10/22/2025
Your body actually uses 2 key genes to break down histamine
And they tell 2 very different stories…😳
Meet 🤝 DAO and HNMT
⚙️ DAO: The Gut Gatekeeper (more common)
DAO primarily works outside the cells,🍴 in the gut lining, placenta, and kidneys. Its job is to degrade extracellular histamine—especially the histamine from foods or microbial fermentation.
Symptoms of a sluggish DAO (dirty DAO):
• Bloating, food intolerances
• Skin itching, rashes, headaches
• Acid reflux or heartburn (often mistaken for excess acid)
• Unexplained irritable bowel issues
• Pregnancy nausea (DAO ramps up in 2nd trimester for a reason!)
Less dependent on methylation❗Can get “dirty” from gut inflammation, microbiome imbalance, or genetic variants.
🧠 HNMT: The Brain Regulator
HNMT handles🔬 intracellular histamine, primarily in the central nervous system. It requires methylation to function. Without it? Mental histamine builds.
Symptoms of poor HNMT activity (dirty HNMT):
• Restlessness, irritability
• Sleep issues, especially waking around 3–5am
• Headaches, vertigo
• Myoclonic twitches or mild tremors
• Mild respiratory symptoms: congestion
• If you have MTHFR (HNMT directly depends on methyl donors)
🙋♀️ Big Takeaway
Dirty MTHFR = Dirty HNMT = Chronic unease, sleep issues,
Dirty DAO = Dirty Gut = Food reactions, skin issues, pregnancy complications
Or both...
If you have symptoms in 🚩 both the gut and brain, your histamine imbalance may be bi-systemic. This means you likely need to support both DAO and HNMT pathways.
💬 Comment: “HISTA” to learn if your symptoms stem from DAO, HNMT, or both. We’ll explain why Histamine Nutrients🥇 is our top pick, get our guide, and learn how to optimize your protocol for deeper support.
Histamine intolerance supplements can support your body to have a healthy response to histamine.† Shop with Seeking Health® today.