Reacción a "Reactions: study links emulsifier consumption by pregnant mice to health problems in offspring"

We have known for just over a decade that ultra-processed foods are linked to various diseases, the number of which is growing as scientific knowledge increases. However, there is very little information available that can establish cause-and-effect relationships between the consumption of these products and the development of diseases. Nor do we have enough information on the mechanisms involved.  

The NOVA classification is the most commonly used to define ultra-processed foods, specifically in the NOVA4 group. Among the characteristics of these products is the use of additives that promote their consumption, such as flavourings, colourings, flavour enhancers and emulsifiers, among others.  

In this study, researchers from IDIBAPS in Barcelona (Spain) found that mice whose mothers consumed emulsifiers showed an increased risk of metabolic, cognitive and psychological problems in their offspring, especially in males. The results indicate that maternal consumption of emulsifiers may disrupt the development of neural circuits in the offspring's hypothalamus, a region that regulates metabolism.  

The study is important because it contributes to our understanding of the components of ultra-processed foods that may contribute to their negative health effects. However, some caution should be exercised in interpreting it.  

Firstly, it is a study carried out in mice, so its conclusions cannot be extrapolated to humans. In other words, we cannot say that the consumption of emulsifiers by humans has the same consequences as shown in the study.  

Secondly, the emulsifiers were administered to the animals in drinking water, not in the form of ultra-processed feed.  

Thirdly, there are many types of emulsifiers, but the researchers only tested two of them: sodium carboxymethyl cellulose and polysorbate 80. It is possible that other 'more natural' emulsifiers, such as lecithin, guar gum or partial glycerides have different effects.  

Fourthly, the emulsifiers were added to the drinking water of the mice at 1 %, which is a rather high dose.  

As can be seen, this type of study has some limitations in terms of design. This is common in preclinical studies because the focus is on finding some observable effect to serve as a starting point for future research.  

On the other hand, it is necessary to underline that research on ultra-processed foods in humans is very complex for many reasons, one of which is ethical. Given that there is sufficient information linking the consumption of ultra-processed foods to human health, it may be considered unethical to administer a diet rich in ultra-processed foods to a group of people for a study. This is one of the reasons why there are so few clinical trials that have evaluated the effect of ultra-processed foods in humans.  

Therefore, although the link between ultra-processed foods and disease is known, science has not yet been able to demonstrate a clear cause-and-effect connection and detailed information on the mechanisms involved. This study in mice provides important information for understanding the specific components of these foods that may have adverse health effects. However, it should be viewed with caution due to methodological limitations.