Ultra-processed foods are making us fat fast: the food facts that make us want more
In recent years, the ultra-processed have become one of the "public enemies" of food (and nutrition) in developed and on-going societies. There are many reasons for this, but in this world it has always been difficult to separate "culinary fads" from informed nutritional recommendations. This happened, for example, with the relationship between obesity and these foods.
Something that has been on the table for decades, but that we needed to have black on white. We already have it. A small but very solid nutritional study gives a handful of fundamental keys to understanding what was happening there.
What are we talking about when we talk about processed and ultra-processed?
The NOVA system, one of the references in this matter, classifies all foods into four main groups according to the nature, scope and purpose of the processing to which they have been subjected. We could say that it follows a "constructive" logic: 'Group 1' is unprocessed or minimally processed foods. Basically they are edible parts of plants, animals, fungi and algae.
The "minimally processed" refers to the elimination of inedible parts, their drying, crushing, partitioning, filtering, pasteurization, refrigeration, packaging, etc ... Processes that, in general, do not add substances such as salt, sugar, oils or other fats to the original product. The latter type of substances are part of 'Group 2', processed culinary ingredients that are extracted from the former (by pressing, refining or other methods), but are not usually consumed directly.
The 'Group 3' are processed foods and arise, basically, from processing products of 'Group 1' with those of 'Group 2'. As has been emphasized many times, these types of foods do not have to be unhealthy in themselves. The vast majority of processed products carry very few ingredients, those necessary for cooking or helping to preserve the product.
And lastly we come to ultra-processed products which are products that are made from 'Group 2' and 'Group 3' food, but have no trace of fresh food products. They are usually industrial formulas with many ingredients and are usually made to be consumed without further ado (so that they can replace a complete meal).
Ultra-processed and health
In the last decades and in the hands of many other social changes, the ultra-processed have supposed a whole tectonic movement in the feeding of modern societies. Today, this type of food represents more than 50% of the calories that Americans consume and, as more and more countries add to what we could call 'cultural globalization', the phenomenon does not stop growing in every more and more regions of the world.
There was no shortage of experts who warned of the relationship between this new diet and health. A few months ago, a group of researchers from the University of Paris 13 published an epidemiological study in which they examined for two years the consumption habits of almost 45,000 French adults (over 45 years old).
Even in an environment like these, where ultra-processed foods made up 15% of the diet, researchers found a direct statistical connection between increased consumption of ultra-processed foods and an increased risk of premature death from all causes, especially from cancer and cardiovascular diseases. This is something we constantly see in all the countries where the problem is studied.
In other words, large epidemiological studies have been warning us that eating large amounts of ultra-processed foods is associated with more health problems, less quality of life and, finally, a greater probability of premature death. But they were, for logistical reasons, epidemiological studies. We now have the first randomized clinical trial studying the impact of ultra-processed diet on health and the results are tricky.
What happens if we eat ultra-processed?
In this case, a research group from the US National Institute of Health (NIH) selected 20 men and women and housed them for four weeks in a residence. There they were divided into groups and some were fed a diet based on ultra-processed foods and others with a diet based on unprocessed foods.
The idea was to make two diets that had roughly the same amount of calories, carbohydrates, fats, and sugar. Of course, participants were allowed to eat as much as they wanted. During these weeks, the researchers not only prepared all the foods the participants ate, but tracked down each bite they took and carefully analyzed the effects of those foods on their weight, body fat, hormone levels, and other biomarkers.
The study found that people consistently consumed more calories and gained weight when given a diet rich in ultra-processed foods. And very fast. According to the researchers' data, participants in this variant consumed an additional 500 calories a day (almost all in carbohydrates and fats), which resulted in a weight gain of more than a pound in 2 weeks.
Why? The authors acknowledge that it needs to be studied in more detail, but they point out that the hypothesis that best fits the results is that the composition of the ultra-processed foods caused a mismatch in the levels of hunger hormones (such as the YY peptide or ghrelin ). In other words, a vicious circle would occur in which ultra-processed products would generate more hunger than unprocessed ones.
A health problem, but also a social one
This constitutes a huge health problem that is fattened by people of lower socioeconomic levels who, according to the data we have, tend to consume more ultraprocesses in the same way that they also tend to smoke more, exercise less and participate in other consultations of risk.
In this case, the NIH researchers insist that solutions must be found that do not demonize processed foods because there are many people who depend on them for their daily diet. Keep in mind that the unprocessed diet used in the NIH study is worth 40 percent more than the ultra-processed diet. That is, we are facing a perfect storm: harmful, cheap, comfortable food that generates the conditions to perpetuate its consumption. It is something to talk about as soon as possible.