# 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  
3.1 Immunomodulatory Role of Plant Protein Sources, Lipid Profiles, and Fermentation Strategies in the Management of Allergic Symptoms  
The clinical relevance of macronutrient quality, protein source, and fermentation in individuals with established allergic disease is supported by data summarized in Table 5, which details the impact of plant-derived fats, proteins, and fermentation-derived peptides on symptom modulation, and in Table 6, which focuses on the preventive potential of processing strategies--such as enzymatic hydrolysis and microbial fermentation--in reducing the allergenicity of soy, legumes, and nuts. Importantly, in sensitized individuals, the allergenicity of soy, legumes, and nuts appears to play a greater role in the modulation of allergic symptoms than the overall macronutrient profile alone. Together, these findings emphasize that targeted processing and careful dietary management may help both prevent allergic sensitization in at-risk populations and attenuate clinical manifestations in those with established allergies. Narrative reviews [4; 5; 21; 22] have highlighted that certain plant proteins--especially from soy, nuts, and cereals--retain conformational and linear IgE-binding epitopes due to their structural resistance to digestion. This biochemical stability enhances their allergenic potential, particularly in the presence of lipid transfer proteins (LTPs) and Bet v 1 homologs that act as cross-reactive domains. In vitro assays across multiple studies have shown that such proteins can activate basophils and mast cells after simulated digestion, supporting their role in food-related allergic exacerbations. However, these same reviews also emphasize that targeted enzymatic processing and microbial fermentation may substantially reduce allergenicity. Enzymatic hydrolysis has consistently been shown to reduce IgE epitope availability and mast cell activation in simulated intestinal environments. Importantly, these processes may generate bioactive peptides that modulate immune responses, reduce epithelial reactivity, and support mucosal resilience. These mechanistic insights are reinforced by experimental findings. In a controlled in vitro and ex vivo analysis, [PERSON] and colleagues [23] assessed the effects of soy protein treatment via transglutaminase and lactic acid fermentation in a cohort of 36 samples, showing that this combined strategy reduced \(\beta\)-sheet structural integrity and significantly diminished IgE-binding capacity. Similarly, [PERSON] and colleagues [24] in a laboratory-based evaluation of soymilk fermented with _Enterococcus faecalis_, demonstrated a marked reduction in immunoreactivity to \(\beta\)-congplycinin and glycinin, confirming that peptide remodeling through fermentation can mitigate allergenic properties in plant proteins. The lipid composition of the diet is another critical factor in allergic inflammation. [PERSON] and colleagues [4] reported that high intakes of omega-6 fatty acids, typical of Westernized plant-based diets rich in refined seed oils, may favor Th2 polarization through elevated IL-4 and IL-13 production. Conversely, [PERSON] and colleagues [5] underscored the anti-inflammatory and barrier-protective effects of alpha-linolenic acid (ALA)-rich foods--such as walnuts, flaxseed, and chia--based on data from experimental animal models. These foods have been associated with increased Treg cell activation and downregulation of allergic cytokines, even when marine omega-3 fatty acid conversion is limited. Taken together, these results suggest that the symptom-modulating potential of plant-based diets in allergic individuals is tightly linked not merely to the exclusion of animal products but to a composite of factors: the structural quality and processing of plant proteins, the omega-6/omega-3 fatty acid ratio, and the use of traditional fermentation strategies.