🍕 Here's what harms your health, even without excess calories

The consumption of ultra-processed foods is associated with an increased risk of developing many chronic diseases. These effects are often considered to be linked to the excess calories associated with them. In an article published in Cell Metabolism, scientists show that effects on health and fertility can be observed independently of calories consumed.

The ultra-processed epidemic

In France, approximately 80% of products available in supermarkets are so-called "ultra-processed" foods. They are characterized by industrial preparation processes and the addition of at least one synthetic ingredient.

For several years, epidemiological studies have established a strong correlation between their consumption and the onset of chronic diseases such as obesity, diabetes, and certain cardiovascular conditions. However, these studies reveal a correlation and not a formal causation: they show a significant association without demonstrating that these foods are the direct cause of these pathologies.

Health and hormonal dysregulation

To date, only three clinical studies have evaluated the direct effect of consuming ultra-processed foods on health. They mainly focused on metabolism and showed that an ad libitum diet rich in ultra-processed products led to higher calorie consumption compared to a minimally processed diet. This overconsumption made it difficult to distinguish effects related to the nature of the foods from those related to excess calories.

In a study published in the journal Cell Metabolism, scientists provide new insights. About forty young men followed two successive diets: one rich in ultra-processed foods, the other based on minimally or non-processed products. Two subgroups were formed; one receiving both diets in moderate quantities, adequate for their age, weight, and physical activity level, the other receiving both diets with a 500 kcal per day calorie excess.

In each group, the calorie amount of the ultra-processed diet and that of the minimally processed diet was the same. This experimental protocol allowed for distinguishing the effect of calorie overconsumption from that of the diet itself.

The results are concerning: the ultra-processed diet, with identical calorie quantity and consumed in moderation, led to weight gain, increased body mass, as well as an increase in the LDL/HDL ratio, an indicator of cardiovascular risk. Some hormonal changes were also observed, such as a decrease in two hormones involved in metabolism and male fertility (respectively the GDF-15 hormone and FSH). Sperm quality also tended to deteriorate, with a decrease in the number of motile sperm.

The endocrine disruptor lead

The complexity of industrial processes, the addition of additives, and the multiplication of preparation steps for ultra-processed foods mechanically increase the risk of contamination by industrial pollutants. These substances could play a role in the harmful effects of ultra-processed foods on health. In this study, measuring pollutants and pesticides in the blood and seminal fluid of participants revealed changes in blood lithium levels and a plasticizer (the phthalate cxMINP), an endocrine disruptor, which is found in higher quantities in the blood and seminal fluid after the ultra-processed diet.

This study highlights the role of ultra-processed food on male reproductive system health, possibly through the action of endocrine disruptors. It establishes that the amount of calories consumed is not the only factor responsible for these harmful effects and strengthens the idea that the ultra-processed nature of foods is a nutritional dimension in its own right.