With the increasing prevalence of allergies, accurate identification of allergens is a major priority for allergists, scientists, the food industry, and food regulators. Knowledge of allergens is essential for risk assessment of novel genetically modified (GM) foods, and to develop recombinant proteins for the treatment and diagnosis of allergies. This Opinion Paper considers the lack of standardization for the clinical and scientific assessment of proteins before they are labelled as allergens. Food allergens are being reported and recorded in allergen databases, with minimal or in some cases apparently no published justification. IgE binding, rather than clinically relevant reactivity, is inappropriately used to confirm allergenicity. Using kiwifruit as an example, the lack of rigor in identifying allergenic proteins is considered.