UFRJ study investigates the effects of the component consumed in excess of processed and ultra-processed foods on health
By (UFRJ)
Citrus fruits such as lemon, lime, orange, tangerine and many others are rich in a salt called citrate.
Derived from citric acid, this salt is a central molecule for the functioning of the body. It participates in cellular metabolism, transforms nutrients into energy and helps with the chemical balance of blood and urine and plays an important role in bone and kidney health.
As it is a natural component of several foods, citrate is considered safe from a toxicological and nutritional point of view. Therefore, there are no limits on its use established by any regulatory agency in the world.
Although it is a natural component of almost all foods, especially citrus fruits, the effects of excessive consumption are little known. The amount of citrate added to processed and ultra-processed foods and its consumption by the population has no control.
Just to give you an idea, the amount of citrate in 200 ml of industrialized orange juice is more than 10 times higher than the amount in fresh orange juice.
Citrates in food additives
The research group then decided to study the effects of citrates, which are used as food additives and which are present in the vast majority of foods with some degree of processing.
In addition to citrus fruits, citrates are found in boxed milk, chocolate drinks, soft drinks, energy drinks, ready-to-eat teas, boxed juices, sports drinks, cream cheese, processed cheeses and a multitude of other products. Sodium, potassium, iron and citric acid citrates were studied.
These additives are used as acidity regulators, stabilizers, emulsifiers and preservatives. They are present in the vast majority of foods that have undergone some degree of processing.
Even though it is not possible to know the average citrate intake, it is estimated that intake more than tripled with the dietary transition. The dietary transition is a process of change in human habits that occurs throughout the world.
In general and in a very drastic way, we stop eating foods in nature and we are increasingly consuming foods with some degree of processing.
This occurs due to several factors, including population growth and the consequent need for greater food production and longer conservation.
From natural to ultra-processed
In this context, foods began to be classified according to the degree of processing. This classification, called NOVA and developed by researchers at , labels foods into four groups:
In the 1st group, there are foods in nature or minimally processed. These foods are obtained directly from plants or animals such as fruits, vegetables, meat, eggs without alteration, or minimally altered such as rice, beans, pasteurized milk, coffee and flour.
The 2nd group includes processed culinary ingredients. Substances obtained from group 1 foods or nature, used for seasoning and cooking. This group includes oils, fats such as butter and lard, salt and sugar.
The processed food group includes products manufactured by adding culinary ingredients (group 2) to foods in nature (group 1). We can mention canned vegetables, artisan breads, cheeses and fruit in syrup.
Industrial formulations made entirely or mostly with substances extracted from food (oils, fats, sugar, starch, proteins), hydrogenated or modified, containing little or no food in nature and many additives (colorings, flavors, etc.) are considered ultra-processed. This group includes soft drinks, packaged snacks, instant noodles and stuffed biscuits.
Empty calories
In general, the greatest concern regarding the quality of food is linked to its nutritional value. Thus, the “demonization” of ultra-processed foods has focused on what they call empty calories.
These empty calories are associated with excess sugars, especially refined sugar and fats. And even alcohol, contained in alcoholic beverages, is also included in the empty calories category due to its increased consumption with the dietary transition and the popularization of ultra-processed foods.
It is a fact that the consumption of these empty calories is associated with several health problems. In particular, excessive weight gain, leading to overweight and obesity.
Much has been associated between excessive calorie consumption, especially empty calories, and the global overweight pandemic, which does not discriminate gender, social class or even age.
And an important issue that we identified in recent work is that consuming these empty calories in excess, even if sporadically, like just once a week, has negative consequences for health.
And unfortunately, today, children are among the biggest victims of the consumption of these empty calories and the overweight pandemic.
Excess citrates
It is already established by science that the fate of consumed citrate points to its use in the mitochondria, where it is oxidized to produce energy, through the Krebs cycle.
However, within cells, citrate is used to produce fats, cholesterol and promote the acetylation and modification of proteins and nucleic acids. Citrate plays a central role in metabolic regulation and epigenetic effects.
Then, studies were dedicated to the effects of increased citrate consumption on the metabolism and physiology of mice.
The initial hypothesis was that the “extra” citrate, that is, that added to food and consumed by the mice, would act on the hepatic synthesis of fatty acids and cholesterol.
Furthermore, it would have a correlation with the increase in overweight worldwide. There is already a statistical correlation between the increase in industrial food production, citrate consumption and the increase in population weight.
Early results showed that increased citrate consumption leads to a low-grade systemic inflammatory process in mice.
Initially, white adipose tissues were identified as the main responsible for this inflammatory process.
Later, it was seen that other tissues and organs, such as the liver, skeletal muscles and brown adipose tissue, are also compromised.
As a consequence of this process, the mice developed systemic insulin resistance, that is, the initial process that leads to type 2 diabetes mellitus.
Interestingly, all this happens without weight gain or even an increase in the mice’s adipose mass.
Furthermore, in the animals’ livers, there was an increase in fat deposits, an initial process of hepatic steatosis.
On the other hand, a very curious fact is that when mice consume an obesogenic diet (which leads to obesity), enriched with citrate, they do not develop obesity.
Intriguingly, another study shows that, even maintaining the same weight as the control group (which ate a standard balanced diet), these mice develop insulin resistance (pre-diabetes) and hepatic steatosis, in addition to other symptoms compatible with steatotic liver disease associated with metabolic dysfunction.
The entire phenomenon has not yet been understood. It is necessary to understand how citrate prevents weight gain in mice.
Ongoing studies show that this increased citrate consumption also leads to weight loss in obese mice, however, without reversing the health problems associated with obesity.
Apparently, the effects of citrate involve the physiology of the intestine and the modulation of the intestinal microbiota.
In another study by the study group, it was identified that increased citrate consumption leads to a condition similar to colitis, with an increase in intestinal permeability and a severe change in the composition of the microbiota.
Studies are ongoing. There are still many doubts about the effects of citrate consumed in excess of processed and ultra-processed foods on health.
However, there is certainty that it is not inert. The work, as well as that of other research groups around the world, shows that food additives affect our health and may play a relevant role in increasing the incidence of various diseases.
He has a PhD in biophysics and is a full professor at UFRJ (Federal University of Rio de Janeiro).
This text was originally by The Conversation on May 22, 2026. The content is free for republication, the source is cited, and has been adapted to the Poder360.
