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Mastering the Low Histamine Diet: What to Eat and What to Avoid 

What is a Low Histamine Diet?

The low histamine diet is an eating plan with a very specific purpose. The goal of the diet is to manage symptoms associated with a condition called histamine intolerance. In order to understand the purpose of this medical treatment, let’s first learn about what histamine is and how it works in the body.

Understanding Histamine in the Body

What comes to mind when you hear the word histamine? You may think of itchy eyes on a spring day or a sudden sneeze while petting a friendly dog. (Yup, those antihistamine commercials really are a part of your core memories!) 

Even if you’re unsure of what histamine is, you likely have some idea of its connection to allergies.

Histamine plays an important role in the immune system. Mast cells, which are a type of white blood cell, release histamine in response to various triggers, such as certain foods or environmental triggers (like pollen or pet dander). For example, if you have an allergy to a specific food, your immune cells release histamine to protect your body when you eat that food.

How the Low Histamine Diet Works

The low histamine diet can help with the management of histamine intolerance. The diet attempts to reduce foods that are high in histamine or could trigger the release of histamine.

Signs and Symptoms of Histamine Intolerance

Histamine intolerance is thought to have two main causes. The first is an overproduction of histamine as a result of certain conditions, such as allergies or Mast Cell Activation Syndrome (MCAS). The second is slowed histamine breakdown, which has been associated with certain medications, gastrointestinal conditions, and high stress levels. 

The main enzyme responsible for the breakdown of histamine is diamine oxidase (DAO). A low level of DAO can make it difficult for the body to break down histamine. For some people with histamine intolerance, low levels of DAO may play a role in their symptoms. 

Certain groups of people may be more prone to histamine intolerance and have trouble breaking down histamine, including older adults, individuals with gastrointestinal or gut disorders, and kidney or liver diseases. 

Common Symptoms to Look For

Histamine intolerance can share classic symptoms of an allergy such as a runny rose, rash, hives, and swelling of the lips, tongue, and throat. However, histamine intolerance is often referred to as a “whole-body condition”, meaning it can also cause other symptoms such as headaches, dizziness, low blood pressure, irregular heartbeat, and digestive symptoms. This wide range of symptoms often means histamine intolerance can be more difficult to diagnose.

How is Histamine Intolerance Diagnosed?

Diagnosing histamine intolerance can be challenging since there are no specific tests for it. A healthcare provider who is familiar with the condition can make a diagnosis based on a detailed history of symptoms, dietary habits, and any related health conditions. While not definitive, blood tests for DAO enzyme levels or histamine levels in the blood may also be conducted to assess how histamine is metabolized in your body. It’s also important to rule out any other conditions that can cause similar symptoms, such as allergies or gastrointestinal disorders. 

If histamine intolerance is suspected, your healthcare provider may then recommend trialing a low histamine diet. This involves removing high-histamine foods from your diet for a period of time (usually 2 to 4 weeks). 

Foods to Avoid on a Low Histamine Diet

When following a low histamine diet, the goal is to reduce the intake of foods that either contain high levels of histamine or trigger the release of histamine in the body. Since histamine intolerance affects people differently, there is often confusion around which foods to avoid on a low histamine diet.   Additionally, research on low histamine diets concluded that there is a lack of consensus as to what foods should be avoided. As a result of this, there isn’t universal agreement about the diagnosis and management of histamine intolerance. Navigating the confusion around which foods to avoid requires careful monitoring and guidance to develop a customized approach, which is why working with a dietitian can be helpful. 

While the “yes” and “no” food lists can vary depending on what source you look at, there are many similar themes. 

Examples of foods to avoid on a generalized low histamine diet include:

Fermented Foods

Fermented foods are avoided on a low histamine diet because they typically contain high levels of histamine. In this study, fermented foods were the only group of foods that were unanimously excluded in all low histamine diets. During the fermentation process, certain bacteria can produce histamine as a byproduct, causing histamine levels in the food to increase.

Fermented foods include fermented dairy (kefir, buttermilk, sour cream), fermented vegetables (sauerkraut, kimchi, pickles), and soy products (miso, tempeh, tofu). 

Aged Foods

The aging of foods can also increase the amount of histamine. Aged cheeses and processed and cured meats are usually avoided on the low histamine diet. Cheese is typically considered “aged” after 6 months or more and often includes parmesan, gouda, blue cheese, and cheddar. Examples of processed and cured meats include salami, pepperoni, sausage, smoked ham, bacon, and luncheon meats.

Canned and preserved foods

Other ways of preserving foods, such as canning, smoking, and pickling can increase histamine levels in the foods. Most low histamine diet lists recommend avoiding foods such as canned fish/meats, smoked meats, pickles, and foods preserved in vinegar.

Nuts

While nuts are not high in histamine, they can be problematic for some individuals with histamine intolerance due to their potential to trigger histamine release. Some low histamine diet resources list certain nuts to avoid, such as walnuts, cashews, and peanuts, while another resource lists “nuts and peanuts”. Whether nuts need to be avoided on a low histamine diet can vary based on individual tolerance and the type of nut. Working with a registered dietitian can be helpful in this situation to ensure your plan is individualized to you and your health concerns.  

Alcohol

It is recommended to avoid alcoholic beverages on the low histamine diet, particularly red wine and beer. Wine is high in histamine and beer is fermented, so it can trigger histamine release. In general, alcohol has also been reported to block the DAO enzyme that is needed to break down histamine.

Certain Fruits and Vegetables

Some fruits and vegetables naturally contain higher levels of histamine or produce it during ripening, adding to the overall histamine load in the body when eaten. These include tomatoes, spinach, eggplant, and avocados. 

Other fruits and vegetables may not contain significant amounts of histamine, but they can trigger the release of histamine in the body. This group includes citrus fruits, strawberries, bananas, and pineapple. As a result of this, these foods can lead to symptoms similar to those caused by high histamine foods. 

What are Histamine Releasers?

Studies show that certain foods, including legumes, chocolate, and vinegar, have been reported to trigger the release of histamine in the body. Although these foods are not inherently high in histamine, they can trigger the body’s mast cells to release histamine. 

Best Low Histamine Foods to Eat

When following a low histamine diet, it’s essential to focus on fresh, minimally processed foods that are naturally low in histamine. These foods can help minimize histamine intake and reduce symptoms for those with histamine intolerance. Here are some of the best low histamine food options: 

Fresh meats and poultry (unprocessed)

• Fresh, non-aged and unprocessed meats are low in histamine. It’s important to consume these meats as fresh as possible, as histamine levels can increase in meats over time.

• Examples include chicken, turkey, beef, lamb, pork.

Fresh fish (non-aged)

• Freshness is key, as fish histamine levels rise rapidly after they are caught. Avoid canned or aged fish such as tuna, sardines, and mackerel.

• Cod, haddock, plaice, and sole are lower in histamine compared to oily fish.

Dairy substitutes

• Non-dairy milks are good alternatives for those sensitive to histamine in cow’s milk

• Examples include coconut milk, rice milk, and almond milk (as tolerated)

Grains and starches

• Rice: white, brown, basmati, and jasmine rice

• Quinoa, oats, and millet are naturally low histamine options

• Potatoes and sweet potatoes are good starchy options that are low in histamine and well tolerated by most

Fresh fruits & vegetables (non-nightshades)

• Freshness is important. Avoid overripe or stored fruits and vegetables, as histamine levels can rise during storage.

• Low histamine vegetables include zucchini, carrots, cucumbers, bell peppers, lettuce, peas, cabbage, and green beans

• Low histamine fruits include apples, pears, mangoes, blueberries, melons, and cherries.

Herbs and spices

• Basil, parsley, cilantro, thyme, rosemary, and oregano are low in histamine and add flavor to meals without causing reactions

How a Registered Dietitian Can Help You

The low histamine diet is a medical treatment that is only meant to be tried for a short period of time. Therefore, it’s essential to work with an experienced registered dietitian who can help guide you through food eliminations and reintroductions so you can identify your unique triggers.

Conclusion: Is the Low Histamine Diet Right for You?

If you believe that you have histamine intolerance, the first step is to talk to your healthcare provider. They can assess your risk by looking at your health history and ruling out other potential conditions.  If warranted, your healthcare provider may recommend  trialing a low histamine diet with the help of a registered dietitian.