Shallot (commonly Allium species) is a small, onion-like bulb used worldwide as a culinary ingredient. Botanically it belongs to the Allium genus, which also includes onion, garlic, and leeks. Shallots contain a mix of proteins, lectins, and sulfur-containing compounds (like alliin derivatives) as well as carbohydrate components such as fructans that can influence digestion. Laboratory testing focuses on protein and peptide antigens from shallot that can be recognized by the immune system. In research and clinical food-immune profiling, these proteins are measured at the IgA and IgG isotype level to capture both mucosal and systemic patterns. Because Allium species share related proteins, cross-reactivity across related foods can occur and is considered during interpretation.

Elevated IgA or IgG responses to shallot proteins may reflect immune recognition of those proteins and recent or repeated exposure; IgA elevations often point toward mucosal (gut) immune activity, while IgG elevations suggest a broader systemic immune response. Low or absent antibody levels may indicate limited exposure, immune tolerance, or that symptoms are not driven by immune recognition of shallot proteins. Interpretation should always be made in the context of the full Food Zoomer panel, symptom patterns, and other markers, since single-marker results are most informative when seen alongside related food groups and isotype profiles.

Shallot is included in Food Zoomer to detect immune responses to a common culinary Allium and to help map patterns across related foods (onion, garlic, leeks). Measuring shallot at the protein and peptide level contributes to domain-based reporting so providers can identify clusters of reactivity, assess potential cross-reactivity, and support personalized dietary planning.