Understanding how histamine develops in food and the limitation of the food lists, will help you navigate the low histamine diet.
If you are looking for practical suggestions, please read Practical Guide to the Low Histamine Diet.
This topic is not an exact science! The research on histamine levels in food was done primarily in Germany around the 1980’s. In summary, when bacteria grow in food (i.e., spoiled or fermented), histamine may form. Some fruits and vegetables are also thought to be high, especial as they ripen (or over ripen).
The current thinking is that the total quantity of diamines is more important than the histamine content alone (see below). Unfortunately, there is not a consistent method to measure histamine and other diamines. Even if good techniques were available, the histamine/diamine content is quite variable even in the same food (see below).
Histamine is a by-product of bacterial growth in food.
Certain bacteria can change histidine into histamine.
1) Bacteria that produce histidine decarboxylase
2) Right environment for bacterial growth (e.g., warm temperature and time).
3) Oxygen (the bacteria that produce histidine decarboxylase are thought to be oxygen dependent).
Bacterial growth in food may happen in two ways - food fermentation and food spoilage.
Food fermentation: During fermentation, bacteria/yeasts are intentionally added to food and allowed to multiple under very controlled conditions. Fermented foods include alcoholic beverages, aged cheese, sausages, sauerkraut, etc. High levels of histamine/diamines may develop in fermented foods. However, most food fermentation bacteria do not produce histidine decarboxylase.
Food spoilage: Unintentional contamination with bacteria leads to food spoilage. Scrombroid fish poisoning is a food borne illness that occurs from consuming fish that has not been gutted and refrigerated properly and has developed very high levels of histamine (and related compounds). It may account for up to 40% of seafood associated food-borne illnesses. Other foods, such as Swiss cheese, have been associated with this type of food-borne illness. Therefore it is also called histamine toxicity. Everyone that eats the tainted food would develop symptoms because there is more histamine than anyone would be able to breakdown. Some people may be more sensitive to histamine in food because of lower diamine oxidase enzyme levels.
Higher protein foods are likely more susceptible to histamine formation because they have a greater quantity of the amino acid, histidine.
Related Diamine compounds
When histamine forms in food, so do other diamines (e.g., cadaverine, putrescine, spermidine, etc.). The total diamine content is likely more important than the histamine content alone. Diamines are broken down by diamine oxidase enzyme in the digestive system. An elevated diamine content would reduce the availability of DAO for histamine breakdown. Unfortunately, there is not reliable, consistent laboratory method to measure diamine content.
Even if we had reliable laboratory method to measure food diamines, it would still be difficult to write accurate lists. Diamine formation depends on many factors:
- type of food
- type of bacteria the food has been exposed to
- growing conditions for the bacteria
If fifty food samples that were susceptible to diamine formation were analyzed (e.g., Swiss cheese), there would be tremendous variation.