What is histamine?
HIstamine is a chemical naturally produced by the body and plays an important in our body. It’s most well-known for its immune response – increasing heat, redness, itching and sinus symptoms – and the common medication that helps to reduce these symptoms – antihistamines.
Contrary to the prevalence of anti-histamines, histamine is an important aspect of the inflammatory response. It is produced by basophils and mast cells to dilate blood vessels, increase blood flow and allow other immune cells to reach the area, which help to repair damage and fight off pathogens.
Other (less well-known) roles of histamine are:
- As a component of stomach acid
- As a neurotransmitter controlling libido, cognition and waking you up – remember that some antihistamines can make you drowsy?
So why is it a problem?
Histamine may become a problem if levels continuously build up in the bloodstream and become too high. This is called histamine intolerance. It’s important to clarify that histamine intolerance is due to an accumulation, rather than an immediate release of histamine (like in an allergic reaction).
Picture a bubble-bath. It’s great when the bubbles remain in the bath, however if the water keeps running, the bath eventually spills over and bubbles are now the enemy!
This accumulation may be due to inability to break down histamine, numerous allergies intestinal permeability, dysbiosis or a high intake of histamine-rich food and drink.
Symptoms of histamine intolerance vary, but some common ones include: rashes, hives, runny nose, rashes, migraines, sleeping difficulties, digestive upset (constipation and/or diarrhea), nausea and changes to blood pressure.
This can be investigated and diagnosed with your GP.
How can I reduce my high levels of histamine?
Once you know you have high levels of histamine, you can modulate your diet to help reduce them to normal levels.
There are three things to consider in regards to your diet.
- Limit foods that contribute to histamine
- Know which foods are low in histamine
- Include foods that assist in the metabolism of histamine
Foods that contribute to histamine levels are foods naturally high in histamine, or that provoke histamine release.
- Any known allergies
- Pickled foods & fermented milk products
- Dried fruit
- Smoked meat products
- Beans and pulses – chickpeas, soy-beans, peanuts
- Nuts – walnuts, cashew nuts
- Chocolates and other cocoa based products
- Salty snacks, sweets with preservatives and artificial colourings
- Black, green and mate tea
- Energy drinks
[There is a great list here: http://www.foodmatters.com/article/what-is-histamine-intolerance.]
To focus on foods low in histamine, follow the JERF principles! In particular:
- Fresh, unprocessed food such as:
- Fresh meat and fish, fruit, except strawberry, citrus
- Fresh fruits (exception: strawberries)
- Fresh vegetables (exception: tomatoes & cabbage)
- Whole grains including: rice, corn, millet, oats, sorghum
- Egg yolk
- Milk & dairy products (without additives)
- Coconut & rice milk
- Herbal teas – with the exception of those listed below
To help lower histamine levels:
- Include ingredients that reduce the release of histamine
Quercetin (found in apples, peppers and berries) and vitamin C (high in dark leafy greens, kiwifruit, broccoli, berries and oranges) help to stabilize mast cells, which inhibits the release of histamine.
- Include ingredients that help metabolise histamine
Histamine is broken down via two enzymes – predominantly Diamine Oxidase (DAO) and also Histamine N-methyltransferase (HNMT). These enzymes require adequate co-factors to work efficiently, such as vitamin B6, copper and vitamin C.
How do I know if this is right for me?
A low-histamine diet can be quite limiting, therefore it is not recommended unless histamine intolerance is diagnosed.
However, if you suspect this may be you, enjoying a whole-foods, JERFing diet, and limiting processed foods is a great place to begin while you are waiting for confirmation.