Food is designed to nourish the body, but with food allergies and intolerances, food can be harmful with potentially severe reactions. It is reported 15 to 20 percent of the population have a food intolerance, and an estimated 32 million Americans suffer from food allergies, or one in 10 adults and one in 13 children. 

Both food intolerances and allergies can result in discomfort and various side effects. However, there are some lifesaving distinctions between intolerances and allergies.

How do food intolerances and allergies differ? Find out all you need to know for commonalities, differences, and treatments between food intolerances and allergies. 

What Is Food Intolerance?

A food intolerance, or food sensitivity, is predominately when the body lacks key enzymes to properly digest a food component. An intolerance mainly affects the digestive system. 

In the case of lactose intolerance, the enzyme lactase is deficient and unable to break down lactose, the sugar found in milk, which causes unpleasant digestive symptoms. Gluten intolerance is another example. As while one might not test positive for celiac disease, they may experience related symptoms and benefit from a gluten-free diet. 

Chemicals added to foods could also produce a food intolerance. For example, sulfites in wines or compounds added to food to enhance flavor, like monosodium glutamate (MSG), can be food intolerances for some people.

The amount of food eaten is related to how severe the symptoms will be. People with food intolerances may have no to little amount of symptoms if only a small amount of food is eaten. Those with gastrointestinal disorders, such as irritable bowel syndrome, are more likely to also have various food intolerances.

Food Intolerance Symptoms

The most common symptoms of food intolerances include:

• Nausea
• Stomach pain
• Gas, cramps, or bloating
• Vomiting
• Heartburn
• Diarrhea
• Headaches
• Irritability or nervousness

Food intolerance symptoms may develop immediately or several hours or days after eating.

How Food Allergies Are Different than Food Intolerances

Unlike a food intolerance, an allergy involves the immune system which identifies a food protein as an allergen, produces antibodies called Immunoglobulin E (IgE), and triggers an immune reaction. Because the immune system is involved with an allergy, food allergy symptoms can be more widespread and potentially dangerous.

An allergy is not a result of a deficiency of digestive enzymes, as the food is able to be broken down. However, the food produces an immune response that causes symptoms that can be all over the body.

Unlike a food intolerance, tiny, microscopic amounts of food can cause an allergic reaction. Food allergies can occur in childhood or as an adult, and in some instances, allergies can be outgrown.

Food Allergy Symptoms

Some symptoms of food allergies are the same as intolerances. However, there are other serious symptoms of food allergies that could be life-threatening such as: 

• Rash or hives
• Nausea
• Cramping stomach pain
• Diarrhea
• Itchy skin
• Shortness of breath
• Chest pain
• Swelling of the airways to the lungs
• Anaphylaxis (blood pressure drops dangerously low and/or airways narrow)

Allergic symptoms can develop minutes after eating, especially severe reactions. If any severe reactions develop, it is important to dial 911 immediately. If the food allergy is known to cause anaphylaxis, the allergic person may have an epinephrine pen that may need to be administered to reverse symptoms.

Common Food Allergies & Intolerances

Food allergies and intolerances can be from any food, but the type of foods below are the most common causes for either:

• Lactose or casein protein (both from dairy)
• Gluten 
• Eggs 
• Soy products
• Fish and shellfish
• Peanuts or tree nuts 
• Sulfites (mainly from wine and usually just considered an intolerance)
• Some food additives, such as monosodium glutamate (MSG) (mainly food intolerance)

Treatment & Diagnosis for Food Intolerances and Allergies

If you speculate you or your child may have a food allergy or intolerance, it is critical to consult with an allergist to safeguard the risk of inducing anaphylactic shock.

Under careful supervision, the healthcare professional will then likely conduct a series of skin, oral, and blood tests to make an informed decision on whether or not you can safely introduce such food back into the diet. It is not recommended to try this outside the guidance of an allergist.

A dietitian or doctor can also help guide the steps for an elimination diet to assess which foods may be the root for allergy or intolerance symptoms. This involves eliminating suspected foods from the diet then reintroducing them back gradually to assess if symptoms appear and should only be done with the recommendation of the healthcare team first.

Treating both food intolerances and allergies is the same: eliminating foods from the diet. Depending on the severity of an intolerance, small amounts of problematic food may be tolerated or medicated.

Overall, it is important to get educated about hidden sources of any food allergens/intolerances and to read food labels thoroughly. If desiring convenient meals without added stress, trust in an allergen-safe meal delivery service that takes food and allergy preparation very seriously. 

Recap: Food Allergies vs Food Intolerances

Both food intolerances and allergies are fairly prevalent. Food intolerances are generally from trouble digesting or absorbing a certain food and mainly cause gastrointestinal distress. Even though this is uncomfortable, it is not life-threatening. 

Food allergies, on the other hand, involve an immune response from proteins in the food and have the potential to cause life-threatening reactions such as anaphylaxis, shortness of breath, or closure of airways. 

Any food could cause an allergic or intolerance response, but there are certain foods that cause the most intolerance or allergic reactions. They include dairy, eggs, soy, peanuts, tree nuts, fish/shellfish, and sulfites or other food additives for food intolerances.

If food allergies or intolerances are suspected, it is recommended to work with an allergist and your healthcare team to assess the best procedures for testing. These trained professionals can also help guide through an elimination diet, if necessary, to determine foods that are causing adverse reactions.

References:

Food Allergy vs. Food Intolerance: Symptoms, Causes & Prevention. Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/10009-food-problems-is-it-an-allergy-or-intolerance.