In the academic literature, there is no consistent definition for junk food. Most studies assume that junk food is limited to certain categories such as salty snacks, desserts, and sweets. Consequently, products containing excessive amounts of saturated fat, energy, added sugar or salt but are not in these junk food categories have been excluded from such a definition. In recognizing these gaps, Elizabeth Dunford (University of North Carolina at Chapel Hill) and colleagues determined the proportion of energy, nutrients, and food components consumed by US adults that would be considered junk food using the Chilean law of food labeling and advertising criterion.
The study, which was published in The Journal of Nutrition, examined the amount of energy, sodium, sugar, and saturated fat consumed by US adults that would be classified as junk food using the Chilean criteria. Data from the National Health and Nutrition Examination Survey (NHANES 2015-2016 and 2017-2018 cycles) were utilized. The analyses included food components consumed by 10,001 US adults and junk food intake was examined using 3 age groups (19-29 years, 30-59 years, and > 60 years, 5 race/ethnic groups (Mexican American, other Hispanic, non-Hispanic white, non-Hispanic black, and other race) 2 genders (male and female), and 3 income groups (<185%, 185-350%, and >350% of the federal poverty level). Mean intake and proportion of energy, sugars, saturated fat, and sodium deriving from junk food overall and within each food category were calculated. The number of junk food items per day was calculated by dividing the number of items consumed that were classified as junk food using the Chilean criteria by the total number of food items consumed.
Overall, 47% of energy, 75% of total sugar, and 48% of saturated fat consumed by US adults was derived from junk food sources. Sugar-sweetened beverages were responsible for more than 40% of total sugar intake from junk foods. Non-Hispanic black adults had the highest mean energy, total sugar, and sodium intake deriving from junk foods, with non-Hispanic white adults having the highest saturated fat intake. Non-Hispanic black adults had the highest intake of total sugar deriving from junk food sources of sugar-sweetened beverages.
An important finding in this study was that foods from other categories, such as sandwiches, processed meats, ready-to-eat cereals, and bread products contributed to junk food intake in addition to the more typical items classified as junk food using the Chilean criteria. Focusing primarily on food and beverage categories generally considered to be junk food may not provide the full picture of where US consumers are deriving added sugars, sodium, and saturated fats. Last, race/ethnic disparities must also be considered when developing methods to reduce junk food consumption in the US population.
Elizabeth K Dunford, Barry Popkin, Shu Wen Ng, Junk Food Intake Among Adults in the United States, The Journal of Nutrition, Volume 152, Issue 2, February 2022, Pages 492–500, https://doi.org/10.1093/jn/nxab205.
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