Are Onions High in Histamine?

Are onions high in histamine? It’s a question you should ask if you have histamine intolerance. Histamine intolerance is a condition where you have difficulty breaking down histamine in the body.

Histamine is a chemical involved in immune response, digestion, and nervous system function. For those with histamine intolerance, consuming foods high in histamine can trigger uncomfortable symptoms.

Common symptoms of histamine intolerance include hives or skin rashes, headaches and migraines, runny nose and congestion, digestive issues like abdominal pain and diarrhea, asthma-like symptoms, and for some even anxiety, fatigue, and irregular heartbeat. (2) The severity of symptoms can vary widely based on the individual and amount of histamine consumed.

People with histamine intolerance lack sufficient levels of the enzyme diamine oxidase (DAO) needed to properly metabolize ingested histamine. (3)  So higher histamine foods can overwhelm their system and cause immune and inflammatory reactions that lead to symptoms affecting multiple body systems.

So, on to the question: Are onions high in histamine and are they safe to enjoy on a low-histamine diet?

Histamine Levels in Onions

Onions can be tricky for people with histamine intolerance. While they’re notoriously high in histamine as aged cheeses or cured meats are, onions can still be a problem for some, depending on their specific sensitivities.

If you have a severe histamine intolerance, onions may need to go on your “no” list, even when they’re cooked. The sulfur compounds and other substances in onions can trigger reactions in people who are highly sensitive to these compounds.

If you aren’t sensitive to sulfur compounds though, onions may be okay in smaller amounts or if they’re freshly chopped right before eating.

It really comes down to knowing your own tolerance thresholds. Pay attention to how your body reacts when you eat different foods. Keep a food journal to track symptoms. That will give you the best sense of which high-histamine foods you need to avoid completely, and which you might be able to handle now and then or in moderation.

Listen to your body and adjust your diet accordingly for the most comfortable way of eating.

In my experience as a physician who has worked with people who have histamine intolerance, most people can tolerate them in modest quantities. Fortunately, it doesn’t take a lot of onion to add flavor to a salad or a pot of soup.

onions are low in biogenic amines

Do Onions Contain Other Biogenic Amines?

Histamine is one type of biogenic amine that can trigger reactions in some people, but they’re not the only ones. A variety of foods contain biogenic amines – compounds like histamine, tyramine, and cadaverine. You’ll find them in fish, meat, cheese, vegetables, wine…all sorts of eats.

For most folks these amines don’t cause issues, but some unlucky people react poorly, with symptoms like trouble breathing, rashes, vomiting, fever, or high blood pressure. It’s no fun! If you have histamine intolerance, you may also be sensitive to other biogenic amines in food. (1)

Although there isn’t a lot of research looking into the biogenic amines in onions, there’s no evidence that onions are high in these compounds, just as they’re not known to be high in histamine.

However, there are steps you should take with all produce, including onions, to prevent the build-up of histamine or other biogenic amines as the produce ages.

Handling Onions Properly on a Low-Histamine Diet

First, be gentle and avoid damaging onions when prepping them. Bruising and rough handling can allow microbes to get inside and start growing. Next, cool things down quickly. The longer produce sits at warm temperatures, the more chances there are for bacteria to multiply.

And of course, good hygiene is always important – wash hands, equipment, and surfaces often to get rid of dirt and germs.

Taking these basic steps of handling produce carefully, getting it chilled fast, and keeping things clean can really help prevent microbes from going wild and producing biogenic amines, which can make food unsafe.

Just remember to be gentle, be cool, and be clean! That’s the best way I know to keep food fresh and healthy after it’s harvested.

How to Enjoy Onions on a Low-Histamine Diet

If you love the flavor that onions add to food, they’re a smart choice from a health standpoint. Onions are low in calories but high in nutrients. They contain vitamin C, vitamin B6, folate, potassium, and antioxidants.

Onions have antibacterial properties. (4) They may help lower blood sugar, reduce heart disease risk, and promote gut health due to their anti-inflammatory compounds. (5) The antioxidants in onions can reduce oxidative stress as well. Onions also contain prebiotics that feed beneficial gut bacteria. (6)

Onions, especially yellow onions, are one of the best dietary sources of quercetin. Quercetin is a plant flavonol that has been shown to have anti-inflammatory and antihistamine properties. For those struggling with histamine intolerance, quercetin may be helpful in inhibiting the release of inflammatory histamine compounds.

Do Onions Have Anti-Inflammatory Activity That Benefits Histamine Intolerance?

Some research suggests quercetin stabilizes mast cells, preventing them from releasing histamine and other inflammatory chemicals, and has anti-inflammatory activity.(7,8) The high quercetin content in onions may aid the body’s enzymes in metabolizing histamine more effectively. This helps reduce common symptoms like rashes, digestive upset, sinus congestion, and headaches.

While more research is still needed, adding more onion and other quercetin-rich foods into your diet could support overall histamine tolerance. When preparing onions, opt for thorough cooking and pairing them with fresh herbs like parsley to maximize benefits.

Being thoughtful about portion sizes and food combinations may also allow you to reap the anti-inflammatory rewards of onions without provoking unwanted reactions. With some care and customization, onions and their unique nutrients like quercetin may be a tasty tool for taming histamine intolerance.

onions can often be tolerated on a low-histamine diet

Be Aware of Other Food Sensitivities Beyond Histamine Intolerance

Beware of onions if you have irritable bowel syndrome. If you have this common condition, foods high in FODMAPs (Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols) can aggravate the symptoms of irritable bowel syndrome. Onions is a high-FODMAP food.

If you can tolerate them, onions are a healthy vegetable that provide nutrients, fiber, and plant compounds that offer health benefits. Incorporating onions into a balanced diet can contribute to overall good health.

The best way to enjoy onions if you’re sensitive to the sulfur compounds is to eat them as a garnish rather than eating them in large quantities. Raw onions, in particular, can be hard to digest. Cooking onions will improve their digestibility. As mentioned, choose fresh onions and use them quickly.

While not the highest histamine food, onions can be a trigger for some. Monitor your individual tolerance and add them to your diet slowly.


Are onions high in histamine? Onions offer nutritional benefits but their suitability depends on individual sensitivities and preferences. Enjoying onions in moderation can allow you to savor their flavor without compromising well-being.

Overall, with mindful consumption, you may be able to enjoy onions as part of a balanced, low-histamine diet. Paying attention to personal tolerance levels and handling onions carefully can help maximize their benefits while minimizing risks.

I get how hard it can be to enjoy foods you love when you have to watch what you eat. But with onions, a little mindfulness and planning can go a long way. Instead of scarfing them down thoughtlessly, take a moment to really savor the sweet, tangy flavor.

Start paying attention to how onions make you feel – any digestive issues or inflammation? If so, try reducing your portion sizes or cooking them thoroughly to lower the histamine levels. Look up recipes to find new ways to cook with onions that don’t irritate your system.

There are so many delicious meals you can make while still being kind to your body. A few tweaks can help you continue enjoying those yummy yellow onions without the unwanted side effects. With some care and creativity, you can have your onions and eat them too!


  1. Naila, A., Flint, S., Fletcher, G., Bremer, P., & Meerdink, G. (2010). Control of Biogenic Amines in Food—Existing and Emerging Approaches. Journal of Food Science, 75, R139 – R150.
  2. Hrubisko M, Danis R, Huorka M, Wawruch M. Histamine Intolerance-The More We Know the Less We Know. A Review. Nutrients. 2021 Jun 29;13(7):2228. doi: 10.3390/nu13072228. PMID: 34209583; PMCID: PMC8308327.
  3. Manzotti G, Breda D, Di Gioacchino M, Burastero SE. Serum diamine oxidase activity in patients with histamine intolerance. Int J Immunopathol Pharmacol. 2016 Mar;29(1):105-11. doi: 10.1177/0394632015617170. Epub 2015 Nov 16. PMID: 26574488; PMCID: PMC5806734.
  4. Ahmed, Mr, Ahmed Kabrah, Hani Faidah, and A Turkistani. “Antibacterial Effect of Onion.” ResearchGate. unknown, November 30, 2016.
  5. Zhao XX, Lin FJ, Li H, Li HB, Wu DT, Geng F, Ma W, Wang Y, Miao BH, Gan RY. Recent Advances in Bioactive Compounds, Health Functions, and Safety Concerns of Onion (Allium cepa L.). Front Nutr. 2021 Jul 22;8:669805. doi: 10.3389/fnut.2021.669805. PMID: 34368207; PMCID: PMC8339303.
  6. ‌Carlson JL, Erickson JM, Lloyd BB, Slavin JL. Health Effects and Sources of Prebiotic Dietary Fiber. Curr Dev Nutr. 2018 Jan 29;2(3):nzy005. doi: 10.1093/cdn/nzy005. PMID: 30019028; PMCID: PMC6041804.
  7. Jippo T, Kobayashi Y, Kousuke Kitada, Koji Kitsuda. Anti-allergic activity of an ethanol extract of bunching onion (Allium fistulosum), a traditional vegetable from Osaka. Functional Foods in Health and Disease. 2022;12(3):128-128. doi:
  8. Li J, Sun Z, Luo G, et al. Quercetin Attenuates Trauma-Induced Heterotopic Ossification by Tuning Immune Cell Infiltration and Related Inflammatory Insult. Frontiers in Immunology. 2021;12.

Hi! I'm Dr. Kristie Leong M.D. M.S. I graduated from Virginia Commonwealth University and have a deep interest and passion for histamine intolerance. My journey includes a comprehensive Kindle ebook on Histamine Intolerance and its dietary management.With a Masters in Clinical Pathology, my knowledge of immunology adds a robust scientific foundation to my expertise. I wholeheartedly believe in the power of lifestyle and prevention in healthcare. Let's work together to manage histamine intolerance through practical dietary and lifestyle choices. :-)