They warn that détox diets based on fiber juices can damage health

Fruits and vegetables are essential foods that should be included in the daily diet. In fact, the Spanish Society of Endocrinology and Nutrition (SEN)1 It recommends taking 5 rations of fruit and vegetables per day, although it points out that a piece of fruit is not the same, than a ration, and that we must “adjust the amount consumed of a certain fruit or vegetables to its caloric value” with the objective to avoid imbalances in the diet.

Many people, however, consider that feeding based on fruit and vegetable juices can be a healthy way to lose weight or compensate for days of food excesses, such as after the Christmas holidays or after a holiday at a hotel or a cruise with ‘ all inclusive’. It is what is popularly known as detox or purifying diet.

However, these types of initiatives without the supervision of a professional can have serious health consequences, according to researchers from the Northwestern University2 In a study that reveals that following a diet based solely on fruit and vegetable juices, even for only three days, can cause changes in intestinal and mouth bacteria linked to inflammation and cognitive deterioration. The results have been published in the Magazine Nutrients3.

Why do you have to prioritize fiber in the diet

These scientists studied three groups of healthy adults. One group consumed only juice, another took juice with comprehensive foods and a third one ingested only comprehensive plant foods. The researchers collected saliva, mouthwashes and stool samples before, during and after diets to analyze bacterial changes using genetic sequencing techniques.

The most significant increase in bacteria associated with inflammation and intestinal permeability was observed in the group that only took juice, while the group that consumed comprehensive foods of plant origin experienced more favorable microbial changes. The group that consumed juice more food had some bacterial changes, but less severe than the group that only consumed juice. These findings suggest that taking fiber juice can alter microbiome, which could have long -term health consequences.

“Most people think that taking juices is a healthy way to debug Feinberg Medicine of the Northwestern and Medical University of Northwestern Medicine, in a note published by the center. “Consuming large amounts of juice with little fiber can cause imbalances in microbiome that could have negative consequences, such as inflammation and reduction of intestinal health,” he adds.

In the juices a large part of the fiber that contains the entire fruits and vegetables and that feeds the beneficial bacteria that produce anti -inflammatory compounds such as the butyrate. Without fiber, sugar -love bacteria can multiply. And the high sugar content in the juice further feeds these harmful bacteria, which alters the intestinal and oral microbiome. The study also suggests that a reduced fiber intake can affect metabolism, immunity and even mental health.

“Consuming large amounts of juice with little fiber can cause imbalances in microbiome that could have negative consequences, such as inflammation and reduction of intestinal health”

Unlike the intestinal microbiota, which remained relatively stable, the oral microbiome showed drastic changes during the diet based solely on juices. The scientists found a reduction in the beneficial signature bacteria and an increase in proteobacteria, a bacterial group associated with inflammation.

“This highlights the speed with which food decisions can influence health -related bacterial populations,” Ring said. “Oral microbiome seems to be a quick barometer of the impact of the diet.” The findings underline the need for more research on how juices and other diets impact the microbiome, especially in children, who often take fruit juices as substitutes for the whole fruit.

“The nutritional composition of juice -based diets, specifically their levels of sugar and carbohydrates, plays a key role in the formation of microbial dynamics, both in the intestine, as in the oral cavity, and must be carefully considered,” he says The first author Maria Luisa Savo Sardaro, an associated researcher at the Amato Laboratory in the Department of Anthropology at Northwestern University and Professor of Food Microbiology at the San Raffaele University in Rome.

This study also highlights the importance of prioritizing fiber in dietary guidelines and food production. For now, says Ring, “if you love to make juices, consider liquefy in its place to maintain intact fiber, or combine juices with comprehensive foods to balance the impact on your microbiome.”