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Study: Fast Food Calorie Content Has Steadily Increased Over the Past 30 Years

3 minute read

The calorie content at the most popular U.S. fast food restaurants has shot up over the past three decades, according to a new study.

The study, published this week in the Journal of the Academy of Nutrition and Dietetics, compared food at 10 fast food restaurants: Arby’s, Burger King, Carl’s Jr, Dairy Queen, Hardee’s, Jack in the Box, KFC, Long John Silver’s, McDonald’s and Wendy’s. The study looked at the restaurants’ food in 1986, 1991 and 2016.

Researchers found that, on average, the calorie content of entrees went up by 30 calories a decade, while the calorie content of desserts went up by 62 calories a decade. Menu items also had a major increase in sodium content – about a 4.6% daily value increase per decade for entrees, the study said.

“Despite the vast number of choices offered at fast food restaurants, some of which are healthier than others, the calories, portion sizes and sodium content overall have worsened (increased) over time and remain high,” Megan McCroy, the study’s lead investigator, said in a statement.

Portion sizes for both entrees and desserts increased from decade to decade. The portion size of entrees went up by about 13 grams a decade, while desserts got 24 grams larger. The size of side dishes remained the same.

The study’s authors say that they chose to study fast food, in part, because Americans consume so much of it. Additionally, about 40% of American adults between 20 and 74 are obese, compared to about 13% of that age group between 1960 and 1962. Fast food accounted for about 11% of daily caloric intake in the U.S. between 2007 and 2010, and about 37% of U.S. adults consume fast food on a given day.

“Given the popularity of fast food, our study highlights one of the changes in our food environment that is likely part of the reason for the increase in obesity and related chronic conditions over the past several decades, which are now among the main causes of death in the U.S.,” McCroy said.

Customers were also offered more menu options over the period of this research. The number of entrees, sides and desserts increased by 226%, leading to an increase of about 22.9 menu items a year, the study said.

On average, the study suggests that new menu items were particularly unhealthy because entrees that were available during all three years didn’t have as big of an increase in sodium, energy or portion size.

McCroy said that she and the study’s authors feel that some policy changes, such as a requirement for fast food restaurants to display calorie content, are a step in the right direction. However they said fast food restaurants should begin to make bigger adjustments to promote healthier eating, such as reducing portion sizes.


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