September 26, 2025 
 
 Do you find yourself feeling bloated after certain meals or waking up with a headache? Maybe part of your morning routine consists of taking medication to reduce your hives or flushing – but you haven’t figured out what exactly you’re allergic to? Trying to identify triggers, especially related to                                  diet                                               , can be very confusing and frustrating.                                                                  Our body has built-in protection – our immune system. Among other cells, our immune system also consists of mast cells, which can release a wide variety of chemical mediators such as:                                                                                 Histamine                                                                        Interleukins                                                           Prostaglandins                                                           Cytokines                                                           Chemokines                                                                  When you are exposed to an allergen, toxin, and/or injury, these chemical mediators, especially histamine can be released into your body. These chemical mediators can affect multiple organ systems including the respiratory, circulatory, integumentary, digestive, muscular and nervous system.                                                      Some symptoms of histamine intolerance can include headache, migraines, sinus symptoms, fatigue, hives, flushing, nausea, vomiting, digestive issues. However, if you’re struggling with mast cell activation syndrome (MCAS), your mast cells are over-producing histamines whether there is a trigger or not.                                                      Regardless if you’re struggling from MCAS or histamine intolerance, your diet stands at the centerpiece for healing because certain foods are high in histamine. And these foods may be contributing to your histamine intolerance symptoms.                                                      What Are Mast Cells and Histamine?                                                      Histamine lives inside your mast cells and play a large role in your immune system. Histamine sends a battle cry to your body’s cells and tissues when an invader is sensed. Your blood vessels dilate, which helps your body’s troops arrive as fast as possible to fight the invader.                                                      When                                  histamine is released                                   from your mast cells several things may happen:                                                                   Increased gastric acid secretion leading to bloating, flatulence, indigestion, constipation or diarrhea                                                           Increased heart rate                                                           Flushing                                                           Headache                                                           Itching                                                           Hives                                                           Sinus congestion                                                                  In rare, more serious cases, histamine can trigger asthma attacks or even cardiac arrest.                                                      We have four types of histamine receptors – H1, H2, H3, and H4. Antihistamine medications can block these histamine receptors. For example, blockers of H1 receptors can treat flushing, hives, headaches, and itching, and blockers of H2 receptors treat gastrointestinal symptoms, most commonly acid reflux.                                                      Although these medications can reduce symptoms, they aren’t treating the                                  root cause                                   of why you may feel like a bloated, itchy version of yourself.                                                      Since these chemical messengers released by your mast cells produce both a local and systemic effect – symptoms of histamine intolerance can be confusing and difficult to diagnosis.                                                      Mast Cell Activation Syndrome                                                                   Mast cell activation syndrome (MCAS) is a disorder, which is not yet fully understood. What we do know is signaling pathways can develop errors and cause histamine to be released at an inappropriate rate.                                                                  MCAS can contribute to symptoms of excess histamine including:                                                                   Fatigue                                                           Itching                                                           Hives                                                           Mood changes                                                           Asthma and wheezing                                                           Gastrointestinal distress – diarrhea, bloating, nausea                                                                  A few potential triggers of MCAS include:                                                                   Stress                                                           Fatigue                                                           Diet                                                           Medications –– antibiotics, narcotics, contrast dyes, NSAIDs                                                           Mold                                                           Infection                                                           Lyme disease                                                           Environmental toxins such as heavy metals                                                           Exercise                                                                  Contributing Factors to Histamine Intolerance                                                                   There are several contributing factors to histamine intolerance – your diet plays a role as well as stress levels and your gut health.                                                                  Irritable bowel syndrome (IBS) and small intestinal bacterial overgrowth (                                  SIBO                                  ) can also contribute to histamine intolerance. If you have an imbalance or overgrowth of bacteria in your small intestine – this can lead to                                  increased intestinal permeability                                  also known as                                  leaky gut syndrome.                                                      This increased gut permeability can allow for high histamine foods to enter the bloodstream which otherwise would stay in the gut – potentially leading to histamine intolerance.                                                                                        Histamine Found in Your Foods                                                                   The foods you eat are a major source of histamine in your body. If you’re struggling with histamine intolerance or mast cell activation syndrome, it’s important to first start with an elimination diet.                                                                  An elimination diet consists of avoiding foods high in histamine. You can then start to slowly add these foods back into your diet – taking note of which ones trigger your histamine intolerance symptoms.                                                      Foods which have high levels of histamine include:                                                                   Fermented dairy products such as cheese, sour cream, and yogurt                                                           Tuna and Mackerel                                                           Fermented vegetables such as kimchi, sauerkraut                                                           Raw and cured meat products                                                           Pickles                                                           Soybean paste                                                           Red pepper paste                                                           Mayonnaise                                                           Ketchup                                                           Fermented beverages – wine, beer, kombucha                                                           Chocolate                                                           Certain fruits and vegetables such as bananas, pineapple, tomatoes                                                                  Fermented                                   foods can potentially                                  feed bad gut bacteria                                   as well if you already have an unhealthy gut. These foods can subsequently contribute to conditions such as small intestinal bacterial overgrowth and irritable bowel syndrome.                                                      Fresh fruits and vegetables can also lead to histamine intolerance, which can make identifying your trigger foods a challenge.                                                      Not only do certain foods have higher histamine levels, but a                                  2017 study                                   found the way you prepare your food can have an effect on histamine. Grilling and frying food were found to increase histamine levels. Boiling food was found to have no effect and can even reduce histamine levels.                                                      Low Histamine Diets Can Be Tricky                                                      Low histamine diets can be a challenge no doubt. It’s a strict diet, which eliminates many popular foods.                                                      Fortunately, studies have actually shown changing to a                                  histamine-free diet                                   for only 4 weeks can show improvements of histamine intolerance symptoms as well as serum histamine levels.                                                      So you might be wondering just what can you eat on a low histamine diet? Fresh is best on a low histamine diet.                                                      Foods to fill your grocery basket with, for a low histamine diet includes:                                                                   Fresh and organic meat, poultry, pork, and fish (if you use frozen meat/fish, thaw quickly and use immediately)                                                           Vegetables such as arugula, beets, bell peppers, lettuce (not spinach), leeks, kale, carrots, cabbage, cauliflower, broccoli, zucchini, squash, and onions                                                           Gluten-free grains and rice                                                           Almond or coconut milk                                                           Fruits such as apples, peaches, apricots, blueberries, blackberries, melon, and mangoes                                                                  The challenge while on your low histamine diet lies in identifying what triggers your specific histamine response. Elimination diets can help dial in what triggers your individual histamine intolerance symptoms. What affects one person might not affect another.                                                      The stress often associated with food elimination diets can also contribute to histamine release so using a collaborative approach is key.                                  Stress                                                is also a key factor in SIBO and IBS – therefore working with a physician to develop your low histamine diet safely is helpful.                                                                  There is no single test to determine if you have a histamine intolerance or identify which foods you’re more sensitive to. But by working with an experienced physician to create a plan to help you discover those foods – you’re more likely to be successful and create your personalized low histamine diet.                                                                                                            This post was originally published on www.jjmd.com by Dr. Jessica Jellison.