Amines are natural chemicals that bacteria create in food as it ages, ferments or sits in storage, by breaking down the protein the food contains. A few of them can act on blood vessels and nerves if they arrive faster than the body clears them. Histamine is the best known, and it has its own guide covering histamine intolerance in full. This guide covers the wider family, tyramine above all, along with phenylethylamine, putrescine, cadaverine and the polyamines. It explains where amines come from, which foods carry the most, what symptoms the evidence does and does not link to them, and why tyramine needs particular care with one group of antidepressant medicines.
Where amines come from
Amines form when bacteria break down protein. Each one starts as an amino acid, one of protein's building blocks, and a bacterial enzyme strips part of the acid away, leaving the amine behind. Histidine becomes histamine, tyrosine becomes tyramine, and the same step turns other amino acids into phenylethylamine, best known from chocolate, tryptamine, and the bluntly named putrescine and cadaverine. A 2016 review of amines in food names these, together with the polyamines spermidine and spermine, as the amines that matter most in what we eat, and the bacteria that make them are the ordinary ones that ripen cheese, cure meat and ferment vegetables, as well as the ones that spoil food kept too long. Chemical reactions like these are one of the ways a food intolerance can arise. The other main routes, enzyme shortfalls and fermentable carbohydrates, work through digestion instead.
Histamine attracts most of the attention because the body also uses it as a signalling chemical, so histamine from food lands on systems that already run on it. The relatives travel in the same foods but behave differently once eaten. Tyramine can push blood pressure up if it reaches the bloodstream in quantity, which is why it matters so much alongside one class of medicines. The polyamines sit at the other end of the scale. A 2019 review describes putrescine, spermidine and spermine as ordinary components of almost every food, involved in cell growth and in the development of the gut, and studied mainly for possible benefits rather than for harm.
Which foods carry the most amines?
Age and fermentation raise amine levels more than any ingredient does. Fresh meat, fresh fish, fresh vegetables and fresh dairy are all low in amines. Give bacteria protein and time, and levels climb, which is why the foods most often named are matured cheeses, cured and fermented meats such as salami, fermented vegetables and soy products, fish that has been stored rather than eaten fresh, and beer, wine and yeast extract.
Cheese shows the pattern most clearly. A 2026 systematic review of cheese ripening found that tyramine and histamine were the two amines most often reported at high levels, with concentrations building over months of maturation and varying with how each cheese was made and stored. Long-aged varieties generally carry more than young, mild ones. Once amines have formed, cooking does not remove them, so ageing cannot be undone in the kitchen.
Two things follow from that chemistry. Amine-rich food lists overlap almost completely with high-histamine food lists, because the same bacteria make several amines side by side, and a food high in one is usually high in others. And the numbers on any list are estimates. The tyramine in a particular piece of cheese depends on how it was made, how long it was aged and how it was kept, which is part of why reactions to these foods can seem inconsistent from one week to the next.
How your body clears amines
Two enzyme systems stand between the amines in a meal and your bloodstream. Monoamine oxidase, or MAO, works in the gut wall and liver and breaks down tyramine and phenylethylamine as they are absorbed. Diamine oxidase, or DAO, works in the gut lining on histamine, putrescine and cadaverine. In most people both systems have capacity to spare, which is why a cheese board followed by red wine, one of the larger amine loads an ordinary evening can deliver, usually passes without any effect at all. According to a 2022 review of MAOI drug interactions, with MAO working normally, tyramine from food is broken down before it can build up to levels that affect blood pressure. Most of the open questions in this field concern what happens when one of these enzymes runs slow. For DAO and histamine, we cover that story separately.
Tyramine and MAOI antidepressants
A small group of antidepressants called monoamine oxidase inhibitors, or MAOIs, work by blocking the MAO enzyme, and the older ones, such as phenelzine and tranylcypromine, block it in the gut wall and liver as well as in the brain. With that barrier down, tyramine from food is absorbed intact, and tyramine in the bloodstream drives blood pressure up sharply. A 2012 review of MAOI food and drug interactions describes the result, a hypertensive crisis, as rare but dangerous, and it is the reason dietary guidance comes with every MAOI prescription. The 2022 review above adds the scale. Once MAO is blocked, as little as 8 to 10 milligrams of tyramine can be enough to affect blood pressure, and aged cheeses and cured meats are the foods most likely to supply it.
The interaction came to light when people taking the first antidepressants of this type became suddenly and severely unwell after aged cheese, which is why it is still sometimes called the cheese reaction. It applies to people taking an MAOI and to no one else. With the enzyme working, the same cheese board does nothing of the kind. Anyone prescribed an MAOI is given dietary guidance alongside it, and that guidance is the version to follow rather than any list found online, because newer MAOIs differ in how completely they block the enzyme and the advice is matched to the specific medicine. Never stop or change an antidepressant, or any other prescribed medicine, over something you have read about food. If you take an MAOI and are unsure about a particular food, ask your pharmacist, who can check it against your actual prescription.
Can amines cause headaches and other symptoms?
Tyramine has sat on lists of suspected migraine triggers for decades, alongside the aged cheese, chocolate and red wine that carry it and its relatives. A 2025 review of diet and migraine keeps it there, naming tyramine among the foods and ingredients that can set off attacks in people who are susceptible to them, while noting that triggers differ widely from one person to the next. The wider evidence is softer than the tradition suggests. A 2016 review of diet and headache ranked caffeine withdrawal and monosodium glutamate as the triggers with the strongest evidence, while the support for histamine-containing foods and alcohol rests on observational studies, the kind that record a pattern without being able to prove the food caused it.
For gut symptoms, the research runs thinner still. When a 2024 systematic review pulled together 21 studies of diets that restrict natural food chemicals, amines included, it could not draw firm conclusions for gut symptoms, because the trials were few and inconsistent, and its strongest findings involved skin rather than digestion. An amine sensitivity beyond histamine is, for now, a pattern people notice rather than a condition medicine can confirm.
Working out whether amines sit behind your own symptoms therefore rests on the pattern. Symptoms that follow aged, fermented or long-stored foods across several food groups fit the amine question. Symptoms that follow one food, fresh or aged, point at the food itself. Reactions that bring hives, swelling or any change in breathing are a different matter entirely, because those signs raise the difference between a food allergy and an intolerance, and allergy belongs with your GP, not a food diary. Headaches, tiredness and gut upset that track meals also belong to the broader set of symptoms a food intolerance can cause, which more than one mechanism can produce.
What can a food intolerance test show?
No consumer test measures the enzymes that clear amines. Nothing you can buy measures how well the MAO in your gut wall is working, and no test of any kind is validated to diagnose an amine intolerance, ours included.
What an IgG panel shows is different and specific. Our at-home IgG food intolerance test checks your IgG antibody levels against 270 individual foods and drinks, and the foods that dominate amine lists, matured cheeses, cured meats, fermented foods and fish among them, are each tested in their own right. An elevated result for one of them may indicate a food sensitivity to that particular food, an immune response to the food itself rather than a reaction to its amine content. That distinction is most useful in one situation. If one aged food keeps causing trouble while other amine-rich foods cause none, shared chemistry stops being a convincing explanation, and the better question is whether your body is reacting to that food specifically. When our clinical team interprets results, that is the line they read them against, because an immune response to one named food and a chemical shared by a whole shelf of foods point to different next steps.
Do you need to avoid amine-rich foods?
Not without a reason. Amines are part of eating, the polyamines are part of normal cell chemistry, and matured and fermented foods bring protein, calcium and live cultures along with their amines. Someone with no symptoms gains nothing by cutting them out.
Where aged and fermented foods do keep producing symptoms, a short, structured reduction followed by deliberately reintroducing the foods shows whether the pattern is real, and it is best run with our clinical team or a registered dietitian, so nothing is cut without a plan for its return. Improvement while avoiding a food proves little until the food comes back and the symptoms return with it. The NHS pathway for suspected food intolerance works the same way, through a GP and a dietitian rather than open-ended restriction. Freshness is the cheaper lever. Buying fresh, eating food sooner, keeping it cold and not letting leftovers linger all lower the amine content of the same meals without removing a single food. If restricting what you eat has ever felt hard to control, involve your GP or a dietitian before you change anything.
When should you see a GP?
Flushing, palpitations, headaches and stomach upset all have causes that have nothing to do with food, so some symptoms need a GP before any food experiment starts. Flushing or palpitations that keep returning need their non-food causes ruled out first. A sudden, very severe headache, a headache unlike any you have had before, or a headache that comes with weakness, slurred speech or changes to your vision is a 999 call, not a food question. Swelling of the lips, tongue or throat, widespread hives or difficulty breathing after eating is treated as an allergic emergency. Call 999.
For gut symptoms, book a GP appointment before changing your diet if you notice blood when you go to the toilet, weight loss you cannot explain, bowels that have behaved differently for more than three weeks, vomiting that will not settle, trouble swallowing, the washed-out tiredness of iron-deficiency anaemia, digestive symptoms appearing for the first time after 50, or close relatives who have had bowel or ovarian cancer. And children's diets are never restricted at home. A suspected food reaction in a child goes to a GP or health visitor first, every time.
This guide is for information only and does not replace medical advice. Speak to your GP or pharmacist about your own symptoms.
Sources
- Gardini F, Özogul Y, Suzzi G, Tabanelli G, Özogul F (2016). Technological Factors Affecting Biogenic Amine Content in Foods: A Review. Frontiers in Microbiology. PubMed | DOI
- Tashi F, Taghizadeh M, Afshari A (2026). Microorganisms and Physicochemical Factors Controlling Biogenic Amines During Cheese Ripening: A Systematic Review. Journal of Food Protection. PubMed | DOI
- Muñoz-Esparza NC, Latorre-Moratalla ML, Comas-Basté O, et al. (2019). Polyamines in Food. Frontiers in Nutrition. PubMed | DOI
- Edinoff AN, Swinford CR, Odisho AS, et al. (2022). Clinically Relevant Drug Interactions with Monoamine Oxidase Inhibitors. Health Psychology Research. PubMed | DOI
- Flockhart DA (2012). Dietary restrictions and drug interactions with monoamine oxidase inhibitors: an update. The Journal of Clinical Psychiatry. PubMed | DOI
- Tu YH, Chang CM, Yang CC, et al. (2025). Dietary Patterns and Migraine: Insights and Impact. Nutrients. PubMed | DOI
- Martin VT, Vij B (2016). Diet and Headache: Part 1. Headache. PubMed | DOI
- Cooke Z, Lynam K, Tuck C, Trakman GL (2024). Naturally Occurring Food Chemical Components and Extraintestinal and Gastrointestinal Symptoms in Adults: A Systematic Review. Clinical and Experimental Allergy. PubMed | DOI
- NHS. Food intolerance. nhs.uk
