While onions are a staple in most cooked food and cuisines, you may not be aware of the possibility of an onion allergy. Almost all of your home-cooked meals and even the packaged foods typically contain onions and garlic. From soups to savory pies, everything calls for onions. It imparts a prominent sweet and umami flavor to the food.
For many, raw onions are their favourite addition to salads and omelettes. With the role it has in every dish, it is nearly impossible to avoid – even if you are intolerant to onions. Some people only experience an allergic reaction to raw onions. While others are super sensitive when exposed to both raw and cooked onions. Even touching and the distinctive smell of onions can make them sick.
Why are you allergic to onions?
Food allergies are your body’s hypersensitive reaction to certain foods. For instance, dairy and peanut allergies are most common. Although the cause of such food allergies is unclear, it is the aversion of your immune system to certain foods. However, experiencing a true allergy to onions is rare.
Onion and garlic belong to the family Amaryllidaceae (genus: Allium). If you are sensitive to these, you may experience allergic reactions to other alliums as well (like shallots). Sometimes, inedible alliums can also trigger your sensitivity reactions. Studies show that people show allergic symptoms because of the diallyl disulphide component of onions.
When you consume raw or cooked onions, your immune system detects them as a harmful substance. This leads to the release of Immunoglobulin E antibodies into your bloodstream. It fights against the threat of proteins in onions and garlic. As a result, mast cells in your body produce histamine, which causes inflammation in tissues.
Onion allergy vs onion intolerance
Again, you rarely experience a true allergy to onions. Often, what you see are food intolerances. If you are sensitive to onions, you show signs of digestive problems—less severe and easily prevented. However, if you are allergic to onions, your immune system gets activated, which results in symptoms that can be mild to even life-threatening.
Since allergy and intolerance have similar symptoms, people often get confused between the two. So, what are the symptoms of allergy and intolerance to onions?
While food intolerances are usually self-diagnosable, you need medical advice for any signs of serious reactions. Some commonly experienced symptoms are bloating, cramps, belching, gas, stomach pain, and restlessness.
If you experience symptoms like difficulty breathing, chest tightness, rashes, hives, wheezing, facial swelling, abdominal pain, vomiting, and nausea, chances are you have an allergic reaction to onions. More severe symptoms like metallic taste in your mouth, increased heart rate, drop in blood pressure, dizziness, and swelling of your lips, need urgent care from a health professional. This could be a sign of a severe anaphylactic reaction, which is life-threatening.
What are the foods to look for that cause allergy?
Since most culinary items contain onion and garlic as ingredients, it’s challenging to avoid them completely. But if you are allergic to onions, you may react to plants, food, and substances that include similar proteins- known as cross-reactivity. Therefore, you need to avoid foods that contain other edible alliums such as shallots, chives, garlic, and scallion.
Often, the packaged and processed foods you buy contain onions too. For instance, salsa, frozen crust, instant soups, sauces, tuna salad, chicken, and vegetable broth— contains onion and garlic powder as a base ingredient. You need to check the labels for ingredients before buying them – often they are labelled as seasonings. If you are hesitant, contact the manufacturer for details.
If you are allergic to alliums, you might be reactive to other inedible ornamental alliums as well. Even touching and smelling such allergens can cause reactions. Some flowering plants you need to avoid include wild onions, wild chives, rock onions, tiger lily, tulips, and daffodils. This can cause itchiness, rashes, and other allergic symptoms.
Can you treat and prevent your onion allergy?
The answer is yes! You can treat your allergic reactions to onions based on their severity. As soon as you experience the symptoms after you ingest onions, take an over-the-counter antihistamine medication. It helps to relieve minor symptoms like itching, hives, and inflammation as it blocks the action of histamine.
A simple over-the-counter hydrocortisone cream can help reduce your skin itching. You can also use aloe vera gel to soothe the redness associated with itching. As it is cooling in nature, it helps to reduce inflammation as well.
If you develop more severe cases of allergy such as anaphylaxis, you need to take epinephrine (EpiPen) – a prescription medication. Always seek medical attention if you experience this. If left untreated, this can even be fatal.
The most effective way to prevent these onion-related symptoms is to avoid them altogether. Of course, it is challenging. But it will keep you from developing any allergy symptoms.
For some, cooked onions are not a threat. As you cook onions, it reduces the compounds in them to which you are allergic. Also, stop eating other edible alliums which can trigger your allergy symptoms.
Are there any onion substitutes with a similar flavour?
Yes! In case you are allergic or sensitive to onions, you can try some alternatives. Undoubtedly, onions make a meal more savoury because of their distinct flavour. Many cuisines around the world rely on onions and garlic as vital ingredients. If you are looking for onion substitutes that have similar flavour and texture, below are some simple vegetables that can come in handy.
- Shallot, leek, and scallion make a wonderful substitute for onions. But you need to stop consuming them if you are allergic to alliums.
- Celery is another backup for onions, which has a similar crunchy texture in raw form. You can prepare stews and soups with it.
- Even fennel has an oniony flavour and is liquorice-scented. It can be tasty and irresistible when cooked in soups.
- Asafoetida (also known as Hing) has a savory and pungent taste like onion and garlic. You can start with a small amount and adjust the flavor as you cook.
- Other substitutes which have similar textures include carrots, cabbage, and radish. Even collard greens and bell peppers taste yummy!
Diagnosis of an onion allergy
As soon as you experience any allergic symptoms, consult a health practitioner for medical advice. A physical examination by an allergist helps to determine if you have food allergies.
Apart from these, you can try an elimination diet to see if the onions are causing your allergies. You can practice this restrictive diet for about five to six weeks. You have to eliminate foods you are allergic to and gradually reintroduce them one by one. It helps to determine which one is causing allergic reactions.
The diagnostic tests can pinpoint whether you have a food allergy or sensitivity. Most commonly, you have to do blood tests to see the levels of your Immunoglobulin E antibodies. This helps to determine the cause of your allergy.
Furthermore, a skin test is helpful to identify allergies —in which an allergist injects a small amount of an allergen into your skin. If you develop any kind of reaction like itchiness and hives, it shows you are allergic to it.
Whether you have an onion allergy or sensitivity, it is necessary to take preventative measures. If raw onions cause your allergy, you should always choose cooked onions. Some onion substitutes are also worth a try. A mild-to-moderate reaction is usually self-treatable. However, remember to seek medical advice if you accidentally eat onions and develop potentially dangerous allergic symptoms.