The question of what foods have monoamine oxidase is based on a common misunderstanding. Foods do not actually contain the enzyme monoamine oxidase (MAO); rather, they contain compounds called monoamines, most notably tyramine. The body's MAO enzyme is responsible for breaking down tyramine. For individuals taking Monoamine Oxidase Inhibitor (MAOI) medications, this enzyme is blocked, meaning that tyramine from food is not processed properly and can build up in the body. A dangerous surge in tyramine can trigger a hypertensive crisis, a severe spike in blood pressure that can be life-threatening. Consequently, people on MAOIs must carefully manage their diet to avoid tyramine-rich foods.
High-Tyramine Foods to Avoid
The risk of a hypertensive crisis is directly related to the amount of tyramine consumed. The longer a food is aged, fermented, cured, or improperly stored, the higher its tyramine content can become. Here are the key food categories to strictly avoid or significantly limit:
Aged, Fermented, and Pickled Products
- Aged Cheeses: Cheddar, Swiss, Parmesan, blue cheese (Stilton, Gorgonzola), Camembert, Brie, feta, and any cheese that has been aged or matured. Fresh cheeses like cottage cheese, ricotta, and cream cheese are generally safe.
- Fermented Soy Products: Miso soup, soy sauce, teriyaki sauce, tempeh, fermented tofu (bean curd), and other soy-based condiments.
- Pickled and Fermented Vegetables: Sauerkraut, kimchi, and other pickled vegetables.
- Yeast Extracts: Concentrated products like Marmite and Vegemite.
- Probiotic Drinks: Certain fermented beverages like kombucha and kefir can also contain high levels of tyramine.
Cured, Smoked, and Processed Meats
- Cured Meats: Dry-type summer sausages, salami, pepperoni, and other cured sausages.
- Processed Meats: Bacon, hot dogs, corned beef, bologna, and other luncheon meats.
- Smoked or Pickled Fish: Items like pickled herring, smoked salmon, or caviar.
- Aged Game and Poultry: Improperly stored or aged chicken liver and other game meats.
Certain Fruits and Vegetables
- Overripe Fruits: Bananas (especially the peel), avocados, and raisins.
- Specific Beans: Broad beans, fava beans, and snow peas contain other monoamines that can interfere with MAOIs.
Alcoholic Beverages
- Tap and Home-Brewed Beer: These often contain higher tyramine levels than pasteurized, bottled beers.
- Certain Wines: Red wines, sherry, vermouth, and fortified wines can be high in tyramine.
Low-Tyramine Foods to Enjoy
Many food options are low in tyramine and can be safely incorporated into an MAOI diet. The general rule is to opt for fresh, properly stored, and non-fermented options.
Fresh, Uncured Proteins
- Fresh Meat, Poultry, and Fish: Freshly cooked chicken, turkey, beef, and fish are safe. It is crucial to eat these within 24-48 hours of preparation or freeze them to prevent tyramine buildup.
- Eggs: Fresh eggs are acceptable.
Pasteurized Dairy and Dairy Alternatives
- Fresh Cheeses: Cottage cheese, ricotta, cream cheese, and American cheese.
- Milk: Fresh, pasteurized milk and milk alternatives are safe.
- Yogurt and Ice Cream: Unfermented varieties are typically fine in moderation.
Fresh and Properly Stored Produce
- Most Fresh Vegetables: All fresh, frozen, or canned vegetables are generally safe, except for the high-tyramine beans.
- Most Fruits: Fresh fruits, apart from overripe or dried varieties mentioned, are low in tyramine.
Grains and Condiments
- Grains: Plain breads, cereals, pasta, and rice are safe choices.
- Condiments: Ketchup, mustard, and most salad dressings that do not contain fermented ingredients are fine.
Tyramine Content: High vs. Low Foods
Understanding the contrast between food preparation methods is key to adhering to an MAOI diet. This comparison highlights common foods and their tyramine levels based on processing.
| Food Category | High-Tyramine Examples | Low-Tyramine Examples |
|---|---|---|
| Dairy | Aged Cheddar, Blue Cheese, Brie | Cottage Cheese, American Cheese, Fresh Milk |
| Meat | Salami, Pepperoni, Cured Ham | Fresh Chicken, Fresh Fish, Fresh Beef |
| Soy | Soy Sauce, Miso, Tempeh | Soy Milk, Fresh Soybeans, Unfermented Tofu |
| Beverages | Draft Beer, Red Wine, Sherry | Bottled Beer (pasteurized), Spirits (vodka, gin) |
| Vegetables | Sauerkraut, Kimchi, Fava Beans | Fresh Broccoli, Lettuce, Carrots |
| Fruits | Overripe Bananas, Dried Raisins | Fresh Bananas, Apples, Berries |
| Condiments | Fish Sauce, Yeast Extracts (Marmite) | Ketchup, Mustard, Mayonnaise |
The Importance of Proper Food Handling
Beyond simply choosing the right foods, proper food handling is paramount for anyone on an MAOI diet. Tyramine levels increase over time, so freshness is critical. All food should be consumed as fresh as possible, and leftovers should be consumed within 48 hours or frozen immediately. Improperly stored or spoiled food poses an additional risk and should be discarded. It is also important to practice safe food storage by keeping cold foods properly refrigerated and following best-before or use-by dates meticulously.
Conclusion: Prioritizing Safety and Consultation
While the concept of what foods have monoamine oxidase is a misnomer, the dietary restrictions surrounding MAOI medications are very real and necessary for safety. The key takeaway is to focus on consuming fresh, minimally processed foods while avoiding aged, fermented, cured, or improperly stored items that are rich in the monoamine tyramine. Given the serious nature of a hypertensive reaction, it is essential for anyone on an MAOI to consult with their healthcare provider and a dietitian to create a personalized, safe dietary plan. For more detailed information, consult authoritative medical sources on the subject. MAOIs and diet: Is it necessary to restrict tyramine? - Mayo Clinic
Disclaimer: This article is for informational purposes only and is not a substitute for professional medical advice. Always consult with a qualified healthcare provider before making any dietary changes, especially if you are taking medication.
