Food Allergy vs. Food Intolerance: What’s the Difference?

The difference between a food intolerance and food allergies can be confusing.

Find out what causes symptoms, what symptoms look like, diagnostic processes, and how allergy drop immunotherapy can treat the cause of food allergy.

What is a food intolerance?

A food intolerance can occur from a variety of causes including a missing enzyme needed to digest food, irritable bowel syndrome (IBS), food poisoning, or food additive sensitivity. Dairy, gluten, and foods that can lead to gas buildup such as cabbage and beans are foods that commonly cause food intolerance symptoms.

A common example of a food intolerance you’ve probably heard of is lactose intolerance. Symptoms occur when your body is missing lactase, an enzyme needed to digest lactose. Without the enzyme, your body can’t fully digest the lactose you eat or drink, which can trigger uncomfortable symptoms.

Food Intolerance Symptoms

Food intolerance symptoms may not appear for several hours, or days, and may also take a couple days to go away:

  • Stomach pain
  • Gas, cramps, or bloating
  • Heartburn
  • Nausea or vomiting

The biggest difference between food intolerance and food allergy symptoms is their severity. Food intolerance symptoms are generally less serious, typically causing discomfort in the digestive system. However, food allergy has the potential to impact multiple body systems and may cause mild to life-threatening reactions.

What is a food allergy?

During a food allergic reaction, your immune system mistakes certain foods as “threats.” In response, your body produces Immunoglobulin E (IgE) antibodies to fight off the intruder causing allergic symptoms.

Food Allergy Symptoms

Food allergy symptoms typically occur within two hours of ingesting or being exposed to the problem food.

Less severe food allergy symptoms:

  • Hives
  • Eczema
  • Headache
  • Mouth itching
  • Runny nose or congestion
  • Upset stomach
  • Fatigue

More severe anaphylactic symptoms may include:

  • Obstructive swelling in mouth and throat
  • Trouble swallowing
  • Loss of consciousness
  • Drop in blood pressure

The potential for life-threatening food allergy symptoms stresses the importance of knowing the difference between a food allergy and food intolerance.

Many times, allergic reactions are inconsistent, and when food intolerance is assumed, it can lead to being under prepared for the danger of a more severe allergic reaction. Just because you may have a mild allergic reaction to a food one time, doesn’t mean the symptoms will only be mild next time – in fact, the next reaction could be life-threatening.

Diagnosing a Food Allergy or Food Intolerance

Because food intolerance and food allergy symptoms overlap, it can be difficult to make the proper diagnosis. Doctors often look at the pattern of a patient’s symptoms by having them use a food diary or an elimination diet to determine what food is causing the intolerance, and then avoid the food(s) that are creating the intolerance.

Doctors may also conduct blood tests to measure the antibodies or IgE levels in the blood and conduct skin prick testing to identify any food allergies. In some cases, an oral food challenge may be conducted. With food allergy symptoms that are severe, always carrying an epinephrine pen has the potential to save a life.


Treating the Cause of Food Allergy with Sublingual Immunotherapy

Because avoidance strategies may not be possible, immunotherapy in the form of sublingual immunotherapy (SLIT), or allergy drops, may be a safe and effective treatment option for those who live with food allergies.

Many food-allergic patients find allergy drops helpful for building tolerance in case of accidental exposure to reduce the possibility of a life-threatening reaction. For some, treatment may even lead to the possibility of reintroducing problem foods into the diet.

Allergychoices advocates personalized allergy drops following the La Crosse Method™ Protocol which is a safe option to consider. Dosing is personalized for your specific allergies to help your body build tolerance, while minimizing unnecessary reactions. Find a provider near you who can help you start the journey of modifying your allergies.


Editor’s Note: This post was originally published in 11/20/2016 and has been revamped and updated for accuracy and comprehensiveness.