6 Weird Effects Fast Food Has on Your Brain

You probably know it can blow up your waistline, but fast food may also have a surprising impact on your mood and mind.

You feel more impatient.


In a series of different experiments, Canadian researchers found that merely thinking about fast food can prime people to feel hurried. In another experiment, people who subconsciously viewed fast food logos and then read certain passages rushed through them more quickly than people who weren't exposed to the logos. "The way people eat has far-reaching—and often unconscious—influences on behavior and choices unrelated to eating," the study authors noted.

You splurge more.


Fast food may make us more likely to splurge, even when we're no longer in the restaurant. "We associate fast food with speed and instant gratification," says Sanford Devoe, an associate professor at the University of Toronto's Rotman School of Management, whose research found that households in neighborhoods with more fast food restaurants have lower levels of savings (even after accounting for variables like income, education, or ethnicity) than those with fewer fast food outlets. "When we see fast food logos or recall a recent experience eating at a fast food restaurant, we are put into a mental state of impatience that may make us more likely to spend on an immediate reward than save for something down the road," says Devoe.

You may be prone to depression.


People who eat a lot of fast food are 51 percent more likely to be depressed than those who steer clear of it, according to a Spanish study. The more burgers, pizza, and fries people ate, the greater their risk. More research is needed to see whether a fast food diet causes depression, or whether people with depression are simply more likely to dine on fast food. "Higher intake of fast food may very well increase risks of depression by causing poor health in general," said David Katz, MD, director of Yale University's Prevention Research Center in New Haven, Connecticut, told ABC News. "But depression may also increase fast food intake. We use the words 'comfort food' for a reason."

You eat too fast, and too much.


It's not the food that makes you eat quickly, research shows; it's the overall atmosphere when you eat out. Fast food restaurants are designed with speed eating in mind—and studies show the quicker you eat, the more calories you consume. Bright colors, like yellow and red, are mentally stimulating. Harsh lighting and loud music can also make you race through your meal. In fact, when Cornell researchers gave a Hardee's restaurant a fine-dining makeover with additions like soft lighting and jazz ballads, people ate almost 200 fewer calories and said they enjoyed their meals more than those who ate in the usual setting.

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Your brain gets hooked on sugar.


People think fast food is high in calories and fat, but many of us also don't realize how high in sugar certain fast food meals can be. In fact, it's often the meals that sound "healthy" that pack the most sweet stuff. For example, a Wendy's Garden Sensations Mandarin Chicken Salad contains 33 grams of sugar; a McDonald's Asian Salad has 22 grams. (Public health organizations recommend consuming no more than 24 grams of added sugar per day.) Recent research has indicated high sugar intake can lead to myriad health issues from heart disease to diabetes to obesity. Brain scans also reveal how sugar can be addictive: the more you eat, the more you're likely to keep craving it.

You may be more vulnerable to media messages.


According to a report by the Yale Rudd Center for Food Policy & Obesity, fast food brands spent $4.6 billion on advertising. Kids under age 6 viewed nearly three fast food ads daily on average, and teens between 12 and 17 saw nearly 5. According to Jennifer L. Harris, PhD, director of marketing initiatives at Yale's Rudd Center, in a PsychologyToday.com blog, adolescent brains are particularly susceptible to food advertising messages. Brain scans show that the reward centers of teen minds have a greater response to food advertisements and food logos, including fast food, compared with other types of ads, she wrote. What's more, she continued, "due to heightened reward sensitivity, adolescents are not biologically equipped to forgo these tempting offers in the short-term for greater rewards in the future (such as good health)."

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