Food frequency questionnaires do not typically include the level of detail necessary to characterize the level of processing used to create the foods consumed.  Considering evidence is developing to suggest that ultraprocessed food consumption is associated with multiple negative health effects, it is necessary to better estimate their intake.  Work performed by Steele and colleagues to standardize the application of the Nova classification system of food processing is reported in the January 2023 issue of The Journal of Nutrition.

Initially the Nova classification system was applied to the 2001-2018 What We Eat in America data from NHANES using a reference approach.  The percentage of energy consumed from each of the four Nova groups (unprocessed or minimally processed; processed culinary ingredients; processed foods; or ultraprocessed foods) was calculated for non-breastfed participants over 1 year of age in the 2017-2018 WWEIA data.  Sensitivity analyses were conducted using alternative approaches that opted for more or less degrees of processing for ambiguous items.

Using the reference approach, energy derived from ultraprocessed foods was 58.2%, with unprocessed or minimally processed foods contributing 27.6%.  The remainder of energy intake was derived from processed culinary ingredients (5.2%) and processed foods (9.0%).  Dietary energy contributed by ultraprocessed foods ranged from 53.4% to 60.1% within the 4 sensitivity analyses.  The authors conclude by stating the reference approach provides a means to promote standardization and compatibility among future research studies.


Steele EM, O’Connor LE, Juul F, Khandpur N, Baraldi LG, Monteiro CA, et al.  Identifying and estimating ultraprocessed food intake in the US NHANES according to the Nova classification system of food processing.  Journal of Nutrition, Volume 153, Issue 1, January 2023, Pages 225-241.

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