Cow’s milk and allergies in children — the culprit we don’t suspect?

Aim of the study: Cow's milk allergy (CMA) is one of the most common causes of food allergies (FA) in children. Studies have examined the use of immunotherapy for cow's milk protein allergy, with oral immunotherapy (OIT) being the most extensively researched. We conducted a comprehensive analysis of randomized controlled trials (RCTs) to explore the efficacy and safety of OIT for managing cow's milk allergy in children.

Results: Nineteen RCT articles (815 participants) were included. The meta-analysis indicated that oral immunotherapy significantly facilitated desensitization in children with cow's milk allergy (relative risk [RR] 2.51, 95% CI: 1.54-4.09, I²=84.4%). The tolerance threshold during oral food challenges (OFC) increased following oral immunotherapy, with a standard mean difference (SMD) of 3.58 (2.82-4.33). After oral immunotherapy, antibody titers of cow milk protein sIgE (SMD -0.42, 95% CI: -0.72 to -0.11, I²=28.8%) and casein sIgE (SMD -0.54, 95% CI: -0.97 to -0.11, I²=0%) decreased. The risk of adverse reactions with immunotherapy was not higher than that in the control group, with an RR of 2.05 (95% CI 0.96-4.37, I²=81.5%). Oral immunotherapy is associated with desensitization to CMA in children, without an increased risk of short-term adverse events, but late complications such as eosinophilic esophagitis require caution.

Aim of the study: Limited evidence indicates that baked milk (BM) intake accelerates cow's milk allergy (CMA) resolution or modulates immunity in BM-tolerant (BMT) and BM-allergic (BMA) phenotypes. This study evaluates the efficacy, safety, and immunological effects of introducing BM, focusing on regular intake in BMT and low-dose intake in BMA, and their impact on the development of tolerance.

Results: A total of 50 participants with confirmed CMA were included, of whom 32 were BMT and 18 BMA. Daily BM intake in the B2 group significantly enhanced tolerance to CM (77.2% vs 40% in C2, P < .05), with improved safety and marked reductions in SPT and sIgE markers. Reactivity thresholds increased 9-fold (0.9 g vs 0.05 g). No significant increase in tolerance was seen in the B1 group. Mild reactions at home occurred in 9.3%. Predictors of tolerance included young age (<24 months), BM consumption, absence of asthma, immunological markers (sIgE, SPT, and sIgG4/sIgE), and reduced BAT reactivity. Early BM introduction appears to support CMA resolution in BMT and may improve safety, particularly in young children. Regular BM consumption could contribute to better outcomes, while biomarkers offer valuable insights for personalized management.

Aim of the study: Interventions targeting the gut microbiota to treat food allergy (FA) have been receiving much attention. Although several studies have examined the effects of probiotics, few have verified the effects of prebiotic interventions on FA in humans.

Results: Kestose treatment significantly increased the threshold dose for milk protein and decreased milk- and casein-specific IgE levels in serum. In those treated with kestose, the abundance of Fusicatenibacter spp. significantly increased in the feces, and a significant inverse correlation was seen between the abundance of Fusicatenibacter spp. and milk- and casein-specific IgE levels. Kestose treatment induced some tolerance to milk protein through changes in gut microbiota composition in children with FA.

Aim of the study: Scoping review on IgE-mediated cow's milk allergy prevention.

Results: There is increasing literature supporting the role of early and ongoing cow's milk ingestion in the prevention of cow's milk allergy. Studies supporting a preventive role for early cow's milk ingestion suggest introducing cow's milk at a very early age (most within the first month of life), pointing to the possibility of a different sensitization mechanism than that for other common allergens. Gut colonization and the diversity and intensity of microbial exposure may play a role in inducing cow's milk tolerance. Vitamin D may also have a role in regulating these immune functions. Further research is needed on the role of early cow's milk ingestion in preventing cow's milk allergy, and questions remain. The amount needed to achieve tolerance is unclear. Studies in higher-risk populations are needed.

Aim of the study: To determine whether the timing and continuity of neonatal cow's milk formula (CMF) exposure influence the risk of IgE-mediated cow's milk protein allergy (CMPA).

Results: Among infants exposed to cow's milk formula within the first 72 h, discontinuation within 14 days was associated with higher odds of CMPA than continued exposure for ≥15 days (aOR: 8.07; 95% CI: 3.20-20.36; p < .001). In contrast, continuous exposure (≥15 days) was associated with substantially lower odds of CMPA, independent of delivery mode. It appears that sensitization is driven not by early exposure itself, but by brief and discontinuous exposure. These findings highlight a critical "window of vulnerability" in early life, suggesting that unnecessary short-term formula supplementation should be avoided, while continuous exposure—if initiated—may support the development of oral tolerance and may have immediate implications for neonatal feeding practices and allergy prevention strategies.