What Should You Avoid Eating If You Have IBS?

Many people who experience histamine sensitivity describe that certain foods tend to work less well for them — especially foods that are aged, cured or fermented. Some fruits, vegetables and drinks can also feel more challenging for certain individuals. Reactions vary widely from person to person, and it often takes some personal tracking to understand what you react to. Why Do Some Foods Contain More Histamine? Histamine is formed in food when bacteria are allowed to grow, particularly during storage, curing, fermentation or when leftovers are kept too long.The longer a food is stored, the higher its histamine content tends to be. Because of this, many people find that fresh foods are often easier to tolerate than leftovers or processed foods. How food is stored, handled and cooked can also influence histamine levels. Foods Commonly Higher in Histamine Below are examples of foods that many people with histamine sensitivity report reacting to.Tolerance varies — this list is a guide, not a strict rulebook. Animal Products Aged cheeses (parmesan, brie, camembert) Cured meats (salami, ham, sausages) Smoked or canned fish (tuna, mackerel, sardines) Leftovers that were not cooled quickly Liver and organ meats Fermented Products Sauerkraut Soy sauce, tamari, miso Kimchi Drinks Red wine, beer, champagne Coffee and energy drinks Fermented teas Vegetables & Fruit Tomato Spinach Aubergine (eggplant) Strawberries Avocado Citrus fruits (may also act as histamine-releasers for some) Foods That May Act as Histamine-Releasers Some foods are low in histamine but are described by some people as stimulating the body’s own release of histamine. These are sometimes referred to as “histamine liberators.” Commonly mentioned examples include: Chocolate Shellfish Nuts Banana Egg white Alcohol (especially red wine and beer) Certain preservatives and colourings (specific E-numbers) The effect is highly individual — and for many, the combination of several histamine-affecting foods at the same time has a greater impact than any single food. Lower-Histamine Options Even though the “avoid” list may feel long, many people with histamine sensitivity describe that certain foods tend to work better for them. Individual tolerance varies, but the following examples are frequently mentioned in low-histamine guides and by individuals who follow a low-histamine approach: Protein Fresh chicken, turkey Carbohydrates Rice, quinoa, potatoes, buckwheat Vegetables Zucchini, broccoli, cauliflower, lettuce Fruit Pear, apple, blueberries, Fats Olive oil, Coconut oil Tips for Managing Histamine in Daily Life Many people find the following strategies helpful: Choose fresh ingredients and cook meals right away Avoid long-stored leftovers — or cool them quickly and eat within 24 hours Read ingredient lists carefully Cook at home to stay in control of all ingredients Keep a food and symptom diary to identify your personal patterns What Influences Histamine Levels Beyond Food? Although diet plays a role in histamine sensitivity, it’s rarely the whole picture.Gut health, stress levels and medication use can also influence how the body handles histamine.

Histamine intolerance is a condition in which the body struggles to break down histamine at a sufficient rate, often due to reduced or inhibited activity of the enzyme DAO, which is produced in the small intestine. Histamine is a biochemical compound that is both produced naturally in the body and found in a range of foods.Histamine intolerance is not an allergy, but a condition often connected to how the gut functions and how much DAO is available to break down histamine. What Is Histamine? Histamine is a type of biogenic amine and occurs naturally in the body, where it participates in several important functions, including: immune responses regulation of stomach acid nerve signalling in the brain inflammatory processes Histamine is therefore both a signalling molecule produced by the body and something we consume through food.When the body’s handling of histamine does not work as it should, histamine levels can influence how a person feels. What Does “Intolerance” Mean? Histamine intolerance is not an allergy. In an allergy, the immune system overreacts to a specific substance. In histamine intolerance, however, the issue is a reduced ability to break down histamine that is already present. It is not caused by a fault in the immune system, but by a limitation or disruption in enzyme function.This type of intolerance can be temporary or long-lasting and is often influenced by factors such as gut health, stress, medication use or dietary habits. The DAO Enzyme – The Body’s Histamine Filter The key enzyme involved in histamine breakdown is diamine oxidase (DAO). DAO is produced primarily in the small intestine and is responsible for breaking down histamine from food. If DAO levels are low or if the enzyme is temporarily inhibited by factors such as impaired gut barrier function, medication, inflammation or microbial imbalance - histamine can accumulate and trigger various reactions. What Can Contribute to Histamine Intolerance? Histamine intolerance rarely has a single cause. It is more often the result of several interacting factors that affect how well the body can process and break down histamine: Genetic variations in enzyme activity. Some individuals have genetic differences that affect how much functional DAO enzyme is produced. Changes in the intestinal lining, for example in IBS, IBD or SIBO. Chronic stress or inflammation. Stress hormones and systemic inflammation can influence the intestinal environment and enzyme activity. Medications that inhibit enzyme function (sometimes referred to as MAO or DAO inhibitors), such as certain antibiotics, medications used for stress, depression, pain, high blood pressure and some treatments for Alzheimer’s or Parkinson’s disease. Imbalances in the gut microbiota. Changes in microbial composition can affect how much histamine is produced or broken down locally in the gut. Hormonal fluctuations. Some individuals notice varying histamine tolerance throughout hormonal cycles, such as during menstruation. Histamine intolerance is therefore often complex and individual, rather than a single diagnosis with one clear cause. How Does Histamine Intolerance Differ from an Allergy? Although symptoms such as skin flushing, runny nose or headaches can resemble allergy-related reactions, the underlying mechanisms differ. In allergies: the immune system reacts to a specific allergen. large amounts of histamine are released rapidly. reactions usually appear immediately and can be confirmed through allergy tests. In histamine intolerance: the reaction is not immunological. the body has difficulty breaking down histamine. the issue is linked to limited DAO activity. Symptoms often develop gradually, especially when consuming several histamine-rich foods in a short period.There is currently no standardized test to definitively diagnose histamine intolerance, which makes detection more challenging than for allergies. What Does the Research Say? Research on histamine intolerance has grown in recent years, but there are still no universally accepted diagnostic criteria or treatment guidelines. Much of today’s understanding is based on a combination of scientific studies, clinical experience and individual symptom reports. Studies have explored potential links between: gut microbiota and histamine balance probiotic bacterial strains and DAO activity the role of diet in influencing both histamine intake and breakdown However, more high-quality studies are needed to clarify how these factors interact in practice and what determines an individual’s tolerance levels. Much of the current knowledge therefore comes from clinical observation and patient reports rather than established official guidelines.  

When dealing with food sensitivity, it’s not only what you eat that matters — but also how the body processes the food. By supporting the gut microbiota and adjusting dietary habits, you can create conditions for a calmer and more balanced digestive experience over time.