stimulated into eating.

According to new research presented at this year’s meeting of the Endocrine Society, having people view pictures of high-fat foods while they’re drinking sugar sweetened beverages activates the reward centers of the brain and makes the high-fat foods hard to resist. 

This study honed in on the brain’s responses to visual cues and how those cues increase hunger and desire for foods, particularly unhealthy foods.

Food on the brain

The researchers used functional magnetic resonance imaging (fMRI) to measure the brain responses of 13 obese, Hispanic women ranging in age from 15 to 25.  Research subjects were chosen based on their previous dispensation to food cues and limited to the Hispanic population because of its apparent high risk of obesity and type 2 diabetes.

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The women’s brains were scanned twice during the study--once while they viewed pictures of high-calorie foods, such as hamburgers, cookies, and cakes; and again while they viewed low-calorie foods such as fruits and vegetables.  After each viewing, the women were asked to rate their desire and hunger for sweet or savory foods on a scale from one to 10.

A sweet twist

This kind of testing has certainly been done before, but what makes this study distinctive is that halfway through the scans, the women were asked to drink 50 grams of glucose – about one can of soda – then asked to drink 50 grams of fructose.  Glucose and fructose are main ingredients in high fructose corn syrup and table sugar.

The researchers expected that the reward centers of the brain would be stimulated by the high-fat food images, but what they did not expect was that consuming sweetened beverages while viewing those images would increase the women’s hunger and desire for the savory foods. 

Science in the real world

This is hardly new information, however, especially to food advertisers.  Think of how often oversized pictures of hamburgers, French fries and milkshakes are splashed across television screens in an attempt to get the consumer from the couch to a fast food drive-through. 

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And the strategy works. Most fast food restaurants are not losing any business and America’s waistline continues to expand at an alarming rate.  This happens because food companies know how to target their advertising to exploit the human brain’s food triggers.

Your brain likes to eat

According to Dr. Arthur Frank, a leading weight loss specialist in Washington D.C., the human brain is constantly bombarded with triggers enticing the body to eat, which our bodies will naturally respond to because we are a species disposed to eating and storing energy.