For those with known food allergies, it can be frustrating to have to continuously avoid the types of food that are triggering these reactions — especially if you’ve always had cravings for these. It can also be aggravating to constantly ask whether a dish you're about to eat contains the foods that are causing your allergies.

What is a food allergy?

A food allergy occurs when your immune system reacts abnormally to anything you eat or drink. Food allergies can cause problems with the skin, gastrointestinal tract, cardiovascular and respiratory systems. 

These food allergies are most common in children. They usually outgrow them, though this is not always the case. People can develop food allergies in adulthood as well, but this is also a rare occurrence.

Food allergens can come in many forms, but some foods are far more likely to cause an allergic reaction than others. According to Food Allergy Research and Education (FARE), there are over 170 items that have been linked to allergy responses. However, the following are the types of foods that cause about 90% of all food allergies:

• eggs
• milk
• tree nuts
• peanuts
• fish
• crustacean shellfish
• soy
• wheat

What are the symptoms?

Food allergies can cause mild to severe symptoms. They might appear quickly or develop after a few hours. The mild symptoms of a food allergy include stomach cramps, diarrhea, sneezing, stuffy or runny nose, itchy or watery eyes, swelling, and rashes.

On the other hand, symptoms of a severe food allergic reaction are difficulty breathing (can also be wheezing), swelling of the throat, lips, or tongue, hives, nausea, or dizziness. Food allergies can be particularly hazardous and life-threatening, especially if breathing is impacted. Because of this, people with asthma are more likely to have a deadly allergic reaction to food and should take more precautions.

Diagnosis

Food allergies are often diagnosed based on the severity of their symptoms.

People with mild symptoms are usually asked to keep a food diary to record everything they eat or drink in order to narrow down the culprit. Another technique for diagnosing a mild food allergy is to eliminate specific items from the diet and then gradually reintroduce them to determine if symptoms reappear. 

In cases wherein the symptoms are severe, a skin or blood test can be used to determine whether an individual is allergic to milk, nuts, eggs, or shellfish.

Treatment

There is no known cure yet for food allergies. Nonetheless, the reactions could be managed by avoiding the offending food(s) and learning to identify and treat the symptoms of the allergy. For the people who have these allergies, this is critical in order to prevent serious adverse health effects.

For mild symptoms, these may not require treatment at all — or they may be resolved with the use of an over-the-counter antihistamine. For the more serious symptoms, a doctor may need to prescribe steroids. Because steroid medications have the potential for major adverse effects, these should not be used for longer than a few days at a time.

If you have a known food allergy and start developing allergic symptoms, discontinue eating the food immediately. Determine the necessity of emergency treatment (such as epinephrine) and seek medical assistance.