By Chelsea Karnash

PHILADELPHIA (CBS) – Think fast food has gotten healthier?

You might want to put down those coconut oil-fried, sea salt-coated french fries and think again.

According to a new study published in the American Journal of Preventative Medicine, the nutritional quality of fast food produced by the eight most common fast food chains in the United States has improved only marginally over the last 14 years.

Researchers analyzed food from McDonald’s, Burger King, Wendy’s, Arby’s, Taco Bell, KFC, Dairy Queen and Jack in the Box from 1997/1998 to 2009/2010 and found that there was only a three point score increase on the Healthy Eating Index, or HEI-2005.

Additionally, the scores did not improve for fruits and vegetables — though they did for meats, saturated fat and added sugar – and actually declined for sodium and milk and dairy products.

KFC showed the largest improvement in nutritional quality with a nine point increase, and six of the chains did show improvement in the quality of their food.

But with an average score of 48, all eight fast food chains still fell short of that of the average Americans diet, which ranks a 55 out of 100.

According to the study’s authors, while “modest improvements in average nutritional quality of menu offerings across eight fast-food restaurant chains were observed,” there is room for plenty of improvement, especially “considering that fast food is ubiquitous in the U.S. diet.”

To see the full study, visit:

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