context: In some people, certain foods and drinks -- or things they contain -- can trigger a migraine. One well-accepted migraine trigger is tyramine. Tyramine is a substance found naturally in some foods. It's especially found in aged and fermented foods, such as: Aged cheeses Smoked fish Cured meats Some types of beer Also, foods high in protein may contain more tyramine if: They have been stored for a long time They have not been kept cold enough Because of its chemical structure, tyramine is called a monoamine. There's an enzyme in our bodies that breaks down monoamines called monoamine oxidase ( MAO). This enzyme helps process tyramine. If you get migraines and don't have enough MAO in your system, you could get headaches after you eat foods with tyramine. Scientists made the connection after anti-depression drugs that inhibit MAO went on the market in the 1950s. People taking the drugs began to get headaches and high blood pressure when they ate foods containing tyramine. Experts are still trying to understand how tyramine triggers migraines. One explanation is that it causes nerve cells in your brain to release the chemical norepinephrine. Having higher levels of tyramine in your system -- along with an unusual level of brain chemicals -- can cause changes in the brain that lead to headaches. If you want to cut down on tyramine to see if it helps, here are some foods to avoid and others to choose: Cheese and dairy foods. Higher in tyramine: Aged cheeses, cheddar, Stilton or blue, Camembert, Swiss, feta, Muenster, Parmesan Lower in tyramine: American cheese, cottage cheese, yogurt, fresh milk, farmer's cheese, cream cheese, sour cream, soy cheese, soy milk Meat, poultry, and fish . Higher in tyramine: Dry sausages, salami, pickled or smoked fish, caviar, aged chicken livers, soups or gravies made from meat extract Lower in tyramine: Fresh meat, poultry, fish, eggs; luncheon meats other than salami; canned meats or fish eaten when opened Fruits, veggies, and beans. Higher in tyramine: oranges, grapefruit, lemons, limes, tangerines, pineapple, fava beans, broad beans, sauerkraut, fermented soy foods, miso, tofu, kimchee, raw onions Lower in tyramine: Most fresh, canned, or frozen veggies; raisins Drinks. Higher in tyramine: Vermouth, tap beers, red wine Lower in tyramine: Decaffeinated coffee, tea, or soda; club soda; fresh or soy milk; bourbon; gin; rum; vodka Condiments . Higher in tyramine: Concentrated yeast extract, soy sauce, fish sauce, teriyaki sauce Lower in tyramine: Ketchup, mustard, Worcestershire sauce, salad dressing Most breads, pasta, or grains are low in tyramine. So are most sweets and desserts. Here are some other tips to help you cut the amount of tyramine in your diet: Choose fresh meats, poultry, or fish. Cook and eat them the day you buy them, or freeze them. Tyramine levels go up when foods are at room temperature. Store foods in the refrigerator or freezer. Thaw frozen foods in the refrigerator or microwave. Eat fresh produce within 2 days. Don't eat leftovers you've kept in the refrigerator for more than a day or two. Toss spoiled, moldy, or overripe foods. Don't eat smoked, aged, pickled, or fermented foods. Keep a headache diary for several months. It can help you and your doctor find out if tyramine or some other trigger is to blame for your migraines. Take note of the time and date the headache starts. Then answer these questions: How exactly does the migraine feel? Where does the migraine episode fall in your menstrual cycle? What have you eaten recently? Have you been exposed to other common headache triggers, such as a change in altitude, change in temperature, strong smells, bright lights, loud noises, changes in sleep habits, or unusual stress? Remember, headaches may not start for 24 hours after you eat certain trigger foods. That's why including the foods you've eaten during the past day or two may help you figure out if tyramine is part of the problem.