The metabolic products of Bifidobacterium may prevent allergies and asthma in children

2026-01-23

Researchers from the Technical University of Denmark have obtained a patent for a method that utilizes the metabolic products of bifidobacteria to reduce the risk of allergies and asthma in children. They believe that this discovery is expected to have a significant impact on the prevention of these chronic diseases, as these diseases are among the most common in children.

Project leader Susanne Brix Pedersen (professor of bioengineering) said: "The key breakthrough is that we have now identified a specific mechanism that can inhibit the development of allergic reactions in the immune system during infancy."

"If we can translate this knowledge into prevention strategies - for example, through probiotic supplements or infant formula containing probiotics - this will be a major advancement in the fight against allergies and asthma, which currently affect millions of children worldwide."

This study, published in Nature Microbiology, shows that the infant gut colonized by a specific bifidobacterium population produces 4-hydroxyphenylacetic acid lactate (4-OH-PLA), which reduces the production of antibody immunoglobulin E (IgE) - a key factor in triggering allergic reactions, like an "alarm system".

Boosting immunity through supplementation

The researchers observed 147 children from birth to age five and found that infants with a large bifidobacteria population in their intestines benefited from the metabolites. 4-OH-PLA was found to suppress the immune system’s overreaction to allergens.

Metabolites produced by specific bifidobacteria in the infant gut can dampen immune responses linked to allergies and asthma.Vaginal birth and breastfeeding were associated with increased bifidobacterial populations. Separate research found that bifidobacteria dominate breast milk, shaping infant gut development, immunity, and metabolism.

Surprisingly, children born through natural delivery are 14 times more likely to acquire bifidobacteria from their mothers than those born through cesarean section. Moreover, exclusive breastfeeding and early contact with other children also contribute to an increase in the number of these bifidobacteria in the intestines. This was stated by Rasmus Kaaja Deli, an expert in systems immunology at the Department of Bioengineering.

“This means that natural mechanisms help to prevent the development of these diseases. However, our lifestyle has contributed to these bifidobacteria becoming much rarer, and it is therefore also important to look at other preventive measures that can help infants who are not colonized with them.”

Recent studies have also found that supplementing with probiotics can help restore the intestinal microbiota of infants who are exclusively breastfed. In high-resource areas, the number of beneficial gut bacteria (especially infant bifidobacteria) in these infants is decreasing.

Furthermore, Perspecina Biosciences has discovered that 76% of American infants' intestinal microbiota puts them at risk of developing allergies, asthma, eczema, and dermatitis, as this is caused by the lack of bifidobacteria.

The researchers suggest that preventative strategies could include adding 4-OH-PLA or probiotic bacteria to dietary supplements or enriched formulas. This would create opportunities to improve infant health as the immune system is developing during the first months of life.

Currently, trials are underway at the Danish Aarhus University Hospital, where success could guide a new preventive strategy for children within a few years, with a “revolutionary” impact on their health.

Research details

Researchers analyzed stool samples from infants from three large birth cohorts in Sweden, Germany, and Australia.

Using genetic analysis and small-molecule studies, they mapped bacterial composition and metabolite levels. IgE antibodies against food and airborne allergens were measured through blood samples.

The researchers explained that when the human body comes into contact with allergens, IgE antibodies are produced, which activate immune cells and trigger allergic symptoms. These antibodies bind to the allergens, so the higher the IgE level, the greater the risk of allergy.

Furthermore, laboratory tests have shown that 4-OH-PLA can reduce the production of IgE by 60%, without affecting other antibodies.

The researchers also tested this mechanism in an experiment using human immune cells and found that 4-OH-PLA can directly inhibit the production of IgE. This indicates that there is a biological connection between certain bifidobacteria and their metabolites and the healthy development of the immune system.