Histamine is a naturally occurring biogenic amine that regulates the body’s immune, digestive, and neurological systems. We produce histamine internally and consume it through our diet. Histamine intolerance occurs when the body lacks sufficient activity of the enzyme diamine oxidase (DAO), which breaks down ingested histamine. When this breakdown is inefficient, the histamine consumed from food builds up, leading to various allergy-like symptoms. Understanding the histamine content of common foods like mayonnaise is essential for managing symptoms.
Understanding Histamine in Food
A food’s histamine content is primarily determined by the action of bacteria on the amino acid histidine. Histamine is created when microorganisms possessing the enzyme histidine decarboxylase convert histidine, a protein building block, into histamine. This process allows bacteria to survive in acidic environments, which is why fermented foods are particularly high in histamine.
Fermented, cured, or aged products consistently contain higher levels of histamine than their fresh counterparts. Examples include aged cheeses, cured meats, sauerkraut, and alcoholic beverages. The longer a protein-rich food is stored, the more opportunity exists for histamine-producing bacteria to multiply, leading to a greater accumulation of the compound.
Microbial activity also highlights the issue of food freshness and storage. If protein-containing foods are not kept at cold temperatures or are stored as leftovers for an extended time, the bacterial conversion of histidine to histamine continues. Since histamine is heat-stable, cooking or reheating spoiled food will not destroy the histamine already produced. Poor temperature control or prolonged storage time significantly increases the histamine load in any food.
Assessing Standard Mayonnaise Ingredients
Traditional mayonnaise is an emulsion primarily consisting of oil, egg yolk, and an acid. Commercial versions often contain several other ingredients that influence its histamine potential. Fresh egg yolks and neutral oils, such as sunflower or canola oil, are considered low in histamine. However, egg whites may be a histamine liberator, which is why some low-histamine recipes exclusively use the yolk.
The acid component often introduces histamine risk. Store-bought mayonnaise commonly uses distilled white vinegar, which is a fermented product and can contain moderate levels of histamine. Vinegar, along with other fermented acids like apple cider vinegar, can also act as a histamine liberator, potentially triggering the body’s own cells to release stored histamine.
Alternatively, some commercial brands use lemon juice concentrate as the acid. While fresh lemon is generally better tolerated than vinegar, citrus fruits are listed as common histamine liberators. Commercial mayonnaise often includes mustard for flavor and emulsification. Since mustard is a condiment made with vinegar, it introduces another source of histamine into the final product.
The Final Verdict on Histamine Levels
The overall histamine content of mayonnaise depends less on the egg and oil base and more on the type of acid and other ingredients used. Due to the presence of vinegar, mustard, or lemon juice, most standard, store-bought mayonnaise brands are classified as moderate to high in histamine. This makes commercial options problematic for those with histamine sensitivity.
The safest option for managing histamine intolerance is freshly prepared, homemade mayonnaise. This allows for strict control over the ingredients, such as using only fresh egg yolks and selecting a well-tolerated acid. This approach potentially avoids all fermented ingredients. If fresh lemon juice is not tolerated, a small amount of non-fermented, food-grade citric acid can be used as a substitute for acidity.
Regardless of whether it is store-bought or homemade, the freshness of mayonnaise is paramount. Once the jar is opened or the product is made, the risk of bacterial proliferation increases, leading to a rapid rise in histamine content. Mayonnaise should be consumed immediately upon opening or preparation, and leftovers should be avoided to minimize the histamine load.