Is Fast-Food Really That Bad for You? Many Underestimate Number of Calories in Meals

It might not seem like news, but apparently, fast-food is bad for you. And some of us didn't realize how bad? (No.)

Well, yes. As we're unfortunately not characters in the Woody Allen film "Sleeper," statistics show that people really are that stupid-ready to gobble up high-calorie goodies all day despite expanding waist-bands and heart attacks.

Yet, despite the overwhelming obesity epidemic in this country alone, many don't realize just how unhealthy this stuff is. For instance, teens underestimate the calories in the junk their eating by 34 percent. And, to make matters worse, parents of school-aged children do the same at 23 percent with adults at 20 percent, according to lead researcher Jason Block of Harvard Medical School and Harvard Health Care Institute.  

Block and colleagues surveyed about 3,400 adults, teens and parents of school-age children who visited 89 fast-food restaurants, including McDonald's, Burger King, KFC, Subway, Dunkin' Donuts and Wendy's. People were asked to estimate the calories in their meals, then the researchers collected their receipts and figured out how many calories the meals actually contained. The study was conducted in 2010 and 2011.

Among the findings, published Thursday in BMJ, a journal of the British Medical Association:

• One-fourth of participants underestimated the calories in their meals by at least 500 calories.
• Teens' fast-food orders contained an average of 756 calories, but they underestimated their orders by an average of 259 calories.
• Adults ordered meals containing an average of 836 calories, but they underestimated by 175 calories.
• School-age children got meals that had an average of 733 calories, but their parents' guestimates were 175 calories too low.
• Diners at Subway underestimated the calories in their orders by a larger amount than diners at McDonald's, Burger King, KFC, Wendy's and Dunkin' Donuts.

"These large underestimations show that diners don't really know what they are eating in terms of calorie content, and they need this information to help guide their choices," Block said, according to The Detroit Free Press. "They could get it from the company websites or in some other form in the restaurants, such as wall posters, napkins or cups, but soon they'll be directly faced with it when they see it on the restaurant menu boards before they order their meal. Customers can already do this at McDonald's -- and in some cities."

The study was funded in part by the Robert Wood Johnson Foundation.