Histamine and amine intolerance occurs due to an accumulation of histamine or an inability to effectively break down histamine in the body. Histamine is a naturally occurring chemical substance which is produced by the body and some foods. Histamine plays an important role in the body and is involved in the immune system response, the digestive system, and the central nervous system. It can work as a neurotransmitter communicating important signals from the body to the brain. Histamine is also involved in the production of stomach acid and digestion.

When histamine is ingested from foods it can usually be detoxified by substances called amine oxidases, however if a person has low amine oxidase activity they are at risk of histamine toxicity.

The main enzyme responsible for the breakdown of ingested histamine is called Diamine oxidase (DAO). DAO is found mainly in the kidneys, thymus, and the placenta in pregnant women (which is why allergies often improve during pregnancy). When DAO is functioning efficiently ingested histamine is broken down within the digestive tract and removed before it can enter the body. When histamine levels inside the body become excessive, DAO, and another enzyme called histamine N-methyl transferase (HNMT) break down the excess. If DAO activity is impaired, histamine can accumulate to excess and may cause a number of adverse symptoms that mimic a hypersensitive or allergy type reaction.

Histamine can build up due to the ingestion of histamine-rich food or by food, drink or medications that either release histamine or inhibit the DAO enzyme.

Decreased DAO enzyme production and high histamine tends to be more common in people with the following: Methylation dysfunction, gut disorders such as celiac disease, leaky gut syndrome, inflammatory bowel disease, irritable bowel syndrome, dysbiosis and SIBO (small intestinal bacterial overgrowth).

DAO activity can also be inhibited by certain medications. Increased histamine may aggravate symptoms such as gastric stress, nausea, headaches, mood disorders, depression, sinus problems, skin rashes, eczema, rosacea, psoriasis, join inflammation, breathing difficulties, rapid heartbeat, rashes, itching, burning eyes, and flushing of the skin.

General guidelines:

1. Keep a food diary and monitor symptoms. This will give you a good idea of which foods you are most sensitive to.
2. Avoid canned food, particularly fish and meats
3. Avoid precooked and pre prepared ready meals, the older the food the more histamine it can produce.
4. Avoid fermented foods such as aged cheeses, cultured vegetables, alcohol, yeast products (yeast serves as a catalyst for histamine production)
5. Avoid food additives such as preservatives and azo dyes as these can mediate the release of histamine.
6. Where possible buy and eat fresh products.
7. Support gut health. Histamine intolerance often occurs when there is increased gut permeability or dysbiosis in the gut. Once gut health has improved histamine foods may be more easily tolerated.

High histamine and amine foods to reduce:

•  Aged, fermented, canned, cured and left over foods.
•  Aged, fermented, cured and left over food
• Cheeses like camembert, stilton, brie, gruyere, and parmesan
• Citrus fruits, pineapples, peach, nectarines, plums, strawberries, cranberries, dates, dried fruit, berries, bananas, pears
• Tomatoes, avocados, eggplant, capsicum, spinach
• Soy products like tempeh, tofu, soy sauce and miso
• Fermented  foods such as kombucha, sauerkraut,
• Pickles, Olives Tomato ketchup, tomato paste, mustard, vinegar
• Herbs and spices – nutmeg, cinnamon, star anise, all spice, chai, paprika,
• Smoked or canned meat and fish products – salami, ham, sausages, smoked salmon
• Shellfish
• Soy beans, peanuts
• Nuts – esp walnuts, peanuts and cashew
• Chocolate and cocoa/cacao based products
• Snacks and lollies with preservatives and artificial colourings
• Bone broth (the longer the cooking process the higher the amines

Diamine Oxidase (DAO) blockers to reduce:

• Alcohol
• Black tea
• Green tea
• Matcha
• Chai
• Coffee

Histamine liberators to reduce:

• Citrus fruits
• Kiwi– kiwi, lemon, lime,
• Pineapple
• Papaya
• Tomatoes
• Cocoa and chocolate
• Nuts
• Beans and legumes
• Wheat germ
• Food Additives – benzoate, sulphites, nitrites, glutamate, food dyes

Low histamine and amine level foods:

• Fresh vegetables
• Fresh meat (frozen is ok)
• Chicken (providing it is freshly cooked)
• Egg yolks (egg white – is a histamine liberator only when in its raw state)
• Fresh fish.
• Fresh milk and milk products
• Most cooking oils
• Most herbs
• Most fruit (except citrus, kiwi, pineapples, strawberries, bananas)
• Herbal teas (except black, chai, green, matcha)

 Anti-histamine and anti-inflammatory foods to increase:

• Apples
• Watercress
• Rocket
• Onions
• Garlic
• Holy Basil
• Thyme
• Nettle
• Peppermint
• Ginger

 Probiotics:

• Increase histamine – Lactobacillus casei, L reuteri L helveticus L Delbrueckii and L bulgaricus   
• Decrease histamine – Bifidobacterium infantis, B lognum L. rhamnosus GG and L plantarum