Novel Perspective on the Regulation of Offspring Food Allergy by Maternal Diet and Nutrients.

There has been a dramatic surge in the prevalence of food allergy (FA) that cannot be explained solely by genetics, identifying mechanisms of sensitization that are driven by environmental factors has become increasingly important. Diet, gut microbiota, and their metabolites have been shown to play an important role in the development of FA. In this review, we discuss the latest epidemiological evidence on the impact of two major dietary patterns and key nutrients in early life on the risk of offspring developing FA. The Western diet typically includes high sugar and high fat, which may affect the immune system of offspring and increase susceptibility to FA. In contrast, the Mediterranean diet is rich in fiber, which may reduce the risk of FA in offspring. Furthermore, we explore the potential mechanisms by which maternal dietary nutrients during a window of opportunity (pregnancy, birth, and lactation) influences the susceptibility of offspring to FA through multi-interface crosstalk. Finally, we discuss the limitations and gaps in the available evidence regarding the relationship between maternal dietary nutrients and the risk of FA in offspring. This review provides novel perspective on the regulation of offspring FA by maternal diet and nutrients.

Skin-centered strategies in food allergy prevention.

While the early introduction of food allergens in the infant diet has been shown to be effective at preventing the development of food allergy (FA), its implementation in real life has been associated with various challenges. Interventions aimed at correcting skin barrier dysfunction have been explored in recent decades as a distinct or complementary mean to prevent allergic sensitization through the skin and subsequent development of FA. Studies assessing the application of emollient from birth have yielded conflicting results, and meta-analyses have demonstrated either no effect or only a slight positive effect on FA prevention. However, a careful review of the clinical trials reveals that different emollients were used, which may have explained some of the discrepancies between study results. Emollient application protocols also varied widely between studies. While firm conclusions cannot be drawn with regard to their overall efficacy at preventing FA, the available data provide valuable insight into the characteristics that could be associated with a more effective intervention. Namely, successful trials tended to use emollients with an acidic pH of 5.5, applied over the entire body, and combined with topical corticosteroids in affected areas. Consensus on the optimal strategy to restore skin barrier function could help improve the homogeneity and clinical relevance of future trials on this topic. In the meantime, clinicians should avoid products associated with worse outcomes.

Food Allergy Risk: A Comprehensive Review of Maternal Interventions for Food Allergy Prevention.

Food allergy represents a global health problem impacting patients' and caregivers' quality of life and contributing to increased healthcare costs. Efforts to identify preventive measures starting from pregnancy have recently intensified. This review aims to provide an overview of the role of maternal factors in food allergy prevention. Several studies indicate that avoiding food allergens during pregnancy does not reduce the risk of developing food allergies. International guidelines unanimously discourage avoidance diets due to potential adverse effects on essential nutrient intake and overall health for both women and children. Research on probiotics and prebiotics during pregnancy as preventive measures is promising, though evidence remains limited. Consequently, guidelines lack specific recommendations for their use in preventing food allergies. Similarly, given the absence of conclusive evidence, it is not possible to formulate definitive conclusions on the supplementation of vitamins, omega-3 fatty acids (n-3 PUFAs), and other antioxidant substances. A combination of maternal interventions, breastfeeding, and early introduction of foods to infants can reduce the risk of food allergies in the child. Further studies are needed to clarify the interaction between genetics, immunological pathways, and environmental factors.

Conformation-Activity Mechanism of Alcalase Hydrolysis for Reducing In Vitro Allergenicity of Instant Soy Milk Powder.

Effective reduction of the allergenicity of instant soy milk powder (ISMP) is practically valuable for expanding its applications. This study optimized the enzymolysis technology of ISMP using single-factor experiments and response surface methodology, combined serological analysis, cellular immunological models, bioinformatics tools, and multiple spectroscopy techniques to investigate the effects of alcalase hydrolysis on allergenicity, spatial conformation, and linear epitopes of ISMP. Under the optimal process, special IgE and IgG1 binding abilities and allergenic activity to induce cell degranulation of alcalase-hydrolyzed ISMP were reduced by (64.72 ± 1.76)%, (56.79 ± 3.72)%, and (73.3 ± 1.19)%, respectively (P < 0.05). Moreover, the spatial conformation of instant soy milk powder hydrolysates (ISMPH) changed, including decreased surface hydrophobicity, a weaker peak of amide II band, lower contents of α-helix and ß-sheet, and an enhanced content of random coil. Furthermore, the linear epitopes of major soy allergens, 9 from glycinin and 13 from ß-conglycinin, could be directionally disrupted by alcalase hydrolysis. Overall, the structure-activity mechanism of alcalase hydrolysis to reduce ISMP allergenicity in vitro was preliminarily clarified. It provided a new research direction for the breakthrough in the desensitization of ISMP and a theoretical basis for revealing the potential mechanism of alcalase enzymolysis to reduce the allergenicity of ISMP.

Tolerance induction through early feeding to prevent food allergy in infants and children with sensitization against food allergens (TIFFANI): rationale, study design, and methods of a randomized controlled trial.

BACKGROUND: Children with sensitization against foods have to be orally food-challenged before eating these foods for the first time. However, the waiting time for an oral food challenge (OFC) in Germany is about 3-6 months. In contrast, there are hints that an early introduction of allergenic foods might be protective regarding the development of food allergy. The aim of this clinical trial is therefore to investigate, whether an introduction and regular consumption of small amounts of food allergens is safe and will result in an increase of tolerance in children with sensitization against food allergens with unknown clinical relevance. METHODS: In this randomized, placebo-controlled, double-blind, single-center trial, 138 children (8 months to 4 years of age) sensitized to the target allergen(s) hen's egg, cow's milk, peanuts, and/or hazelnuts with unknown clinical relevance will be randomized in a 1:1 ratio to either an active or a placebo group, daily receiving a rusk-like biscuit powder with or without the target allergen(s) for 3-6 months until an OFC will be performed in routine diagnostics. The primary endpoint is an IgE-mediated food allergy to the primary target allergen, after the interventional period. DISCUSSION: Children with sensitization against food allergens with unknown clinical relevance often have to avoid the corresponding foods for several months until an OFC is performed. Therefore, the "window of opportunity" for an early preventive introduction of allergenic foods might be missed. This trial will assess whether an introduction of small allergen amounts will favor tolerance development in these children. TRIAL REGISTRATION: German Clinical Trials Register DRKS00032769. Registered on 02 October 2023.

Redefining the Role of Nutrition in Infant Food Allergy Prevention: A Narrative Review.

Pediatric food allergy remains commonplace, despite the advancement in our understanding of risk factors and prevention modalities for the condition. Early allergen introduction, a dietary intervention, has been endorsed by professional societies globally as an effective primary preventive measure, yet awareness among medical professionals and parents is lacking. Alongside food allergen introduction, overall nutrition, such as diet diversity, also plays an important role in allergy prevention. To address both food allergen introduction and overall nutrition, dietitians play a pivotal role in the dissemination and education of current guidelines to caregivers. This review addresses the particular role of the dietitian in food allergy prevention consultations, providing up-to-date information on food allergies, their development and prevalence, risk factors, dietary factors and an overview of the current guidelines in the United States. This has not been addressed in any of the current food allergy or nutrition guidelines.

[Primary prevention of food allergy in children]. / Prévention primaire de l'allergie alimentaire de l'enfant.

Pediatricians and allergists have noted a recent increase in cases of food allergy and anaphylaxis to peanuts and nuts, affecting very young children with worrying consequences in terms of quality of life. Children suffering from persistent cow's milk protein allergies that do not heal spontaneously are at very high risk of a fatal accident. Based on the findings of these studies, recommendations for primary prevention are made.

Perspectives in precautionary allergen labelling of prepackaged foods after the FAO/WHO consultation.

PURPOSE OF REVIEW: The purpose of this review is to provide an overview of the perspectives regarding precautionary allergen labelling (PAL) of prepackaged foods following the consultation conducted by the Food and Agriculture Organization (FAO) and the WHO. RECENT FINDINGS: The FAO/WHO consultation provided a comprehensive assessment of the current status and practices of PAL implementation worldwide. One of the key findings highlighted by the Expert Committee was the need for improvement in existing PAL systems. It was noted that many countries lacked uniformity in PAL practices, leading to inconsistencies in labelling and potentially misleading information for consumers. Furthermore, the consultation emphasized the importance of PAL being risk-based, taking into account both the amount and frequency of unintended allergen presence (UAP) in food products. SUMMARY: The FAO/WHO consultation shed light on various perspectives and challenges associated with PAL of prepackaged foods. Key findings emphasized the need for improvement in existing PAL systems, including the adoption of a risk-based approach, standardized regulations, and enhanced transparency. Moving forward, collaborative efforts between regulatory agencies, food manufacturers, and consumer advocacy groups will be essential in developing effective PAL strategies that prioritize consumer safety and well being.

Prenatal and postnatal exposure to antibiotics and risk of food allergy in the offspring: A nationwide birth cohort study in South Korea.

BACKGROUND: There are only preliminary studies examining the associations of postnatal antibiotic exposure with food allergy in childhood, and the effect of antibiotic exposure in utero has not been resolved. Thus, we aimed to investigate the effect of prenatal and postnatal antibiotic exposure on the risk of food allergy in childhood. METHODS: Using the nationwide birth cohort in South Korea, all 3,163,206 infants (pairing mother; n = 2,322,735) born in South Korea between 2010 and 2017 were included in the analysis. The primary outcome was the diagnosis of food allergy, and the observation period was between January 1, 2009, and December 31, 2020. We implemented four different designs for the study, which consisted of a full unmatched cohort, 1:1 propensity-matched cohort, sibling comparison cohort, and health screening cohort along with multiple subgroup analyses. RESULTS: During the follow-up period (median 6.92 years [IQR, 4.72-9.00]) of the 3,161,858 infants (52.6% male) in the birth cohort, 29,973 (1.9%) were diagnosed with food allergies. After a 1:1 propensity score matching, the use of antibiotics increased the risk of overall food allergy (prenatal [HR, 1.05; 95% CI, 1.04-1.09] and postnatal [HR, 1.05; 95% CI, 1.01-1.10] periods). The association was more significantly accentuated when antibiotic exposure was used in the short term, and the children were born preterm or with low birthweight; however, a trimester-specific effect was not observed. We observed more pronounced risks of food allergy in the health screening cohort (prenatal, 17%; postnatal, 15%), thus addressing the adverse effects of critical factors including maternal BMI, smoking status, and type of infant feeding. Similar trends were observed across all four differnt cohorts. CONCLUSION: This study reported a moderate association between early-life antibiotic use and subsequent food allergy during childhood throughout four different designs of analyses. This study suggests that clinicians need to consider the risks and benefits of antibiotics when administering antibiotics to individuals in the prenatal and postnatal periods.

Regular consumption following early introduction of allergenic foods and aggressive treatment of eczema are necessary for preventing the development of food allergy in children.

PURPOSE OF REVIEW: Over the past two decades, food allergy prevention strategies have shifted from 'delayed introduction' to 'no delayed introduction' to 'early introduction' of allergenic foods. This article reviews important research in this field published in the early 2020s to support future strategies for food allergy prevention. RECENT FINDINGS: Recent randomized controlled trials (RCTs), systematic reviews, meta-analyses, and real-world studies have reported that early allergenic food introduction, especially peanut and egg, are effective for preventing food allergies. However, there are also reports that food-induced anaphylaxis admission rates in infants are increasing. SUMMARY: Early allergenic food introduction by itself is not sufficient to prevent the development of food allergies. Recent RCTs (SPADE study and COMEET study) have demonstrated that continued regular cow's milk consumption after early introduction is important for preventing the onset of cow's milk allergy. Furthermore, an RCT (PACI study) reported that early and aggressive anti-inflammatory topical therapy for eczema can contribute to the prevention of egg allergy by suppressing percutaneous sensitization. Food allergies may be prevented through a combination of early food introduction, regular consumption, and active eczema treatment. Further research is needed to develop well tolerated, effective, and practical strategies to prevent food allergies.

Environmental Interventions for Preventing Atopic Diseases.

PURPOSE OF REVIEW: In this review, we detail the exposome (consisting of environmental factors such as diet, microbial colonization, allergens, pollutants, and stressors), mechanistic and clinical research supporting its influence on atopic disease, and potentiation from climate change. We highlight contemporary environmental interventions and available evidence substantiating their roles in atopic disease prevention, from observational cohorts to randomized controlled trials, when available. RECENT FINDINGS: Early introduction to allergenic foods is an effective primary prevention strategy to reduce food allergy. Diverse dietary intake also appears to be a promising strategy for allergic disease prevention, but additional study is necessary. Air pollution and tobacco smoke are highly associated with allergic disease, among other medical comorbidities, paving the way for campaigns and legislation to reduce these exposures. There is no clear evidence that oral vitamin D supplementation, prebiotic or probiotic supplementation, daily emollient application, and antiviral prophylaxis are effective in preventing atopic disease, but these interventions require further study. While some environmental interventions have a well-defined role in the prevention of atopic disease, additional study of many remaining interventions is necessary to enhance our understanding of their role in disease prevention. Alignment of research findings from randomized controlled trials with public policy is essential to develop meaningful public health outcomes and prevent allergic disease on the population level.

Relationship between perioperative anaphylaxis and history of allergies or allergic diseases: A systematic review and meta-analysis with meta-regression.

STUDY OBJECTIVE: We conducted this meta-analysis to summarize the available evidence and evaluate the relationship between a history of allergies/allergic diseases and perioperative anaphylaxis to offer preventive decision support. DESIGN: Systematic review and meta-analysis of observational studies. SETTING: We searched the MEDLINE (OVID), EMBASE, and the Cochrane Central Register of Controlled Trials databases for observational studies. Two investigators independently performed the search, screened the articles, and collected the study details. MEASUREMENTS: Several databases were systematically searched to evaluate the relationship between a history of allergies/allergic diseases and perioperative anaphylaxis using subgroup analysis, sensitivity analysis and meta-regression. MAIN RESULTS: A total of 19 studies involving 672 anaphylaxis episodes, 5608 immune-mediated reactions, and 1126 severe episodes met the eligibility criteria and were included in this meta-analysis. Drug allergies, food allergies, a history of allergies, and atopy increased the incidence of perioperative anaphylaxis (Drug allergies, odds ratio [OR] 3.54, 95% confidence interval [CI] 1.07-11.69; Food allergies, OR 2.29, 95% CI 1.23-4.26; A history of allergies, OR 4.86, 95% CI 3.65-6.49; Atopy, OR 3.58, 95% CI 1.47-8.71), but not the presence of immune-mediated reactions and the severity of perioperative anaphylaxis. CONCLUSIONS: Patients with previous drug allergies, food allergies, a history of allergies, or atopy are more likely to develop anaphylaxis during the perioperative period. Additional studies should be carried out to determine whether a history of allergies/allergic diseases is a major factor for perioperative anaphylaxis when confounders are controlled.

The pathogenesis of food allergy and protection offered by dietary compounds from the perspective of epigenetics.

Food allergy is a global food safety concern, with an increasing prevalence in recent decades. However, the immunological and cellular mechanisms involved in allergic reactions remain incompletely understood, which impedes the development of effective prevention and treatment strategies. Current evidence supports those epigenetic modifications regulate the activation of immune cells, and their dysregulation can contribute to the development of food allergies. Patients with food allergy show epigenetic alterations that lead to the onset, duration and recovery of allergic disease. Moreover, many preclinical studies have shown that certain dietary components exert nutriepigenetic effects in changing the course of food allergies. In this review, we provide an up-to-date overview of DNA methylation, noncoding RNA and histone modification, with a focus on their connections to food allergies. Following this, we discuss the epigenetic mechanisms that regulate the activation and differentiation of innate and adapted immune cell in the context of food allergies. Subsequently, this study specifically focuses on the multidimensional epigenetic effects of dietary components in modulating the immune response, which holds promise for preventing food allergies in the future.

Probiotics in Infancy and Childhood for Food Allergy Prevention and Treatment.

Food allergy represents a failure of oral tolerance mechanisms to dietary antigens. Over the past few years, food allergies have become a growing public health problem worldwide. Gut microbiota is believed to have a significant impact on oral tolerance to food antigens and in initiation and maintenance of food allergies. Therefore, probiotics have also been proposed in this field as a possible strategy for modulating both the gut microbiota and the immune system. In recent years, results from preclinical and clinical studies suggest a promising role for probiotics in food allergy prevention and treatment. However, future studies are needed to better understand the mechanisms of action of probiotics in food allergies and to design comparable study protocols using specific probiotic strains, defined doses and exposure times, and longer follow-up periods.

Precautionary Allergen Labeling: Avoidance for All?

PURPOSE OF REVIEW: Precautionary allergen labeling (PAL) suggests the risk of unintended allergen presence (UAP) in food but is unregulated in most countries and inconsistently applied by food manufacturers. This review evaluates the current use of PAL, its relevance to allergic consumers, and weighs possible advantages and disadvantages of avoiding products with PAL. RECENT FINDINGS: In most countries, manufacturers are free to decide whether, when, and how to apply PAL resulting in inconsistencies and consumer confusion. Patients with food allergy often interpret PAL incorrectly and without guidance from their health care providers. Health care providers are also prone to misinterpreting PAL, indicating a need for better education. Consumers desire guidance on whether to avoid products with PAL or not. Until further regulatory guidance is available, shared decision-making between patient and provider is required to offer individualized, rather than one-size-fits-all, approaches to PAL.