The percent of energy from ultra-processed foods in the diet is an indicator that provides an understanding of changing dietary patterns, cultural preferences, and diet quality. Low- and middle-income countries are rapidly undergoing a nutrition transition that is characterized by changes in dietary patterns and nutrient intakes, resulting in higher consumption of energy-dense and processed foods (Popkin et al., 2004). Ultra-processed foods are foods that undergo industrial processes (e.g. salting, sugaring, frying, and curing) that extend shelf life, make food extremely palatable, and make food that is designed to be ready-to-consume (Monteiro et al., 2018).
Diets rich in ultra-processed foods may promote obesity and chronic disease because these foods typically have high energy density, they are low in fiber, micronutrients, and phytochemicals; and are high in unhealthy fats and sugars (Ludwig, 2011). In addition, they are highly palatable and come in large portion sizes (Ludwig, 2011).
Method of Construction
Data used to construct this indicator should come from food consumption surveys of individuals, such as quantitative 24-hour Dietary Recalls, Weighed Food Records, and quantitative Food Frequency Questionnaires (FFQs) designed specifically for this purpose. See the table below for a more detailed explanation of the classification based on the level of food processing (Monteiro et al., 2018). A food composition table is used to estimate the total energy (kcal) intake over the day from all foods and beverages recalled in the survey, including the energy provided by ultra-processed foods. The indicator is then constructed using the formula below:
Food classification by the level of processing (Monteiro et al., 2018)
Group 1. Unprocessed or minimally processed foods:
Definition: Unprocessed foods (in nature) are edible parts of plants, animals, fungi, algae, and water. Minimally processed foods are unprocessed foods altered by certain (Monteiro et al., 2018).
Processes: Cleaning, drying, crushing, grinding, fractioning, filtering, roasting, boiling, non-alcoholic fermentation, pasteurization, refrigeration, chilling, freezing, placing in containers and vacuum-packaging (Monteiro et al., 2018).
Goal of processing: Preservation, safety, and palatability. Unprocessed or minimally processed foods are often prepared and cooked in combination with processed culinary ingredients at home and in restaurants (Monteiro et al., 2018).
Group 2. Processed culinary ingredients:
Definition: Processed culinary ingredients, such as oils, butter, sugar, and salt, are substances produced from Group 1 foods or from nature (Monteiro et al., 2018).
Processes used to produce culinary ingredients: Pressing, refining, grinding, milling, and drying (Monteiro et al., 2018).
Goal of its use: To prepare, season, and cook hand-made dishes and meals of Group 1 food (Monteiro et al., 2018.
Group 3. Processed foods:
Definition: Processed foods are made by adding culinary ingredients to unprocessed and minimally processed foods (Monteiro et al., 2018).
Processes: Preservation, cooking, and, non-alcoholic fermentation (Monteiro et al., 2018).
Goal of processing: To increase the durability of unprocessed or minimally processed foods, or to change and improve their sensory qualities (Monteiro et al., 2018).
Group 4. Ultra-processed foods:
Definition: Ultra-processed foods are formulations made from substances derived from foods and additives, with little if any intact Group 1 food (Monteiro et al., 2018).
Processes: A series of processes with no domestic equivalent is required to make ultra-processed foods, for example, hydrogenation, extrusion, and molding. These foods are made with culinary ingredients and other substances not used in culinary preparations such as hydrogenated or interesterified oils, soya protein, maltodextrin, and inverted sugars. The additives include preservatives, antioxidants, and stabilizers also used in processed foods, and dyes, stabilizers, flavor enhancers, non-sugar sweeteners, glazing agents, etc, that imitate or enhance the sensory qualities of foods (Monteiro et al., 2018).
Goal of processing: To create durable, convenient, ready-to-consume, hyper-palatable, and branded low-cost products (Monteiro et al., 2018).
This indicator has been proposed by the International Network for Food and Obesity/Non-Communicable Disease Research, Monitoring and Action Support (INFORMAS) as an indicator that can be used globally to monitor changes in population diet quality over time and across countries (Vandevijvere et al., 2013). This indicator enables an analysis of the relative contribution of ultra-processed foods to overall dietary energy intakes based on data from individuals and therefore can be used to assess differences between sub-population groups based on geographic location, income group, and various other demographic characteristics.
Strengths and Weaknesses
This indicator measures the relative contribution of ultra-processed foods to overall dietary energy intakes; it does not provide information on the consumption of individual nutrients or specific foods. Since ultra-processed foods can often be consumed outside of the home, survey data used for this indicator that do not include detailed information about food consumed outside of the home will underestimate the percent of energy from ultra-processed foods. It should also be noted that this indicator has not yet been thoroughly tested (Vandevijvere et al., 2013).
Data from individual quantitative 24-hour Dietary Recalls, Weighed Food Records and FFQs designed for this purpose can be used to construct this indicator. This indicator could also be constructed at the household level using Household Consumption and Expenditure Surveys (HCES) that have an appropriate level of disaggregation of foods and include detailed information on foods consumed away from home (Smith et al., 2014).
The Food and Agriculture Organization/World Health Organization's Global Individual Food Consumption Data Tool (FAO/WHO GIFT) is a source for individual-level quantitative dietary data. FAO/WHO GIFT aims to make publicly available existing quantitative individual food consumption data from countries all over the world. National or regional Food Composition Tables should be used to identify the energy content of the foods and can be found at FAO's International Network of Food Data Systems (INFOODS) or the Agricultural and Food Systems Initiative World Nutrient Databases for Dietary Studies (WNDDS).