Nutrition and Diet: What not to eat with MCAS? A Guide to Low-Histamine Eating

October 15, 2025 •

4 min read

According to the Mast Cell Disease Society, many patients with mast cell disease report symptom improvement with dietary changes, although these changes vary from person to person. Learning what not to eat with MCAS is a foundational step in managing symptoms for many, as dietary histamine and other food triggers can exacerbate reactions.

Quick Summary

Discover which foods to avoid for Mast Cell Activation Syndrome (MCAS). Learn about high-histamine foods, histamine-releasing ingredients, and practical tips for navigating a low-histamine diet to help manage symptoms.

Key Points

Avoid Aged and Fermented Foods: Products like aged cheeses, cured meats, sauerkraut, and wine are high in histamine due to their production process.
Eat Freshly Cooked Meals: Histamine levels rise in food over time, so consuming freshly prepared meals and avoiding leftovers is a key strategy for many.
Be Cautious with Specific Fruits and Vegetables: Certain produce items like tomatoes, spinach, avocado, and citrus fruits can act as histamine liberators, prompting your body to release its own histamine.
Limit Processed Foods and Additives: Artificial dyes, preservatives, and flavor enhancers like MSG can be dietary triggers for MCAS symptoms and should be avoided.
Use an Elimination Diet: Due to individual variation, working with a dietitian on a structured elimination and reintroduction diet is the most reliable method for identifying your specific food triggers.

Understanding Mast Cell Activation Syndrome and Your Diet

Mast Cell Activation Syndrome (MCAS) is a complex and often debilitating condition where mast cells, a type of white blood cell, release an excessive amount of chemical mediators at inappropriate times. This can cause a wide range of symptoms affecting various systems in the body, including skin, cardiovascular, respiratory, and gastrointestinal issues. While there is no universal diet for all MCAS patients, many find relief by identifying and avoiding food triggers that either contain high levels of histamine or provoke the release of histamine from mast cells. Implementing a low-histamine dietary approach is a common and proactive strategy, but it requires careful attention and experimentation, often with the guidance of a healthcare provider or dietitian.

High-Histamine Foods to Avoid

Histamine is a natural compound produced in the body, but it is also present in many foods. For individuals with MCAS, consuming high-histamine foods can contribute to a heightened symptom load. Minimizing or eliminating these foods is a crucial first step.

Fermented and Aged Foods

Fermentation and aging processes increase the histamine content in food as bacteria break down proteins. A low-histamine diet typically excludes:

Aged Cheeses: Parmesan, cheddar, Swiss, Roquefort, and other aged cheeses.
Cultured Dairy: Yogurt, kefir, and buttermilk.
Fermented Vegetables: Sauerkraut, kimchi, and pickles.
Soy Products: Soy sauce, tempeh, and miso.

Processed and Cured Meats

The curing and aging of meats also lead to high histamine levels. These include:

Cured and Processed Meats: Salami, sausages, prosciutto, bacon, and hot dogs.
Leftovers: Histamine levels increase significantly over time, making leftovers a common trigger. Cooking and eating meat and fish fresh is recommended.

Certain Fish and Seafood

While some fresh fish is well-tolerated, specific types and preparations are high in histamine:

Canned, Smoked, or Salted Fish: Tuna, mackerel, sardines, and herring.
Shellfish: Mussels, lobster, and crab can be particularly problematic.

Beverages and Alcohol

Certain drinks, especially fermented ones, are notoriously high in histamine:

Alcohol: Wine, beer, and champagne.
Fermented Drinks: Kombucha.
Other Beverages: Black tea and energy drinks can inhibit the DAO enzyme that breaks down histamine.

Histamine-Releasing and Enzyme-Blocking Foods

Beyond just high-histamine content, some foods, known as "histamine liberators," can trigger the body's mast cells to release their own histamine, while others block the enzyme (Diamine Oxidase or DAO) that helps break it down.

Fruits and Vegetables

Fruits: Citrus fruits (oranges, lemons), strawberries, avocado, pineapple, papaya, and bananas.
Vegetables: Tomatoes and spinach are common liberators.

Nuts and Legumes

Nuts: Walnuts and peanuts.
Legumes: Lentils and beans.

Miscellaneous Items

Chocolate and Cocoa: High in both histamine and liberators.
Food Additives: Artificial dyes, flavorings, and preservatives.
MSG: A flavor enhancer known to trigger symptoms in some patients.

Comparison of Food Choices for MCAS

This table provides a snapshot of high-histamine and potentially triggering foods versus safer, lower-histamine alternatives. Remember that personal tolerance can vary.


Food Category	Foods to Avoid (High-Histamine / Liberator)	Foods to Favor (Lower-Histamine)
Dairy	Aged cheese (Parmesan, cheddar), yogurt, kefir	Fresh mozzarella, butter, plain milk (if tolerated)
Meat & Fish	Cured meats (salami), leftovers, canned fish (tuna, sardines)	Freshly cooked poultry, cod, pollock; quickly frozen fish
Fruits	Strawberries, citrus, avocado, tomatoes, bananas	Apples, berries (blueberries), pears, melons, green tomatoes
Vegetables	Spinach, eggplant, pickles	Asparagus, broccoli, cucumbers, kale, onions
Grains	Wheat products (some find), yeast extract	Gluten-free grains (rice, quinoa, oats)
Beverages	Alcohol (wine, beer), black tea, kombucha	Water, herbal teas (non-citrus)

A Path Forward: Implementing an Elimination Diet

Given the individualized nature of MCAS, the most effective strategy for identifying your specific triggers is to work with a healthcare professional on an elimination diet. This process typically involves removing all high-histamine and known liberator foods for a period and then carefully reintroducing them one by one while keeping a detailed food journal. This methodical approach helps pinpoint exactly which foods provoke a reaction and allows you to build a personalized, symptom-minimizing diet. It's also important to focus on fresh, whole foods and minimize processed items. The Mast Cell Disease Society, Inc. provides additional resources and guidance on this topic.

Conclusion

Managing Mast Cell Activation Syndrome requires a highly personalized approach, and dietary modifications are a critical component for many individuals. Knowing what not to eat with MCAS involves avoiding high-histamine foods like aged cheeses, fermented products, processed meats, and certain fruits and vegetables. Equally important is being mindful of leftovers and foods that act as histamine liberators. By working with a medical professional on a carefully executed elimination diet, patients can identify their unique food triggers and establish a nutritious, well-tolerated diet that helps manage their symptoms and improve their overall quality of life.

Frequently Asked Questions

The primary dietary consideration for MCAS is to reduce your intake of high-histamine foods and foods that trigger the release of histamine in the body. This is often achieved through a low-histamine elimination diet.

No, it is generally recommended to avoid leftovers. Histamine levels increase as food, especially meat and fish, ages. Eating food fresh is a key strategy for managing dietary histamine.

You should avoid aged and matured cheeses, such as parmesan, cheddar, and Roquefort, as they are high in histamine. Some individuals may tolerate very fresh cheeses like mozzarella, but it is best to test with caution.

Many fermented foods, including sauerkraut, kefir, and kombucha, are high in histamine due to the fermentation process and should generally be avoided on a low-histamine diet. Some probiotics may be tolerated, but require careful selection.

Yes, chocolate and other cocoa-based products can be high in histamine and also act as histamine liberators, making them a common trigger for MCAS symptoms.

No, only specific fruits and vegetables are common triggers. Items like spinach, tomatoes, citrus fruits, and avocado should be avoided, while many others like apples, broccoli, and cucumbers are generally well-tolerated.

No, alcohol, particularly wine and beer, is considered a significant trigger for MCAS symptoms and should be avoided. It is high in histamine and can also trigger its release.