Histamine Intolerance
Histamine intolerance is a condition where the body struggles to break down histamine efficiently, leading to a wide range of symptoms — many of them digestive.
Importantly, histamine intolerance is not an allergy but an imbalance between:
histamine intake
histamine release
histamine breakdown
Understanding this helps avoid unnecessary fear around food.
Why Histamine Becomes a Problem
Histamine intolerance is rarely caused by food alone.
It often reflects deeper changes in:
gut microbiome balance
enzyme activity (especially DAO)
intestinal permeability
immune activation
stress and nervous-system regulation
hormone fluctuations
SIBO or dysbiosis
chronic inflammation
Histamine is produced naturally in the body — the goal isn’t to eliminate it but to restore balance.
Common Symptoms
Digestive symptoms may include:
bloating
diarrhoea or urgency
abdominal pain
nausea after meals
reflux or burning discomfort
Whole-body symptoms can include:
flushing or warmth
headaches or migraines
hives or skin sensitivity
congestion
anxiety or restlessness
heart palpitations
menstrual pain or worsened PMS
Histamine intolerance often fluctuates — you may tolerate a food one week and react strongly the next.
This variability is a key sign.
Gut Conditions Linked to Histamine Intolerance
Many people with histamine intolerance have underlying digestive patterns such as:
SIBO (especially hydrogen or hydrogen sulphide types)
Dysbiosis
Leaky gut / intestinal permeability
Low DAO production due to mucosal irritation
Post-antibiotic microbial changes
Supporting the gut lining and restoring balance often improves histamine tolerance dramatically.
Stress & the Nervous System
Stress increases histamine release — particularly when the body is in fight-or-flight.
This is why:
symptoms worsen during overwhelm
anxiety increases during reactions
sensitivities fluctuate based on emotional load
Regulating the nervous system is a crucial part of rebuilding tolerance.
Nutrition & Lifestyle Support
Long-term improvement often involves:
reducing inflammation in the gut lining
supporting the microbiome (especially Bifido species)
improving digestive secretions
stabilising motility
supporting hormone balance
restoring DAO activity
temporarily reducing histamine load only when needed
gently reintroducing foods
The aim is not lifelong restriction — but restoring flexibility and resilience.
This Page in One Sentence
Histamine intolerance is a whole-body, gut–brain–immune pattern — not simply a food list — and it improves most when the root drivers are supported.