Histamine is a naturally occurring biogenic amine found in the body, where it acts as a neurotransmitter and plays a role in immune responses. It is also present in many foods, formed when the amino acid histidine is broken down. When consumed, the histamine from food is normally processed by the body without issue. Concerns about dietary histamine often arise when considering commonly consumed foods, such as french fries.
Understanding Histamine Intolerance
The reason some individuals are concerned about the histamine content in food relates to a proposed condition known as Histamine Intolerance (HIT). This condition occurs when the body cannot efficiently break down the histamine consumed through the diet, leading to a build-up in the system. The body relies on the digestive enzyme Diamine Oxidase (DAO) to degrade this extracellular histamine in the gut.
DAO is the primary enzyme responsible for metabolizing histamine ingested from food. If the activity or levels of this DAO enzyme are low, the body’s capacity to process dietary histamine is reduced. This reduced capacity means that even normal amounts of histamine in food can exceed an individual’s tolerance threshold.
When this threshold is exceeded, the excess histamine can trigger a variety of symptoms that often resemble an allergic reaction, such as headaches, gastrointestinal upset, or skin flushing. Foods that are highly aged, fermented, or processed naturally contain higher levels of histamine, placing a greater load on the DAO enzyme.
Analyzing the Base Ingredients of French Fries
The primary ingredient in french fries, the raw potato, is naturally considered a low-histamine food. Freshly stored potatoes do not contain or stimulate the release of significant amounts of histamine, making them generally safe for individuals monitoring their dietary intake. The inherent composition of the potato itself contributes little to the histamine load.
However, commercially prepared french fries, particularly those that are pre-cut and frozen, often contain ingredients beyond just potato, oil, and salt. These additives can include stabilizers, color retention agents, and flavor enhancers. Certain common enhancers, such as monosodium glutamate (MSG), are recognized as potential histamine liberators, meaning they can trigger the release of histamine already stored in the body’s mast cells.
Although these additives may not contain histamine themselves, their presence can influence sensitivity and reaction in individuals with a reduced DAO capacity. Therefore, while the potato base is low in histamine, the overall formulation of a processed french fry product can introduce compounds that affect a sensitive person.
How Frying and Storage Affect Histamine Levels
The cooking method is a major factor that determines the final histamine content of french fries. While boiling or steaming vegetables tends to maintain or decrease histamine levels, the process of deep frying can significantly increase them.
This increase is largely due to the loss of moisture during the high-heat frying process. As the water content evaporates, the histamine present in the raw product becomes more concentrated in the finished fry. The high temperatures used in deep-frying also promote the formation of biogenic amines, including histamine, in the food matrix.
Beyond the initial cooking, the freshness of the product is highly influential; the longer the fries sit out after cooking, the higher the concentration of amines can become. Fries that are reheated or have been sitting under a heat lamp for an extended period will have accumulated significantly higher levels of histamine than those eaten immediately. For individuals with histamine sensitivity, consuming fresh, hot fries made from fresh oil is preferable to eating leftovers or a product that has been stored and reheated.