PHILADELPHIA — An analysis of 10 fast-food restaurant chains in the United States found a decline in several health aspects from 1986 to 2016. Fast-food entrees, sides and desserts increased significantly in calories and sodium while entrees and desserts increased significantly in portion sizes, according to a study appearing online Feb. 27 in the Journal of the Academy of Nutrition and Dietetics.

“Our study offers some insights on how fast food may be helping to fuel the continuing problem of obesity and related chronic conditions in the United States,” said Megan A. McCrory, Ph.D., who works in the Department of Health Sciences at Boston University’s Sargent Hospital in Boston and was the lead investigator in the study.

Researchers collected data from The Fast Food Guide, published in 1986 and 1991, and from online sources in 2016. Dessert items had the largest increase in calories at 62 calories per decade. Entrees had the largest increase, 4.6% of the Daily Value per decade, in sodium. Portion size increased the most in entrees at 13 grams per decade and desserts at 24 grams per decade.

In more healthy findings, calcium increased significantly in entrees, at 1.2% of the Daily Value per decade, and desserts, at 3.9% of the Daily Value per decade, while iron levels increased significantly in desserts, at 1.4% of the Daily Value per decade. The variety of entree, side and dessert options increased by 226%. New or discontinued items tended to be less healthy than those available throughout the study period.

About 37% of U.S. adults, or those age 20 and over, consume fast food on any given day, according to the study. One meal with an entree and side provides an average of 767 calories, or close to 40% of a diet of 2,000 calories per day. Adding a caloric beverage increases the amount to 45% to 50%.