Can food allergies develop in adulthood?

Yes, food allergies can develop in adulthood, even if a person did not have them in childhood. While some children may outgrow their food allergies as they age, adults can also develop new allergies to certain foods. For example, Alpha-gal syndrome is a type of food allergy that can develop in adulthood following a tick bite, leading to an allergic reaction when consuming red meat or other products containing alpha-gal [2].

What factors increase the risk of developing food allergies in adulthood?

Several factors may increase the likelihood of developing food allergies as an adult. These factors include having other conditions such as eczema (which causes inflammation, redness, and irritation of the skin), asthma, or other types of allergies, such as hay fever. Genetics also play a role, as a person is more likely to develop a food allergy if a family member has allergies, asthma, or eczema [1].

Symptoms of food allergies in adults

Food allergy symptoms typically appear within minutes to two hours after eating the offending food, and symptoms can vary from person to person, and even in the same person each time they consume the trigger food. Common symptoms may include [1]:

• Hives (red, itchy skin rash).
• Skin redness or rash.
• Tingling or itching in the mouth.
• Swelling of the face, tongue, or lips.
• Vomiting and/or diarrhea.
• Abdominal cramps.
• Coughing or wheezing.
• Dizziness and/or lightheadedness.
• Swelling of the throat and vocal cords.
• Difficulty breathing.

In rare cases, food allergies can cause a severe, life-threatening allergic reaction called anaphylaxis. This may start with mild symptoms and then worsen to include tightening of the airways in the lungs, severe difficulty breathing due to throat swelling, a sharp drop in blood pressure and shock, and loss of consciousness. This is a medical emergency that requires immediate attention [1].

Diagnosing food allergies

To determine if you have a food allergy, your healthcare provider will inquire about your symptoms, family health history, and personal medical history, including any other allergies. They will likely perform a physical examination and may order food allergy tests. These tests can include skin prick tests, blood tests, an elimination diet, and/or an oral food challenge. The oral food challenge is considered the most accurate way to diagnose a food allergy [1].

Managing food allergies and emergency planning

There is no cure for food allergies, and the only way to prevent a reaction is to avoid consuming the food that caused the allergy [1]. If you are diagnosed with a food allergy, it is important to work with your healthcare provider to create a plan to manage your condition. This may include:

• Avoiding triggers: Identifying allergenic foods and avoiding them strictly.
• Reading labels: Reading food labels carefully to avoid allergenic ingredients.
• Epinephrine auto-injector: If you are at risk for anaphylaxis, your doctor may prescribe an epinephrine auto-injector. It is essential to learn how to use it and carry it with you at all times [1].
• Medical bracelet: Wearing a medical alert bracelet that identifies your allergy can be helpful [1].

In the event of anaphylaxis symptoms, such as severe difficulty breathing, throat swelling, or low blood pressure, you must seek emergency medical help immediately [1]. For more information on this topic, you can visit Adult Food Allergy: Diagnosis, Avoidance, and Emergency Plan (Arabic).

Medical references

• Food Allergy
• About Alpha-gal Syndrome