Histamine intolerance
Difficulty breaking down dietary histamine, usually through a deficiency of the DAO enzyme, causing varied symptoms often mistaken for an allergy.
Histamine intolerance results from an imbalance between the histamine you ingest or produce and your ability to break it down. The main enzyme, DAO (diamine oxidase), breaks histamine down in the gut. A DAO deficiency (genetic, acquired or caused by inhibition) leads to a build-up of histamine and symptoms.
A fresh angle (the chameleon “pseudo-allergy”): histamine intolerance is misleading because its symptoms mimic an allergy without being one (no IgE, no specific immune reaction). It is often called a “pseudo-allergy”. Symptoms are varied and bewildering: headaches/migraines, flushing, hives, nasal congestion, palpitations, digestive problems, sometimes anxiety.
Their dose-dependent nature (it depends on the total amount of histamine accumulated) explains why reactions are inconsistent: a food is tolerated one day but not another (depending on how full the “histamine bucket” is that day). This is the “overflowing bucket” concept.
The foods involved (two categories):
- High in histamine: mature cheeses, cured meats, fish (especially if poorly stored), fermented foods, wine, beer, tomato, spinach, aubergine, avocado, chocolate
- Histamine liberators (trigger the body to release histamine): strawberry, citrus fruit, shellfish, egg white, additives
DAO inhibitors: some factors block DAO and make the intolerance worse: alcohol (a major one), certain medicines and… gut dysbiosis. Restoring the gut can improve the situation.
The probiotic trap: a crucial point, some probiotic strains produce histamine (certain Lactobacillus) and can worsen the intolerance! You need to choose strains that do not produce histamine (or even break it down).
The approach: a low-histamine diet (temporary) to confirm, then reintroduction; identifying DAO inhibitors to avoid (alcohol, certain medicines); looking after the microbiome; sometimes DAO supplementation before meals. Ideally supervised, because the low-histamine diet is complex.