'Ultraprocessed' Foods Make Up More Than Half of Americans' Diets
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Calories from "ultraprocessed" foods make up more than half of all calories in the average American diet and account for nearly 90 percent of all added sugars, a new study finds.

Ultraprocessed foods are defined by the researchers as "formulations of several ingredients" which, besides sugar, salt, oils and fats, include additives such as flavors, colors, sweeteners and emulsifiers.

This ultraprocessed classification includes foods such as breads; soft drinks, fruit drinks and milk-based drinks; cakes, cookies and pies; salty snacks; frozen foods; and pizza and breakfast cereals, according to the study, which was published today (March 9) in the journal BMJ Open.

The researchers also found that the more ultraprocessed foods a person eats, the more likely he or she is to exceed the recommended daily limit for added sugars in the diet, according to the study. (The new Dietary Guidelines for Americans recommend that calories from sugars should account for no more than 10 percent of a person's daily calories. For someone who eats 2,000 calories a day, this would mean no more than 200 calories should be from added sugars.) [Diet and Weight Loss: The Best Ways to Eat]

"Limiting the consumption of ultraprocessed foods may be a highly effective way to decrease added sugars," the researchers, led by Euridice Martinez Steele, a researcher at the University of São Paulo in Brazil, wrote in the study. Consuming too much added sugar is "most likely contributing" to growing levels of obesity, Type 2 diabetes and heart disease, they added.

In the study, the researchers used data from the 2009-2010 National Health and Nutrition Examination Survey (NHANES). Specifically, they looked at the survey responses of more than 9,300 participants who had provided data on the foods they had eaten in a 24-hour period. (One limitation of the study, the researchers noted, is that people may not accurately report the foods they consumed in the 24-hour period.)

In addition to ultraprocessed foods, the researchers also looked at the amounts of unprocessed or minimally processed foods, processed culinary ingredients and processed foods in the average American's diet.

Unprocessed or minimally processed foods include meat, fruits, vegetables, fish and grains; and processed culinary ingredients include table sugar, plant oils and animal fats. Processed foods (which were defined as unprocessed or minimally processed foods manufactured with added salt, sugar or other culinary substances) include such foods as cheese, canned foods and salted meats.

The researchers found that unprocessed or minimally processed foods contributed to, on average, 29.6 percent of a person's total daily calories; processed culinary ingredients contributed to, on average, 2.9 percent of a person's total daily calories; and processed foods contributed to, on average, 9.4 percent of a person's total daily calories, according to the study.

Ultraprocessed foods, on the other hand, accounted for, on average, 57.9 percent of a person's total daily calories, or nearly 3 out of every 5 calories consumed, the researchers wrote in the study.

In addition, only those who reported eating the least amount of ultraprocessed foods (accounting for, on average, 28.9 percent of their daily calories) were found to meet the recommended limit of getting less than 10 percent of their daily calories from added sugar, according to the study. 

The researchers recommend that Americans reduce their intake of ultraprocessed foods — doing so, they argue, would increase the intake of more healthful, minimally processed foods such as milk, fruits and nuts, as well as freshly prepared dishes with whole grains and vegetables, which would produce health benefits beyond cutting out added sugar. 

Follow Sara G. Miller on Twitter @SaraGMiller. Follow Live Science @livescience, Facebook & Google+. Originally published on Live Science.