Buttermilk

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

Buttermilk contains moderate levels of FODMAPs. Buttermilk is cultured, and the bacteria have worked on the lactose for longer than a yoghurt gets - which is why it sits a level lower. Traditional buttermilk, the liquid left after churning butter, is lower still than the cultured product sold under the same name.

Buttermilk contains moderate levels of lactose. Cultured buttermilk is fermented, so part of the lactose has already been eaten and it carries a little less than the milk it was made from.

Buttermilk contains moderate levels of histamine. Buttermilk is cultured, so bacteria have been at work — and wherever bacteria ferment a protein food, some histamine follows. Far below aged cheese, but above plain milk. Pasteurisation, starter culture, salt, pH and ripening time decide more than the name on the label.

Buttermilk contains only low levels of tyramine. Buttermilk is a short soured culture, hours rather than months. On this axis dairy splits in two, and the dividing line is ripening: aged cheese is one of the four foods a MAOI diet excludes outright, while fresh dairy is among the safest things on the shelf. The same milk becomes either one. Amounts vary by brand and recipe, so always check the label of the exact product.