Histamine intolerance is one of the most overlooked conditions due to its broad and extensive list of symptoms that may also be signs of many other health circumstances as well. Histamine intolerance is the resistance towards “normal” levels of histamine in food caused by a decreased activity of the histamine-degrading enzymes diamine oxidase (DAO).

What is Histamine anyway?

You or perhaps someone you know have probably heard of antihistamine drugs that are typically used to overcome symptoms of allergies. So what is histamine exactly? Histamine is an important biochemical used to aid the immune system, the digestive system, and even the central nervous system, as it communicates signals from the body to the brain as a neurotransmitter. In humans, the highest histamine concentrations are found in the skin, lung, and stomach, with smaller amounts in the brain and heart. Histamine works by causing our blood vessels to swell and dilate, forcing our white blood cells (part of our immune system) to then attack the infection and caused acute inflammation. Inflammation is generally evidence that the body is reacting to potential threat. Histamine is always present when inflammation occurs, and excess histamine will result in symptoms that resemble inflammation. Excessive histamine will result in symptoms often indistinguishable from allergy; since allergy is essentially an inflammatory reaction, histamine is released in response to the allergen. Because it travels through the blood, histamine can affect our lungs, brain, skin, gut and sometimes the symptoms are broad and difficult to diagnose.

What Are The Symptoms of Histamine Intolerance?

  • Headaches
  • Migraines
  • Sneezing
  • Runny nose
  • Congestion
  • Vertigo
  • Dizziness
  • Anxiety
  • Abdominal cramps
  • Flushing
  • Hives or itchy skin
  • Tissue swelling
  • Fatigue
  • Digestive disturbances
  • Hypotension

What Causes an Individual to be Histamine Intolerant?

The immune system plays an extremely important role in histamine intolerance. With 70% of the immune system located in the gut, the health of our digestive tract is key in sustaining healthy histamine levels. Unfortunately, toxins and chemicals from the environment are very taxing on the gut and consequently, the immune system. This creates sensitivities and allergies to different compounds.

What Causes High Histamine Levels?

  • Allergies
  • Leaky gut
  • Alcohol
  • Bacterial Overgrowth
  • DOA deficiency

And foods such as:

  • Canned foods and ready meals
  • Fermented foods
  • Smoked meats
  • Shellfish
  • Legumes
  • Aged cheese
  • Nuts such as cashews and walnuts
  • Fruits such as bananas, strawberries, tomatoes, and pineapple
  • Foods with artificial preservatives and colours

DAO is the main enzyme responsible for breaking down ingested histamine. So if you’re deficient in DAO, you likely have symptoms of histamine intolerance.

Diamine Oxidase (DAO) blockers:

  • Alcohol
  • Black tea
  • Energy drinks
  • Green tea
  • Mate tea

Low Histamine Foods:

  • Freshly cooked meat, poultry (frozen or fresh)
  • Freshly caught fish
  • Eggs
  • Gluten-free grains: rice, quinoa
  • Pure peanut butter
  • Fresh fruits: mango, pear, watermelon, apple, kiwi, cantaloupe, grapes
  • Fresh vegetables (except tomatoes, spinach, avocado, and eggplant)
  • Dairy substitutes: coconut milk, rice milk, hemp milk, almond milk
  • Cooking oils: olive oil, coconut oil
  • Leafy herbs
  • Herbal teas

If the body is not already taxed from environmental and ingested toxins, than foods with high histamine levels should not be an issue as the body can regulate histamine when everything else is working properly. Trying to eliminate toxins found in foods, hygiene products and the environment are key to reducing the toxic load on the body. Medications such NSAIDS, antidepressants, antihistamines, antibiotics and immune modulators can also lower DOA enzymes that aid in histamine regulation. It is important to keep a personal inventory of toxins we are exposed to and attempt to reduce them as much as possible. The idea is to remove high histamine foods for 1-3 months until our level of histamine enzymes return to normal then re- integrate foods when levels of diamine oxidase are back to normal and when your gut is working optimally.

Testing For Histamine Intolerance:

Elimination: As previously mentioned, one method is to completely eliminate certain foods and stimuli, and reintroduce them slowly to see if there is a sensitivity.
Blood Testing: Getting a blood test to check for levels of DAO; a high ratio of histamine/DAO signifies that you are ingesting too much histamine and that you do not produce enough DAO to break it down.

Natural Solutions For Histamine Intolerance

It is important to get to the root cause of histamine intolerance and to take care of that rather than to treat its symptoms. Here are a few tips to help histamine sensitivity:

Diet: Use the elimination diet to take allergenic foods out of your system for 1-3 months and slowly reintroduce and monitor how your body reacts.
Supplement: taking a DAO supplement may aid in getting to the source of the issue by aiding in breaking down histamine. Quercetin, Stinging Nettles, Bromelain, Butterbur and Vitamin C have also been shown to help decrease histamine levels.
Reducing Inflammation: Reducing inflammatory foods, healing the gut, and even reducing stress are good places to start when looking to reduce your body’s negative response to histamine.