Histamine is a biogenic amine found naturally in many foods. Its content varies widely depending on how a food is processed and stored. Understanding the histamine content of common foods like sour cream is important for individuals managing dietary sensitivities. For those with a sensitivity, consuming high-histamine foods can lead to uncomfortable physical reactions.
Understanding Histamine Intolerance
Histamine is a natural compound that serves multiple functions in the body, acting as a neurotransmitter and playing a significant part in the immune system’s response to foreign substances or injury. It is stored within mast cells and basophils, and its release causes the familiar symptoms associated with allergic reactions, such as inflammation and itching. The body naturally manages histamine levels through specific enzymes that break it down.
Histamine intolerance (HI) occurs when there is an imbalance between the amount of histamine consumed or released internally and the body’s capacity to break it down. The primary enzyme responsible for degrading histamine ingested through food is Diamine Oxidase (DAO), which is mainly produced in the intestinal lining. If the activity of the DAO enzyme is insufficient, the histamine absorbed from the digestive tract can accumulate in the bloodstream, exceeding the individual’s tolerance threshold.
The symptoms of histamine intolerance are varied and can mimic those of an allergy, often affecting multiple systems in the body. Common manifestations include headaches, migraines, skin issues like hives or itching, and digestive upset such as abdominal pain or diarrhea. Symptoms can also involve the cardiovascular system (irregular heartbeats or blood pressure fluctuations) or the respiratory system (nasal congestion or wheezing).
Why Fermentation Increases Histamine Content
Sour cream is considered a food with elevated histamine levels, and the reason is directly linked to its production method. Unlike fresh cream, sour cream undergoes a controlled process of fermentation. This process involves the introduction of specific bacterial cultures, typically lactic acid bacteria, which are responsible for thickening the cream and giving it its characteristic tangy flavor.
These lactic acid bacteria possess a specific enzyme called histidine decarboxylase. This enzyme acts upon the amino acid histidine, which is naturally present in the dairy protein, converting it into histamine. The chemical reaction involves the removal of a carboxyl group from the histidine molecule, resulting in the formation of histamine, which raises the histamine content of the final product.
The concentration of histamine in the finished sour cream can vary based on several factors, including the specific strains of bacteria used in the culture, the temperature of the fermentation, and the duration of the aging process. Generally, all fermented dairy products, including yogurt and aged cheeses, contain higher levels of biogenic amines compared to their fresh counterparts like pasteurized milk. The longer the bacteria are active and the longer the product is stored, the greater the potential for histamine accumulation.
Dairy Alternatives for a Low-Histamine Diet
Since sour cream is a fermented product, it is typically restricted or avoided on a low-histamine diet. The general principle for managing dairy in this context is that freshness is the main determinant of low histamine content. Fresh, unfermented dairy products, such as pasteurized milk, butter, and cream, are usually tolerated better because they have not undergone the microbial conversion of histidine into histamine.
Specific types of cheese, such as fresh ricotta or cottage cheese that is not made with cultures, are generally considered lower in histamine than aged or hard cheeses like cheddar or Parmesan. When considering dairy-based substitutes for sour cream, alternatives like fresh cottage cheese blended with a small amount of milk and white vinegar can mimic the texture and tanginess without the histamine-producing fermentation.
For a non-dairy substitution that replicates the creamy texture of sour cream, options that have not been fermented are the best choice. Coconut cream can serve as a base for a low-histamine topping when combined with an acid like lemon juice or white vinegar to achieve a similar tartness. Plant-based creams made from rice or certain non-fermented nuts may also be used. When selecting any substitute, check the ingredient list for other fermented items or highly processed additives.