Recently, we have had the pleasure of reading an article by Klimczak et al. [1], published in the Polish Journal of Allergology, which focused on the link between food allergy and gut microbiota. Delving into this topic, we encountered several review articles that addressed how this became a growing problem over the past decades, particularly in developing countries. We have observed an increase in prevalence of food allergy in infants and adults.

The aetiology of food allergy is multifactorial, involving genetics, environmental and immunological factors, but the newest studies highlight the potential role of imbalance of gut microbiota, known as dysbiosis [2]. Factors such as birth methods, breastfeeding, antibiotic use, vaccinations and exposure to pathogens, non-steroidal anti-inflammatory drugs, the hygiene hypothesis have the potential to influence the diversity of the gut microbiota [3–6]. The gut microbiota plays an essential role in maintaining the integrity of the intestinal barrier and modulates the inflammatory microenvironment within the intestine. Dysbiosis refers to imbalance or disruption of the gut microbiota, which can compromise the integrity of the gut barrier, allowing allergens, such as proteins, toxins and microbial by-products to cross the intestinal lining. Once these molecules pass through, they interact with gut-associated lymphoid tissue (GALT), potentially triggering immune response, which can lead to allergic reactions. Moreover, studies have shown that people with food allergy have different gut microbiota profiles than non-allergic individuals [1, 2, 7].

Preclinical and clinical studies emphasise the potential of probiotics, prebiotics and postbiotics in the prevention and treatment of food allergy through strengthening the gut barrier function and promoting restoration of healthy gut microbiota [1, 7]. Fecal microbiota transplantation (FMT) is a straightforward therapy that manipulates the human gastrointestinal microbiota and now is being explored as a promising therapeutic strategy to prevent food allergy. Further research of FMT may open new avenues for treating conditions with an increasing prevalence and social impact [1, 2, 7, 8].

This letter was written due to the increasing prevalence of food allergy. Further research is essential to improve our understanding of food allergy pathogenesis and to develop effective strategies for treatment and potential disease modification.