Peanut

Peanut is notable for oxalates, histamine, nickel and salicylate. Clear on tyramine, sucrose, FODMAPs, lactose, oligosaccharides, sorbitol, fructose and gluten.

Yes — peanut is high in oxalates. Peanuts are a legume rather than a nut, and they sit high here anyway - the botany does not rescue them. What does help is calcium: oxalate and calcium bind to each other in the gut and leave together, so peanuts with a dairy or fortified food alongside are absorbed less than peanuts alone.

Peanut contains moderate levels of histamine. Peanuts are named with walnuts and cashews as liberators, and they carry a risk the other nuts do not: they are a legume, stored in bulk and prone to mould, and mould growth is what raises amines fastest in a stored crop. Fresh, dry and well kept is the whole instruction. The Swiss list, by contrast, rates “peanuts” 2 of 3 without giving it the L it reserves for liberators.

Peanut contains moderate levels of nickel. The peanut is a legume that grows underground, so it takes nickel up through the urease route like beans and lentils, and takes it from the soil it sits in. Filed with the nuts on every shelf, it belongs with the pulses here.

Peanut contains only low levels of salicylate. Peanut is low in salicylate, and notably lower than tree nuts - peanuts are a legume, not a nut, which is why they behave differently here. Amounts vary by brand and recipe, so always check the label of the exact product.