Can You Be Allergic or Sensitive to Citric Acid?

A sensitivity to citric acid (found in citrus fruit) is very rare, and it is not actually an allergy. Citric acid is a simple molecule, and the body doesn't produce an antibody to it that would trigger an allergic reaction or show up in a traditional allergy skin test.

However, it's entirely possible that the citric acid in food might trigger some form of sensitivity in certain people.

Food Allergy Symptoms

You might be having a food allergy reaction if you have the following symptoms:

• Itching of mouth, tongue and lips and rashes around mouth
• Gastrointestinal symptoms, such as abdominal pain, bloating, or diarrhea
• Swelling of the mouth or throat
• Headaches
• Other symptoms of food allergy

These symptoms can be triggered by many different types of food, but they are not usually part of sensitivity to citric acid.

Citric Acid Reactions

You can experience symptoms that aren't associated with an allergy after eating citrus fruit:

• Mouth sores
• Heartburn
• Aggravation of acid reflux symptoms

Natural vs. Synthetic

Citric acid in its natural form is extracted from fruits. People who react to fruit-derived citric acid actually are allergic to the fruit, not to citric acid itself.

Citric acid can also be synthesized commercially.

If you're sensitive to the fruit or to substances from the synthetic process, those may be what's triggering your reaction.

Sources of Citric Acid

Citric acid derived from natural sources has been used as a food additive for over 100 years. It's often used to provide a sour or tart flavoring, act as a preservative, or serve as an emulsifier. It's also commonly added to canned and jarred foods to prevent botulism.

Citric acid is found in foods including:

• Ice cream
• Sorbet
• Caramel
• Soda
• Beer
• Wine
• Baked goods
• Processed sweets
• Pre-cut pre-packaged fruits and vegetables

It acts as a preservative in these foods and to provide a longer shelf life.

Mold or Corn Allergy

Citric acid is also synthetically produced using a type of mold called Aspergillus niger, a safe strain of black mold. It's much cheaper to produce it this way than to use the natural version.

In the manufacturing process, the mold culture is fed sugar solutions, which are often derived from corn. This is often the source of citric acid used as a food additive in many processed foods.

It's not unusual to have an allergy or a sensitivity to mold or corn, and in fact, many people who react to foods containing citric acid may actually be allergic to the mold or the corn used to produce the acid.

• If you have an allergy or sensitivity to airborne mold or mold found in the environment, you may also react to mold in or on the foods you eat.
• If you're allergic to corn, you may be sensitive to the tiny amount of corn that's left in citric acid during the manufacturing process.

An allergist can determine if you have an allergy to mold or corn by using a skin-prick test, but to determine if you're also sensitive to mold in foods, you'll need to do an elimination diet and supervised oral food challenge.