Halvah

Cross-reactivity

Case notes

On a label, halvah reads like a dessert, not an allergen. It is sesame-derived, but the ingredient statement may simply say halvah — or one of its spelling variants, halva or halwa — with no mention of sesame anywhere in the line. "Sesame candy" is clearer, though it often appears only on some packages of the same product. For a parent scanning a bake-sale table or a bulk-bin sticker, one of those spellings can slip past while the others register instantly.

Halvah sits in the 2S albumins family, the seed and nut storage-protein group associated with seeds allergy. That family matters for label reading because its members show up under many different names: the same protein class covers walnut (Jug r 1), cashew (Ana o 3), hazelnut (Cor a 14), and peanut (Ara h 2/6/7). Documented cross-reactivity within the group is uneven — moderate between peanut and walnut or cashew, weaker between peanut and hazelnut, with roughly 25 to 50 percent of peanut-allergic people reacting to tree nuts, and cashew-pistachio overlap noted as very strong at around 90 percent.

Practically, that means adding all three spellings to whatever list you carry, and remembering that sesame appears elsewhere under names like tahini, benne, gomasio, or sesamol. Reactions attributed to this family range from contact dermatitis and respiratory symptoms to anaphylaxis in severe cases, which is why the name on the package is worth pausing over rather than skimming past.