Characterizing Ultra-Processed Foods by Energy Density, Nutrient Density, and Cost

Area of Science:

• Nutrition Science
• Food Policy
• Public Health

Background:

• The NOVA classification system categorizes foods into four groups: ultra-processed, processed, unprocessed, and culinary ingredients.
• Ultra-processed foods constitute over 60% of the total energy intake in the United States.
• Understanding the characteristics of ultra-processed foods is crucial for public health initiatives.

Purpose of the Study:

• To analyze ultra-processed foods based on their energy density, nutrient density, and monetary cost.
• To compare the characteristics of ultra-processed foods with other food categories.

Main Methods:

• Utilized the Fred Hutch (FHCRC) food frequency questionnaire (FFQ) with 384 foods, assigning them to NOVA categories and USDA MyPyramid food groups.
• Quantified energy density (kcal/g) and nutrient density using the Nutrient Rich Food index (NRF9.3).
• Collected food prices from local supermarkets between 2004 and 2016 to examine price trends.

Main Results:

• Ultra-processed foods were predominantly found in grains, fats and sweets, dairy, and beans, nuts, and seeds categories.
• Compared to unprocessed foods, ultra-processed foods exhibited lower nutrient density (NRF9.3: 21.2 vs. 108.5 per 100 kcal) and higher energy density (2.2 vs. 1.10 kcal/g).
• Ultra-processed foods were significantly cheaper per calorie ($0.55 vs. $1.45 per 100 kcal) and showed slower price increases over the study period.

Conclusions:

• Ultra-processed foods are characterized by high energy density, low nutrient density, and low cost.
• The low economic cost of ultra-processed foods may be a contributing factor to adverse health outcomes.
• Dietary guidelines should incorporate considerations of food processing and its economic implications in food choices.