Ultra-processed foods have been in the news recently. Opponents say they are the cause of obesity and diabetes. Others say they are not as bad as people make them out to be. So, what are ultra-processed foods, and how can we as consumers understand and evaluate the term?
What are Ultra-Processed Foods?
The term ultra-processed foods comes from the NOVA classification system of food. The NOVA classification system divides foods into four categories: unprocessed/minimally processed foods, processed culinary ingredients, processed foods, and ultra-processed foods. The assumption of this classification system is that nutrition is based more on how much processing a food went through than the ingredients and nutrients it contains.
Four Categories in the Nova Classification system: Unprocessed to Ultra-Processed Foods
Unprocessed/minimally processed foods are single foods in their raw form, such as fruits, vegetables, eggs, beef, and chicken. Minimally processed foods are these foods that are cut into smaller pieces or packaged, such as a pealed orange or meat that is butchered and frozen.
Processed culinary ingredients are single-ingredient foods derived from unprocessed or minimally processed foods. Examples are oil, whole grain flour, and fruit juice.
Processed foods are made by adding processed culinary ingredients to an unprocessed food. These include canned vegetables or fish, salted meat or fish, and fruit in syrup.
Ultra-processed foods is the final category. These foods use a variety of processed culinary ingredients and are produced with industrial techniques. Examples are fruited yogurts, store-bought pastries, soda, instant soups, and frozen dinners.
What does the Research Say about Ultra-Processed Foods?
There are many studies that looked to see if there is an association between eating ultra-processed foods and outcomes such as obesity, heart disease, diabetes, and cancer. In most studies, a link was found between higher intake of ultra-processed foods and obesity, heart disease, diabetes, and cancer. It is important to understand that these studies were all observational--they looked at what people were already eating and then looked at their health. They did not assign one group to eat unprocessed foods and another group to eat ultra-processed foods.
There is one interesting study that did assign participants what to eat. They provided people with diets that were similar in salt, fat, sugar, and fiber, but one diet was from ultra-processed foods, and one was from homemade foods. Participants were allowed to eat what they wanted. They found that the group that ate the ultra-processed foods ate on average 500 more calories per day than the group that ate the unprocessed food. It is still unclear why people who ate the ultra-processed foods ate more calories. I think it points to the fact that there is a lot more that needs to be learned about this topic.
How can we understand the link? Perhaps the reason that ultra-processed foods are linked to adverse health outcomes is because people who eat ultra-processed foods are eating more calories per day. It is also possible that diets that are high in ultra-processed foods are higher in certain nutrients that are linked to health problems, such as salt, sugar, and saturated fats. It might not be the level of processing that the food undergoes, but rather what is in the food.
What is the Bottom Line about Ultra-Processed Foods?
I think that knowing that a food is ultra-processed can be a signal to you to look a bit closer. Consider checking the nutrition facts label to see the sodium, sugar, saturated fat, or fiber content. You can compare a few options of similar foods to decide which one you'd like to eat.
There are a few good theories as to why ultra-processed foods are linked to poor health outcomes. It might be that it leads to higher calorie intake, and it might be because these foods are higher in sodium or sugar. I think that over time and with more research, the link will become clearer.
Despite the buzzword status of "ultra-processed," it is helpful to note that not much new was discovered in these studies. The results are in line with current nutrition recommendations. For a long time, the recommendations have been to eat more fruits and vegetables and less foods with added salt and sugar. From a practical standpoint, following the general nutrition advice that has been given by reputable sources is a good idea.
This is a fascinating article!