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ARS Home » Plains Area » Grand Forks, North Dakota » Grand Forks Human Nutrition Research Center » Healthy Body Weight Research » Research » Publications at this Location » Publication #421755
Research Project: Approaches to Dietary and Physical Activity Guidelines Adherence

Location: Healthy Body Weight Research

Title: Preparation time does not reflect nutrition and varies based on level of processing

Author
item Hess, Julie
item COMEAU, MADELINE - Former ARS Employee
item PALMER, DANIEL - University Of North Dakota

Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/20/2025
Publication Date: 7/1/2025
Citation: Hess, J.M., Comeau, M.E., Palmer, D.G. 2025. Preparation time does not reflect nutrition and varies based on level of processing. Journal of Nutrition. 155(7):2416-2422. https://doi.org/10.1016/j.tjnut.2025.05.020.
DOI: https://doi.org/10.1016/j.tjnut.2025.05.020

Interpretive Summary: Americans spend approximately 40 minutes a day, on average, preparing food. While convenience is one of the top drivers of food choice, there are not well-accepted scientific methods for measuring the preparation time of a given menu or dietary pattern. This manuscript both proposes a method for evaluating the amount of time needed to prepare a menu and applies that method to more- and less-processed versions of a typical American diet. This study found that the time needed to prepare a food or meal does not reflect its nutrition. Foods that require more time to prepare such as homemade bread and dried beans may be considered less processed, but they provide similar nutrition to “ultra-processed” options such as bread purchased ready to eat and canned beans.

Technical Abstract: Background: Convenience is one of the top three drivers of food choice. The choice to consume nutrient-dense foods may rely, in part, on how much effort is required to obtain and prepare them for consumption. Objective: The objective of this study is to compare the time required to prepare 15 sets of meals with similar foods and nutrient content but different levels of processing, defined according to the Nova system. Methods: Each menu (the more- and less-processed Western menus) was divided into meal components and/or recipes. Two research staffers independently tracked the amount of time kitchen technicians used to make each step of each menu. Times were recorded to the centisecond and average times between the two timers were utilized as the final times for analysis. Results: For each day, the time required to make the less-processed Western menu (LPW) exceeded the more-processed Western (MPW) menu by amounts ranging from approximately 90 minutes (day 5) to 9 hours (day 1). The LPW had a 224% longer preparation time than the MPW (ß=3.2363; 95% C.I.[ 1.88394, 5.55954]; p=0.0004). Conclusions: The time required to prepare a food is not a reflection of its nutrient value. Foods that require more time to prepare such as homemade bread and dried beans may be considered less processed on the Nova scale but provide similar nutrition to “ultra-processed” options such as bread purchased ready to eat and canned beans.