WHAT ARE ULTRA-PROCESSED FOODS AND HOW DO THEY AFFECT OUR HEALTH?

We have been consuming these foods for many years, but the term has only recently been on everyone's lips. In Spain, the consumption of ultra-processed foods (UP) has tripled between 1990 and 2010, going from 11% to 32% of the energy contribution of the diet. Among Spanish adults, the most consumed groups of UP were meat and processed meat (17%), pastries and sweets (14%), biscuits (9%), dairy products (9%), jam and cakes (7%) and ready-made meals (7%). Among children, the most common are sweets and cakes (32%), cereals (26%), dairy products (19%), ready-made meals and sauces (15%), processed meat (5%) and sugary drinks (4%).

But what has caused the general population to increase its consumption of UP?

PUs are widely consumed for their palatability, affordability and convenience. In other words, their intense flavour and texture stimulate appetite and pleasure, but they are not satiating and that makes us eat more. On the other hand, their lower cost and high availability make them more accessible than fresh and nutritious foods, especially for people with “busy lifestyles” since their preparation is simpler. Finally, their prominence and publicity in the environment make them more visible and attractive and influence consumer preferences and choices, especially among younger consumers.

Definition of ultra-processed

Now let's look at the term itself. Do we know exactly what it means for a food to be “ultra-processed”? Well, this term refers to the number of times that foods are processed to produce a final product and the number of ingredients it contains. In 2009, a team of researchers led by Carlos Monteiro published a classification of foods that took into account - although not exclusively - their degree of processing. Their idea was to find a common denominator for all those food products that had a clear unhealthy or undesirable profile. In other words, they looked for a pattern that would characterize what is known as junk food.

According to this classification called NOVA, which is the most used for the degree of processing of foods, UP are characterized by:

• Complexity of ingredients: they contain long lists of ingredients.
• Low presence of whole foods: PUs are foods that have been significantly altered and are far removed from their natural or original form.
• The high content of additives and artificial substances: such as colorants, flavorings, sweeteners, preservatives, among others.
• Low nutritional density: Despite being high in calories, they tend to be low in essential nutrients such as vitamins, minerals and fiber.
• Highly palatable and addictive: They are designed to be very tasty and encourage excessive consumption.

The term “ultra-processed” was therefore coined to describe foods that have gone through multiple industrial processes and contain refined ingredients and additives. And as we’ve said, these foods often have little nutritional value and are associated with higher saturated fat, added sugars, and sodium content. In addition, they are often made using processes and with ingredients that are uncommon and unreproducible in home kitchens, such as hydrogenated oils, modified starches, additives, etc.

The impact on health

The categorization of foods as PU has become relevant in the field of public health, since an association has been observed between excessive consumption of these foods and health problems, such as obesity, cardiovascular diseases and diabetes. This food category contains an infinite number of foods (carbonated drinks, breads and rolls, yogurts, ready meals, meat extracts, sauces, etc.) however there are products that by definition may not be included in this category and may still be unhealthy, and vice versa.

The consumption of UP, first of all, can lead to the displacement of a balanced diet that contains essential nutrients for our body present in foods such as fruits, vegetables, grains, legumes, seeds and lean meats. For example, if I decide to have cookies and a chocolate shake every day for a snack, I would be displacing the potential snack of a yogurt with fruit or a banana and a toast. The constant displacement of foods rich in macro and micro nutrients (e.g. fiber, proteins, healthy fats, vitamins, minerals, antioxidants) causes a deficiency of essential nutrients and causes damage to our body.

Many studies have shown that PUs are associated with weight gain, mental disorders, multi-cause mortality, hypertension, diabetes, sleep problems, tooth decay, metabolic syndrome, and other health problems . PUs can also affect the brain and its regulation of appetite, as well as the balance of bacteria living in the gut (gut microbiota). These effects are due to PUs causing inflammation, oxidative stress, metabolic dysfunction, and epigenetic changes.

What are these ingredients and how do they affect our health?

1. Sugar:

Sugar, a simple carbohydrate present in most PUs, contributes to weight gain, blood glucose imbalance, development of type 2 diabetes, elevation of “bad” cholesterol and blood pressure, as well as the risk of cardiovascular disease and gout. It also negatively affects dental health, promoting the appearance of cavities and enamel erosion.

To counteract the effects of sugar, some people turn to sweeteners as an alternative. However, the World Health Organization (WHO) advises against their use to control weight or reduce the risk of disease, as there is insufficient evidence of their benefits. In fact, some studies even suggest that sweeteners could alter the intestinal microbiome, hormonal response and insulin sensitivity, increasing the risk of type 2 diabetes and cardiovascular disease.

2. Trans Fats:

Trans fats, found in processed foods such as margarine and baked goods, also pose health risks. They have been associated with an increase in “bad” cholesterol, a decrease in “good” cholesterol, and an increased risk of cardiovascular disease, type 2 diabetes, inflammation, obesity, and cancer.

3. Newly formed contaminants:

Thermal processing of food, such as frying, baking or roasting, can generate newly formed contaminants such as acrylamide, furan, heterocyclic amines or dioxins. These compounds, classified as possible or probable human carcinogens, can have toxic effects on DNA, the nervous system, the liver, kidney or the endocrine system.

4. Additives and Chemicals:

The vast majority of UP contain additives as preservatives or to enhance sensory properties. Some of these components, such as monosodium glutamate, aspartame or sodium benzoate, have been linked to the development of neurodegenerative diseases, such as Alzheimer's or Parkinson's. These compounds can cause damage to the stomach and liver, as well as alter communication between the intestine, brain and liver.

For example, silver and titanium dioxide nanoparticles, widely used as preservatives and colorants, can modify intestinal permeability and cause inflammatory responses. These substances damage the intestinal microbiome and cause an imbalance between beneficial and harmful bacteria, called dysbiosis . When this imbalance occurs, the levels of anti-inflammatory molecules called short-chain fatty acids (SCFA) are reduced and intestinal permeability increases , allowing harmful particles and substances to pass into the bloodstream. The particles reach the brain and cause inflammation , which can cause neurological disorders. Along these lines, it has also been shown that Bisphenol A (BPA), a chemical compound present in most plastic packaging and utensils, can migrate to food and beverages, especially when the containers are heated or damaged. Its negative effects cover various areas of the body, causing an increased risk of cardiovascular disease by interfering with glucose metabolism, insulin and lipid regulation. It has also been observed to affect brain development and function, fertility and reproduction, increase the risk of prostate and breast cancer, and induce an inflammatory response.

It is important to maintain a balanced diet and not become obsessed with avoiding PUs. Even among foods that are not considered PUs, there are unhealthy options. Incorporating PUs occasionally, representing approximately 5% of the diet, does not usually have significant effects on health. However, in order to make informed decisions about food, it is essential to be able to read the ingredients on the labels and the nutritional values ​​of the products we buy. This knowledge is what gives us the power to consciously choose the foods we eat, thus contributing to maintaining a balanced and healthy lifestyle.

Written by Maria Caballero

Pharmaceutical