Food Allergy vs. Food Intolerance

What is the Difference?

Food allergy is a serious medical condition affecting up to 15 million people in the United States, including 1 in 13 children.   A food allergy results when the immune system mistakenly targets a harmless food protein – an allergen – as a threat and attacks it.  If you have a food allergy, even a tiny amount of the offending food can cause an immediate, severe reaction. Digestive signs and symptoms may include nausea, vomiting, cramping and diarrhea. Other signs and symptoms can include a tingling mouth, hives, and swelling of the lips, face, tongue and throat. A life-threatening allergic reaction known as anaphylaxis can cause breathing trouble and dangerously low blood pressure. If you have a food allergy, you’ll need to avoid the offending food entirely.


Do you think you are suffering from a food allergy or food sensitivity issue? Want some relief?

+ Cross Back to Health Today!

If you have a food allergy, you may be at risk of a life-threatening allergic reaction (anaphylaxis) — even if past reactions have been mild. Learn how to recognize a severe allergic reaction and know what to do if one occurs. You may need to carry an emergency epinephrine shot (EpiPen, Twinject) for emergency self-treatment.  Make sure you discuss this with your doctor.

Food allergies are “IgE mediated.”  This means that your immune system produces abnormally large amounts of an antibody called immunoglobulin E — IgE for short.  IgE antibodies fight the “enemy” food allergens by releasing histamine and other chemicals, which trigger the symptoms of an allergic reaction. Although nearly any food is capable of causing an allergic reaction, only eight foods account for 90 percent of all food-allergic reactions in the United States.

These foods are:

  • Peanut

  • Tree nuts

  • Milk

  • Egg

  • Wheat

  • Soy

  • Fish

  • Shellfish


Other Allergens

While only eight foods account for approximately 90 percent of all food-allergic reactions, a person can be allergic to virtually any food. Although the list below is by no means exhaustive, allergic reactions have been reported to corn, gelatin, meat (beef, chicken, mutton, and pork), seeds (sesame, sunflower, and poppy being the most common), and spices such as caraway, coriander, garlic, and mustard.

Corn Allergy

Allergic reactions to corn are rare and a relatively small number of case reports can be found in medical literature. However, the reports do indicate that reactions to corn can be severe. Reactions to corn can occur from both raw and cooked corn. Individuals who are allergic to corn should receive individualized expert guidance from their allergists.

Meat Allergy

Allergies to meats, such as beef, chicken, mutton or pork, are also rare.  A person who is allergic to one type of meat may not need to avoid other types of meat. Heating and cooking meat can reduce the allergenicity of product.

Of special note is the newly discovered allergy to Mammalian Meat (i.e. Beef, Pork, Lamb, Venison, etc.) that appears to be caused by a Tick bite. This allergy is significantly different than most because traditional food allergies have always been associated with reaction to proteins—but alpha-gal, the trigger in this condition, is a sugar found in mammalian meat. Plus, food allergy reactions are usually immediate (within minutes to an hour), whereas a person with the alpha-gal allergy doesn’t react for four to six hours.

Discovered by researchers investigating unusual reactions to a new cancer medication, they observed that in certain areas of the United States — North Carolina, Arkansas, Missouri, Virginia and Tennessee—patients were showing an unusual hypersensitivity to the drug cetuximab. Researchers determined that the antibodies were to a sugar, galactose-alpha-1,3-galactose—or alpha-gal, for short. (Alpha-gal is present in non-primate mammals but not in humans.) The researchers finally discovered the trigger for this condition when they looked at a map that charted the occurrence of Rocky Mountain spotted fever, a tick-borne infection. The two maps were a perfect match. Upon follow up interviews, many of the patients reported they had been bitten by a tick or chigger prior to the onset of their “allergy.”

Further research uncovered that all three life stages of the aggressive lone star tick—larva, nymph and adult—feed on humans. The nymphs are often called seed ticks, because they are the size of poppy seeds; sometimes they’re mistaken for chiggers.With this condition, patients are told to avoid all meat from mammals. Some patients cannot tolerate any dairy, while others can tolerate milk in their cereal but have allergic reactions to ice cream or to creamy cheeses, like brie. Some can eat very lean cuts of venison without symptoms. And it appears that Fat plays a key role. That’s because alpha-gal is a sugar that attaches to fat molecules, existing as a glycolipid. The way fats are absorbed in the body may explain the four-hour delay in developing a reaction.

To further confuse the issue, this tick-bite triggered allergy may not last a lifetime. Alpha-gal antibody levels can eventually drop in patients who avoid additional tick bites. In time, some people get a negative blood test for the antibody and pass a food challenge, enabling them to eat meat again.


Gelatin Allergy

Gelatin is a protein that is formed when skin or connective tissue is boiled. Although rare, allergic reactions to gelatin have been reported. Many vaccines contain porcine (pig) gelatin as a stabilizer. Allergy to gelatin is a common cause of an allergic reaction to vaccines. Individuals who have experienced symptoms of an allergic reaction after consuming gelatin should discuss this with their health care provider before getting vaccinated. If a severe allergy to gelatin is known, vaccines that contain gelatin as a component should be avoided.


Seed Allergy

Allergic reactions to seeds can be severe. Sesame, sunflower, and poppy seeds have been known to cause anaphylaxis.  The estimated prevalence of seed allergy is not known. In a study published in 2010, however, researchers at New York’s Mount Sinai School of Medicine concluded that 0.1 percent of the general population may have a sesame allergy, based on a national survey that focused primarily on the prevalence of peanut and tree nut allergy. Seeds are often used in bakery and bread products, and extracts of some seeds have been found in hair care products. Some seed oils are highly refined, a process that removes the proteins from the oil. However, as not all seed oils are highly refined, individuals with a seed allergy should be careful when eating foods prepared with seed oils.


Spice Allergy

Allergies to spices, such as coriander, garlic, and mustard, are rare and are usually mild, although severe reactions to spices have been reported. Some spices cross-react with mugwort and birch pollen, so patients who are sensitive to these environmental allergens are at a higher risk for developing an allergy to spice.


An allergic reaction to food can affect the skin, the gastrointestinal tract, the respiratory tract, and, in the most serious cases, the cardiovascular system. Reactions can range from mild to severe, including the potentially life-threatening condition known as anaphylaxis. In the U.S., food allergy symptoms send someone to the emergency room every three minutes. Symptoms typically appear within minutes to several hours after eating the food to which you are allergic.

Mild symptoms may include one or more of the following:

  • Hives (reddish, swollen, itchy areas on the skin)
  • Eczema (a persistent dry, itchy rash)
  • Redness of the skin or around the eyes
  • Itchy mouth or ear canal
  • Nausea or vomiting
  • Diarrhea
  • Stomach pain
  • Nasal congestion or a runny nose
  • Sneezing
  • Slight, dry cough
  • Odd taste in mouth
  • Uterine contractions

Severe symptoms may include one or more of the following:

  • Obstructive swelling of the lips, tongue, and/or throat
  • Trouble swallowing
  • Shortness of breath or wheezing
  • Turning blue
  • Drop in blood pressure (feeling faint, confused, weak, passing out)
  • Loss of consciousness
  • Chest pain
  • A weak or “thread” pulse
  • Sense of “impending doom”

How a Child Might Describe a Reaction

Children have unique ways of describing their experiences and perceptions, and allergic reactions are no exception. Precious time is lost when adults do not immediately recognize that a reaction is occurring or don’t understand what a child is telling them. Some children, especially very young ones, put their hands in their mouths or pull or scratch at their tongues in response to a reaction. Also, children’s voices may change (e.g., become hoarse or squeaky), and they may slur their words. The following are examples of the words a child might use to describe a reaction:

  • “This food is too spicy.”
  • “My tongue is hot [or burning].”
  • “It feels like something’s poking my tongue.”
  • “My tongue [or mouth] is tingling [or burning].”
  • “My tongue [or mouth] itches.”
  • “It [my tongue] feels like there is hair on it.”
  • “My mouth feels funny.”
  • “There’s a frog in my throat.”
  • “There’s something stuck in my throat.”
  • “My tongue feels full [or heavy].”
  • “My lips feel tight.”
  • “It feels like there are bugs in there.” (to describe itchy ears)
  • “It [my throat] feels thick.”
  • “It feels like a bump is on the back of my tongue [throat].”

If you suspect that your child is having an allergic reaction, follow your doctor’s instructions and treat the reaction immediately.

Food Intolerance

Food intolerance is different from true food allergies.  It is delayed in its onset and has less serious (not life threatening) consequences but can be very annoying just the same.  It is IgG mediated which is a delayed immune response.  After consuming a food the symptoms occur more gradually and may not occur for 6-24 hours.

If you have a food intolerance, you may be able to eat small amounts of the offending food without trouble. You may also be able to take steps that help prevent a reaction. For example, if you have lactose intolerance, you may be able to drink lactose-free milk or take lactase enzyme pills that aid digestion (such as Lactaid).

Food intolerance may be caused by a variety of reasons.

  • Poor Digestion from lack of needed digestive enzymes – e.g. lactose intolerance
  • Dysbiosis – lack of healthy flora particularly impacts carbohydrate digestion
  • Altered stomach pH
  • Lack of bile production – created an intolerance to fatty foods
  • True intolerance for items like gluten or casein including a more severe form of gluten intolerance known as Celiac disease
  • Sensitivity to food additives – e.g. sulfites in dried fruits and red wine
  • Stress – not fully understood

Understanding the cause of the food intolerance gives guidance to how you can best manage and treat them.  Identifying them is the first step and we routinely do this at Crossing Back to Health with the help of the Zyto evaluation.  We have successfully treated many people with food intolerances, helping them to figure out the root cause for their symptoms and to eliminate the annoying symptoms associated with them.  Learn more about the symptoms associated with food intolerance…(link to below).



Typical symptoms of food intolerance may include:

  • Nausea
  • Stomach pain
  • Diarrhea (irritable bowel symptoms)
  • Gas , bloating, heartburn
  • Congestion
  • Headaches (including migraines)
  • Irritability and nervousness
  • Fatigue
  • Brain fog and attention issues
  • Hyperactivity
  • Agitation
  • Eczema
  • Asthma
  • Frequent infections – e.g. ear and sinus infections

Do you think you are suffering from a food allergy or food sensitivity issue? Want some relief?

+ Cross Back to Health Today!

  1. Burks W. Clinical manifestations of food allergy: An overview. Accessed March 16, 2011.
  2. Guidelines for the diagnosis and management of food allergy in the United States: Summary of the NIAID sponsored expert panel report. Bethesda, Md.: National Institute of Allergy and Infectious Diseases. Accessed March 16, 2011.

 What’s the difference between a food intolerance and food allergy?  James T C Li, M.D., Ph.D.  Mayo Clinic Website – Expert Answers – Jun. 03, 2011