What is a Low Histamine Diet?

Histamine is a food chemical naturally found in many of the things that we eat on a day-to-day basis. It is normal to consume this food chemical. For most people the histamine that we consume goes on to be broken down by an enzyme called diamine oxidase (DAO). This enzyme keeps us in a state of equilibrium. It prevents complications that can happen from a buildup of excess histamine in the body.

However, some people have difficulty degrading histamine in the body, which can result in excess histamine and therefore symptoms. Common symptoms include allergy-type symptoms. Such as itching, hives, facial swelling, tightening in the throat, chest pain, and watery eyes and nose. Many people also experience digestive problems such as heartburn, reflux, abdominal pain, and diarrhea. 

Sensitivity to histamine in foods can result from various conditions, including histamine intolerance and mast cell activation syndrome. While I won’t be covering the background information on these conditions in today’s post, I do talk all about the pathogenesis of histamine sensitivity in my first histamine intolerance post. 

My main focus for today’s post is HOW to implement a low histamine diet plan. In particular, we will be reviewing the timeline of this elimination diet, foods to include, and foods to avoid. As well as how to assess whether the diet is working to resolve symptoms of histamine intolerance. 
Keep in mind, this is a restrictive diet. It is therefore highly recommended to work with a professional registered dietitian who is well-versed in how to appropriately implement a low histamine diet. Additionally, not everyone has issues with histamine. So talk to a professional if you feel this might be an avenue you would like to explore to manage your symptoms.

Histamine in Foods: The Basics

Histamine intolerance has a dosing effect. Think about your tolerance level like a bucket. You may be able to have a small amount. But it is possible that you’ve been overfilling that bucket (unintentionally of course!) It would be impossible to follow a no-histamine diet and that is certainly not the goal here. Instead, the goal is to simply reduce the build-up in your “histamine bucket” to potentially relieve symptoms.

Histamine is produced when foods have the chance to develop more bacteria. For this reason, fermented foods, aged foods, and foods that are not as fresh (ie. leftovers) are likely to cause more symptoms.

Since bacterial production plays a big role in histamine development, food preparation is a very important consideration on a low histamine diet. As proteins break down in foods, histamine is released. This is especially true for meats, fish, and shellfish. Therefore, anything with leftover meats has a ‘high histamine potential’ – think 2-day-old chicken stir-fry or cured/aged charcuterie meats for example. That being said, we can stall the production of histamine by storing foods properly. It is recommended that if you don’t eat something immediately or within 24 hours of cooking – it is best to freeze it. Extremely cold temperatures can greatly slow down the production of histamine in leftovers. This is also true for raw meats. Store things like uncooked chicken breast or steak in the freezer rather than the fridge. To protect against bacterial development as much as possible.

When it comes to a low histamine diet, there are 2 subcategories we need to consider:

Foods Naturally High in Histamine

These are foods that naturally have high levels of histamine. Often due to the bacterial breakdown of the foods as mentioned above. Foods that undergo either intentional or unintentional bacterial processes such as fermentation, aging, curing, or distilling would naturally be higher in histamine. Here is a more extensive list of high histamine foods:

• Cured and aged meats or fish – processed deli meats, charcuterie meats, smoked salmon, pickled fish
• Shellfish
• Fermented dairy products – yogurt, mature/aged cheeses, sour cream, buttermilk, and kefir
• Fermented soy products such as tempeh, soy sauce, miso, and tamari
• Pickled and fermented vegetables – sauerkraut, kimchi, pickles, olives
• Other fermented products such as kombucha, vinegars, and sauces that contain these (eg. ketchup or salad dressing containing vinegar)
• Alcoholic beverages, especially red wine
• Chocolate – cocoa-based products are made from fermented cocoa seeds, which is why it also falls into this category!
• Eggplant
• Spinach and tomatoes are high in histamine, but also act as histamine liberators (see below)

Foods that are Histamine Liberators

These are foods that aren’t naturally high in histamine themselves, but can trigger your cells to release more histamine. The foods with histamine-releasing properties include:

• Citrus fruit. Including lemons, limes, oranges, grapefruit
• Other fruit including papaya, raspberries, strawberries, pineapple, and overripe fruit in general
• Excess amounts of dried fruit (it is suggested to limit to 1-2 tbsp per serving)
• Tomatoes and tomato products
• Spinach
• Avocado
• Pumpkin
• Walnuts. Some lists suggest all nuts should be limited. But walnuts are listed to be one of the most likely to cause complications of histamine intolerance
• Pumpkin seeds
• Certain spices including cinnamon, curry powder, cloves, anise, chili powder, nutmeg, and thyme

There are also a few products that inhibit the activity of DAO (the enzyme that breaks down histamine), which can also lead to a histamine build-up in the body. This includes black and green teas, and alcohol.

How to Implement a Low Histamine Diet

Now that you know more about what foods to avoid and eat on a low histamine diet, let’s chat about how this diet should be implemented. 

This is meant to be a short term, 4 week diet done under supervision of a registered dietitian. In order to assess response. If you do feel better and have a measurable reduction in symptoms, it is then recommended to liberalize your diet. This is done by strategically add foods back in – to determine your personal threshold. Chances are you won’t have to be SUPER strict with all of the foods from the original elimination phase in the long run. 

If this diet does not work for you, you may not have a histamine intolerance. Or your medications may not be adequately optimized. While diet is important with histamine intolerance, sometimes pharmacological therapies also play a big role in symptom relief. See more about medications for histamine intolerance here. 

At the end of the day, allergy-type symptoms are very complex. They are often related to several different triggers – both dietary triggers and non-food triggers like environmental factors. Work with your registered dietitian and immunologist/allergist to develop a plan that works for you!