# Sustainable Plant-Based Diets and Food Allergies: A Scoping Review Inspired by EAT-Lancet
## 3 Results
### Core Dietary Determinants of Allergy Prevention and Management Within Sustainable Eating Models
\begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline
**Author and Year** & **Level of Evidence (CEBM 2009)** & **Study Population and Design** & **Main Findings** \\ \hline \multirow{4}{*}{[PERSON] et al., 2019 [35]} & \multirow{4}{*}{Level 5} & Review of \(\sim\)50 studies on probiotics in allergy and autoimmunity; mainly preclinical and pediatric populations. & \multicolumn{1}{p{113.8 pt}}{} & \\ \cline{3-4}  & & Narrative review of & Dysbiosis linked to food allergies. \\ \cline{3-4}  & & \(>\)30 studies including RCTs and cohorts; pediatric food allergy focus. & Dietary/ probiotic modulation improves tolerance and symptom control. \(p\)-values not applicable. \\ \hline \multirow{4}{*}{[PERSON] \& [PERSON], 2019 [37]} & \multirow{4}{*}{Level 5} & Narrative review on microbiota-targeting dietary interventions; \(\sim\)30 allergy prevention trials. & \multicolumn{1}{p{113.8 pt}}{} & \\ \cline{3-4}  & & & \\ \hline \end{tabular}
\end{table} 
Table 9: _Cont._reduction in food allergy incidence among infants receiving probiotic supplementation. The observed benefits were associated with enhanced microbial diversity and increased production of short-chain fatty acids (SCFAs), supporting the role of microbial metabolites in early immune education. Many narrative reviews [4; 7; 19] converge in identifying SCFAs--primarily butyrate and acetate--as key mediators in the suppression of Th2 and Th17 responses. These SCFAs are generated through bacterial fermentation of dietary fibers like inulin, pectin, and resistant starch and contribute to epithelial barrier integrity, immunoglobulin A production, and Treg expansion. [PERSON] and colleagues [5] emphasized that fiber-enriched diets modulate mucosal inflammation by favoring beneficial microbial taxa, while [PERSON] and colleagues [19] noted reduced levels of _Faecalibacterium prausnitzii_ in allergic individuals--a marker of dysbiosis potentially reversible through diet. [PERSON] and [PERSON] [37], based on \(\sim\)30 preclinical and interventional studies, reported that early-life exposure to fermentable fiber or prebiotics alters microbial colonization patterns and reinforces tolerogenic responses. These findings were echoed by [PERSON] and colleagues [34], who detailed how microbial and nutritional programming during infancy is critical to allergy prevention. Collectively, these reviews support the integration of dietary fiber and probiotics into preventive frameworks, particularly during developmental windows of immune plasticity. From a mechanistic standpoint, [PERSON] and colleagues [20] provided insights into the pathways linking dysbiosis and allergic sensitization. They reported that gut microbial imbalance impairs immune education and barrier function, while targeted nutritional interventions (especially fibers and probiotics) restore immune equilibrium and oral tolerance. These molecular and immunological insights form the rationale behind microbiota-directed strategies in allergy prevention. In terms of clinical management of allergic patients, narrative and clinical reviews indicate a growing role for dietary modulation of the microbiome in symptom control. [PERSON] and colleagues [33] synthesized data from \(\sim\)35 studies, noting that probiotic strains such as Lactobacillus and Bifidobacterium can suppress IL-4 and IL-5, reduce histamine production, and increase Treg activity. [PERSON] and colleagues [35] reinforced this conclusion by showing increased IL-10 and mucosal integrity across preclinical and pediatric studies following probiotic administration. [PERSON] and colleagues [36], in their review of over 30 clinical trials and cohort studies, reported improved tolerance and reduced symptom burden in allergic children undergoing microbiota-targeted interventions. The beneficial effects were attributed to a reduction in IgE sensitization and the expansion of anti-inflammatory microbial taxa such as _Bifidobacterium longum_.