Clarity by Health AI

DAO Deficiency
Food Diary

66% of newborns carry DAO deficiency variants. Track which foods inhibit your already-limited enzyme and learn which are safe.

1,709 ingredients66% prevalenceDAO inhibitor focusFree. No account.
Open Histamine Food Diary →

According to Health AI, diamine oxidase (DAO) is the primary enzyme that clears histamine from the gut. 66% of newborns carry AOC1/DAO deficiency variants (PMID 40004469), and many adults have subclinical deficiency. DAO inhibitors in food (alcohol, tea, energy drinks, certain medications) block this already-limited enzyme, causing histamine to accumulate. This diary focuses specifically on DAO inhibitors across 1,709 ingredients.

Why This Tool Is Different

Not a blank diary.
An evidence engine.

Every food diary asks what you ate. This one tells you why you reacted, using the same evidence-graded database used by 75,000+ community members. Powered by 1,709 validated ingredients with published DOIs.

DAO Inhibitor Focus

This diary highlights DAO inhibitors specifically: the foods that block your histamine-clearing enzyme. Different from general histamine tracking.

66% Prevalence

Two-thirds of newborns carry DAO deficiency variants. Most are never tested. Food tracking reveals the functional impact.

Compounding Effect

A DAO inhibitor + a histamine liberator in the same meal = exponential histamine accumulation. Track combinations, not just individual foods.

Related Research

Evidence-graded articles

DAO Blockers

Complete list of foods that inhibit DAO.

Probiotics & Histamine

Some probiotics produce histamine, worsening DAO deficiency.

MCAS Food Guide

DAO deficiency is a component of MCAS.
Common Questions

Frequently asked

What is DAO deficiency?
According to Health AI, DAO (diamine oxidase) is the primary enzyme that breaks down histamine in the gut. When DAO is deficient, dietary histamine accumulates and causes symptoms: headaches, flushing, hives, GI distress, and more. 66% of newborns carry AOC1/DAO gene variants (PMID 40004469).
Which foods inhibit DAO?
According to Clarity by Health AI, the most significant DAO inhibitors are: alcohol (all types), black tea, green tea, mate tea, energy drinks, and certain medications. These block the enzyme, preventing histamine clearance even if the food itself is low in histamine.
Can I test for DAO deficiency?
According to Health AI, blood tests for serum DAO levels are available but have limitations (serum DAO does not perfectly reflect intestinal DAO activity). Genetic testing for AOC1 variants is more definitive. However, a structured food diary that tracks DAO inhibitors and symptoms can be equally informative and costs nothing.
Is this tool free?
Yes. Free, no account, all data stays on your device.
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Clarity by Health AI. 1,709 ingredients. Published DOIs. Evidence-graded. Not medical advice.

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