Diamine Oxidase
Diamine oxidase (DAO) is an enzyme that breaks down histamine, mainly in the gut. Supplements are often made from pig kidney extract.
An encouraging pilot, with no placebo comparison
Twenty-eight patients with suspected histamine intolerance used DAO before meals for four weeks. Symptoms improved, then returned after stopping. Without blinding or controls, enzyme effects cannot be separated from expectations. 1
Why the comparison group matters
A one-month trial randomized 100 people with episodic migraine and low measured DAO. Headache duration fell in the DAO group, but the difference between groups was not significant. Attack frequency and pain intensity improved similarly in both groups. This is preliminary evidence, not established migraine prevention. 2
How the guideline weighs the evidence
The 2021 German, Austrian and Swiss society guideline judged efficacy unproven and did not recommend DAO supplementation. It also considered serum DAO testing inconclusive for diagnosing reactions to ingested histamine. 3
The guideline found efficacy unproven for suspected food-histamine reactions. 3
Effects by health goal
Open an effect to see the studies behind its rating. Bars show the size of the effect; the letter grades the evidence.
Gut Health6 effects
No study is linked to this rating.
No study is linked to this rating.
No study is linked to this rating.
No study is linked to this rating.
No study is linked to this rating.
No study is linked to this rating.
Immune Support1 effect
No study is linked to this rating.
Sources
- Diamine oxidase supplementation improves symptoms in patients with histamine intolerance Food Science and Biotechnology, 2019
- Guideline on management of suspected adverse reactions to ingested histamine DGAKI, GPA, AeDA, SGAI and ÖGAI; Allergologie Select, 2021