What are amines? Exploring amine intolerance

Our food comprises many chemical substances needed for important physiological processes in the body. For most people, these naturally occurring food chemicals, called biogenic amines, are largely harmless as they are metabolised rapidly by enzymes in the body. Yet, in certain individuals, consuming food containing high amounts of amines may have harmful effects and trigger various reactions. This may be due to excessive intake, interaction with medications or from histamine release due to food sensitivities.

Another class of amines that may harm the body is the heterocyclic amines, which can be formed in food during the cooking process. 

Biogenic amines 

Biogenic amines in food belong to a class of amines formed due to the breakdown of proteins due to bacterial fermentation or food spoilage. They are most frequently found in fermented foods such as wines, beers, dairy products, meat and vegetables rich in protein.

Some of the most well-known biogenic amines in food include:

• histamine
• tyramine
• phenylethylamine

Histamine

Histamine is stored in the body in immune system cells, called mast cells, and is released in large amounts during allergic reactions. In food, histamine is found in fermented foods such as cheese, fermented soy products, sauerkraut, wine, and vinegar, as well as in spoiled fish. Some foods, such as eggplant and spinach, naturally contain high histamine levels.

Histamine intolerance

Some individuals are more susceptible to dietary histamine due to genetic deficiency of the enzyme that breaks down histamine in the body and, in some cases, because of interaction with their medications. In these individuals, even low dietary histamine content may induce symptoms such as dilation of blood vessels, skin flushing, increased heart rate, hives, digestive symptoms, headache, a fall in blood pressure and asthma symptoms.

Treating histamine intolerance

Research suggests that a low-histamine diet or antihistamines may help to reduce symptoms for some individuals; however, more research is needed. If you suspect histamine intolerance, it’s important to discuss this with your healthcare professional. 

Toxicological effects of histamine

Ingestion of decomposed fish may result in histamine fish poisoning, also known as scombroid poisoning. Some fish, such as mackerel and tuna, contain naturally high levels of the amino acid histidine in their muscle tissue. Inadequate refrigeration of fish allows the multiplication of bacteria that break down histidine and convert it into histamine, resulting in a reaction when the fish is eaten.

Preventing scombroid fish poisoning

• Refrigerate fish from the time of capture to the time it is cooked.
• Do not consume fish with a bad odour.
• Purchase fish only from reputable retail outlets.

Tyramine

Tyramine is a biogenic amine that can be found in aged cheeses (especially Camembert and cheddar), aged, pickled, or smoked meats (e.g., salami) or fish (e.g., herring), yeast extracts, beer, red wine, avocado, sauerkraut, bananas, chicken liver, eggplant, raspberries, red plums, tomato, vinegar and pickles.

Tyramine intolerance

Tyramine intolerance may be caused either by genetics or by an interaction between monoamine oxidase inhibitors (MAOIs - a class of antidepressants) and tyramine in foods. MAOIs can block the enzyme responsible for breaking down tyramine, which results in a build-up. 

Cheese reaction

The high tyramine content in cheese results from lactic acid bacteria breaking down the amino acid tyrosine in the cheese. A person taking MAOI antidepressants who eats cheese may develop side effects such as increased blood pressure or headache, known as a ‘cheese reaction’. Talk to your healthcare professional if you are concerned. 

Phenylethylamine

Phenylethylamine can be found in human brains and functions as a neurotransmitter, releasing the ‘feel-good hormones’ dopamine and serotonin. Cocoa contains many compounds, one of them being phenylethylamine.

Does chocolate cause migraine?

Some researchers have suggested that phenylethylamine in chocolate can trigger migraine; however, there is not enough data support it.

Heterocyclic amines

Heterocyclic amines are chemicals formed when meat is burnt or charred from cooking at high temperatures. Long-term exposure to heterocyclic amines may increase the risk of cancer, so the Cancer Council recommends gentler cooking methods to avoid charring. 

How can I minimise exposure to heterocyclic amines in meat?

• Limit over cooking meat at high temperatures.
• Marinate meat before cooking to prevent them from charring..
• Cut down on red and processed meats. The Australian Dietary Guidelines recommends limiting red meat and avoiding processed meats such as ham, salami, bacon, deli meats and hot dogs.

The Bottom line

Adjusting to new dietary habits may be difficult, but it can make you feel much better. If you think you may be sensitive to amines, it’s important to discuss this with your healthcare professional for individual advice. 

Related reads:

• FODMAPs sensitivity vs food intolerance: what’s the difference? 
• Is bloating a symptom of wheat intolerance? 
• 4 foods for gut health

References

1. Garcia, E. 2017. Monoamine Oxidase Inhibitor Toxicity. Emedicine. Available at: https://emedicine.medscape.com/article/815695-overview#showall
2. Gresham, C. 2015. Seafood Toxicity. Emedicine. Available at: https://emedicine.medscape.com/article/1011549-overview#showall
3. Cancer Council NSW. Red meat, processed meat and cancer. Available at: https://www.cancercouncil.com.au/1in3cancers/lifestyle-choices-and-cancer/red-meat-processed-meat-and-cancer/
4. Farhadian, A. et al., 2012. Effects of marinating on the formation of polycyclic aromatic hydrocarbons (benzo[a]pyrene, benzo[b]fluoranthene and fluoranthene) in grilled beef meat. Food Control, 28(2), pp.420–425. Available at: https://www.sciencedirect.com/science/article/pii/S0956713512002071
5. National Cancer Institute. Chemicals in Meat Cooked at High Temperatures and Cancer Risk -. Available at: https://www.cancer.gov/about-cancer/causes-prevention/risk/diet/cooked-meats-fact-sheet
6. San, I. et al., 2016. Histamine intolerance and dietary management: A complete review. Allergol Immunopathol (Madr), 44(5), pp.475–483. Available at: https://www.ncbi.nlm.nih.gov/pubmed/27590961
7. Skypala, I.J. et al., 2015. Sensitivity to food additives, vaso-active amines and salicylates: a review of the evidence. Clinical and Translational Allergy, 5(1), p.34. Available at: http://www.ctajournal.com/content/5/1/34
8. Traylor, J. (2023, June 26). Histamine toxicity. StatPearls - NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK499871/
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