What You Should Know About Cooking Oils If You Have a Food Allergy

Nearly 4% of the population and 8% of children have at least one food allergy. If you are allergic to a food, you are probably very careful to avoid it. But allergens can be hidden in processed foods too, leading to unexpected allergic reactions.

Cooking oils, which often appear in processed foods, can be a problem for people with food allergies. Even refined (purified) cooking oils can contain small traces of allergens, and the product's label doesn't always make that clear.

This article takes a closer look at the types of cooking oils that contain allergens. It also gives tips on what to look for when choosing an oil to cook with.

Vegetable Oils in Food Preparation

Vegetable oils are used to prepare many processed and pre-packaged foods. Over the years, there have been many reports of allergic reactions to these oils.

Some vegetable oils contain a mix of peanut oil, soybean oil, sunflower seed oil, corn oil, and/or palm oil. Despite this, the product label may simply read "vegetable oil."

Most vegetable oils are highly refined. In other words, when they are being processed, most of the proteins present in the crude (raw) form are removed. These proteins are what cause allergic reactions.

Peanut Oil Allergy

Peanut allergy is becoming more and more common. About 1% to 2% of the western population is allergic to them. Unfortunately, peanuts and peanut oil are often a hidden ingredient in many pre-packaged foods.

Peanut oil is used in cooking and food processing. It can be found in both crude and refined forms. You might see crude referred to as "gourmet," "cold pressed," or "raw." Refined might also be referred to as "heat processed."

A single peanut contains about 200 milligrams (mg) of protein. Most people with peanut allergy can have an allergic reaction after eating far less than that.

Peanut proteins are virtually eliminated during the refining process. But even refined peanut oil can still contain tiny traces of peanut protein. If you have an peanut allergy, you should ask your doctor if refined peanut oil is safe for you.

Soybean Oil Allergy

Allergic reactions to soybean oil are rare. However, a number of allergic reactions to the oil have been reported. In some cases, the oil was eaten in a food or medication, but it's also found in textiles. For example, one person had a severe allergic reaction (anaphylaxis) to soybean oil in their pillowcase.

Like peanut oil, crude soybean oil will have more proteins in it than refined soybean oil. Play it safe by only choosing highly refined soybean oils, and avoiding those that are crude, cold-pressed, or gourmet.

Sunflower Seed Oil Allergy

Sunflower seed allergy is not too common, but it does occur. Like the other oils, the allergic reaction is caused by proteins in crude sunflower oil. Those proteins are mostly removed during the refining process.

Nonetheless, anaphylaxis caused by small amounts of proteins in refined sunflower seed oil have been reported. In each case, the person had a very severe sunflower seed allergy.

Sesame Seed Oil Allergy

Sesame is becoming a more common food allergy in recent years, and severe allergic reactions can happen.

Sesame seed oil is different from many of the other vegetable oils. It's often used to flavor food because of its rich taste. For this reason, sesame seed oil is typically crude and contains high levels of sesame proteins.

Other Vegetable Oil Allergies

There are a number of other vegetable oils used in cooking and prepared foods. These include corn oil, safflower oil, canola oil, palm oil, palm kernel oil, and coconut oil.

Allergic reactions to these oils are relatively rare. Even so, it's best to avoid crude oils made of any substance you are allergic to. If your allergy to that substance is severe, you'll also want to talk to your doctor or allergist before using the refined form of the oil.

Keep in mind that, like sesame oil, any oil that is used to flavor food is likely sold in its crude form. That means the oil will have high amounts of the protein that causes allergic reactions.

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Summary

While shopping for cooking oils, you will likely come across oils labeled as "crude" and oils labeled as "refined." Crude oils are pure, so they contain all the proteins that are responsible for causing allergic reactions.

If you are allergic to a substance that an oil is made from, you will need to steer clear of the crude form. Some people with severe allergies will need to avoid the refined form as well, since small amounts of proteins may still be present.

If you aren't sure whether or not you should avoid the refined version too, ask your doctor or allergist.

A Word From Verywell

Having a food allergy can make simple experiences, like going out to eat, feel risky. If you are allergic to peanuts, for example, you might be used to asking the waiter to ensure no peanuts are added to your order. But on occasion, your waiter might not know what kind of oil is used to cook the meal or to add flavor. Make sure to mention that oils are a no-go for you as well. If ever you feel your waiter seems unsure, don't hesitate to ask for the manager.