Macadamia nut

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

Yes — macadamia nut is high in salicylate. Macadamias are high in salicylates despite their mild taste — the flavour gives no clue to the load, which is a recurring trap with this intolerance.

Macadamia nut contains moderate levels of histamine. Macadamias have the most saturated fat of the common nuts, which makes them the slowest to go rancid and the most forgiving in a warm cupboard. Neither fact moves them on this axis, because rancidity is oxidation and not amine formation. They are here as part of the nut group in the elimination lists and on no measurement of their own - which is the honest reason, and a thinner one than the level suggests. That is not quite the whole story any more: Yilmaz measured serotonin in twelve nuts and roasted macadamias came out lowest of all of them, 0.03 µg/g.

Macadamia nut contains moderate levels of nickel. Macadamia is among the gentler tree nuts on this axis - it is very high in fat, and fat carries almost no metal. What nickel there is sits in the solid fraction.

Macadamia nut contains only low levels of tyramine. Macadamia carries serotonin and related amines - nuts have been assayed for those specifically - but little tyramine. Dry seeds do not ferment, and it is fermentation that makes tyramine. Amounts vary by brand and recipe, so always check the label of the exact product.