All About Food Allergy and Food Intolerance

Imagine a person having a not so pleasant physical reaction after eating a certain food at a party. We would assume that person must be suffering from an allergic reaction to food. And it could be a correct assumption.

Or not.

Perhaps that person has some form of food intolerance instead. Food allergy, food intolerance, same difference right? As far as many people are concerned, if you have a problem eating something or if you have a bad physical reaction to a certain food, that’s food allergy right there.

Apparently not. So let us examine how these two terminologies are defined.

  •  Food Allergy

It is an abnormal reaction to a certain food by the body’s immune system. The food in question is seen by the immune system as an allergen. Common foods that trigger an allergic reaction in adults include shellfish, fish, peanuts and walnuts or other tree nuts. In children, the food triggers include milk, peanuts, tree nuts, eggs, wheat and soy.1Allergic reaction to food can range from mild to severe. A severe allergic reaction is called anaphylaxis

  • Food Intolerance

It is a non-allergic or non-IgE food hypersensitivity. IgE stands for immunoglobulin-E or antibodies produced by the immune system. Simply put, food intolerance means difficulty in digesting certain foods.2 Just like with food allergies, there are certain foods that often get associated with food intolerance. These include grains containing gluten, dairy products and “gassy foods” like cabbage, beans, broccoli, asparagus, onions, cauliflower, pears etc.

 What’s the difference between food allergy and intolerance?3

Now that we have the textbook definition of these two phrases, perhaps it will help us understand them better if we point out their differences.


Food Intolerance

Food Allergy

It can be uncomfortable.

It can be life threatening.

It involves the digestive system and is most likely due to an enzyme deficiency.

It involves an abnormal or harmful reaction by the body’s immune system.

May not be triggered if only a small amount of the offending food is eaten.

Can be triggered by exposure to even microscopic amounts of the offending food, either by ingestion, touching or inhalation.

Its symptoms are often (but not always) limited to digestive problems.

Food allergy symptoms are generally evident on the skin (itchiness, hives, swelling). Gastrointestinal symptoms can include diarrhea and vomiting. Respiratory symptoms often accompany skin and gastrointestinal symptoms – they don’t normally appear alone.

Its symptoms appear within a few hours up to 2 days after intake of the offending food. 2

Its symptoms appear soon (within a few minutes to 2 hours) after exposure to or intake of the food allergen.4


General Signs and Symptoms


Food Intolerance5

Food Allergy6

Breathing problems (rapid breathing) with asthma-like symptoms.

Mouth: The most frequent food allergy symptoms are itching and/or swelling of the mouth.

Burning sensation on the skin.

  • Eyes & nose: The eyes and nose mimic hay-fever symptoms - swelling and becoming red and itchy. The nose will be runny (or congested) and itchy as well, with sneezing thrown-in.


  • Lungs: Asthma-like symptoms appear including wheezing, coughing and breathlessness.

Nervousness, tremors and palpitations

  • Gastrointestinal tract: Symptoms include bloating, nausea and vomiting, pain and diarrhea.

Sweating, tightness across the face and chest

  • Skin: Hives appear, with itchy white or pale red swellings. This usually disappears within hours.


  • Anaphylaxis is an acute and potentially life-threatening reaction to food allergens where a person’s skin itches, the person feels unwell and becomes dizzy and nauseous. The person actually feels the beating of their heart and may pass out with a drop in blood pressure. On top of all these, the person may get nettle rash (hives), hay fever and an asthma attack.

Causes of Food Allergy and Intolerance

We have established that food allergy and food intolerance are in fact two different animals, so now we can begin looking at what causes them.

  • Causes of Food Intolerance2
    • Missing/Insufficient Enzymes - Certain enzymes are needed in order to digest foods properly and completely.

For example, carbohydrate intolerances mean that a person is unable to digest and absorb fructose, sorbitol or other simple sugars. The most well-known of these conditions is lactose intolerance. A lactose intolerant person lacks or does not have enough of the enzyme lactase. Lactase is responsible for breaking down the sugars in milk (lactose) into smaller molecules that can be broken down further so that they can be absorbed by the body through the intestine. If lactose does not get broken down, it remains in the digestive tract where it eventually causes bloating, spasm, stomach ache, gas and diarrhea. Lactose intolerant people are often misdiagnosed as allergic because its symptoms are similar to those caused by allergy to milk protein.

Another example is diamine oxidase (DAO) deficiency. DAO is an enzyme responsible for the metabolism, oxidation and deactivation of histamine that enter the body thru foods. If DAO activity is low, the person can suffer from food histaminosis or histamine intolerance. Unlike food allergy, the symptoms do not come out as a result of eating any specific food, they may be triggered by any food even if it has low histamine level.7

    • Food additives – More and more of the foods that we eat today contain additives to make them look more appealing, to enhance their flavors, and to make them last longer. Examples include antioxidants, food coloring, artificial flavorings, flavor enhancers, emulsifiers, sweeteners, preservatives etc. There are thousands of additives that the food industry uses and some of them have been known to cause adverse reactions.
      •  MSG (monosodium glutamate) – a flavor enhancer that has been known to cause headaches especially when used excessively.
      • Nitrates/Nitrites – used on processed meats to enhance their coloring and to prolong their shelf life. They have been known to cause itching and skin rashes. They can form nitrosamines in the body which can increase the risk of developing cancer.
      • Sulfites – used as preservatives or food enhancer commonly added to wines and some medications.
      • Artificial sweeteners like aspartame.
    • Transport defects8 – There are molecules inside the body that are called transporters. Some of these transporters may have some defects. Examples of transporter molecules include GLUT 2 whose job is to transport glucose, fructose or galactose and GLUT 5 to transport fructose. When these carbohydrates don’t get transported into the intestinal cells, they end up intact the large intestine where they ferment and produce gases like methane, carbon dioxide, hydrogen and short-chain fatty acids. These gases cause abdominal pain, flatulence, bloating and diarrhea.
    • Bacterial overgrowth in the small bowel – People who have undergone bowel resection or have long undergone proton pump inhibitor treatments with omeprazole or ranitidine are especially at risk of bacterial overgrowth. They are more susceptible to food intolerances after eating a number of foods because the bacterial overgrowth release excessive bacterial decomposition products in the gut.
    • Infections – Intolerance symptoms may also be caused by giardiasis, a chronic infection of the digestive organs or infections caused by ETEC (enterotoxigenic) and EHEC (enterohemorrhagic) E. coli strains. Ever notice how when people are suffering from any kind of diarrhea, they are told to stay away from eating greasy foods? It’s because the infection causing their diarrhea makes them unable to tolerate oily foods.
    •  Structural abnormalities of the digestive tract – One example is a case of intestinal diverticula where food is trapped within the saclike structures resulting to bacterial overgrowth. Other examples of structural abnormalities include: 
      • Chronic inflammatory bowel disease
      • Chronic pancreatitis
      • Colonic diverticula
      • Esophageal achalasia
      • Gallbladder disease leading to fat malabsorption
      • Lympho-vascular abnormalities
      • Post-inflammatory strictures or other abnormality
  • Causes of Food Allergy

When the body’s immune system mistakenly identifies a particular food or something in it as potentially harmful, it responds by making cells release antibodies called immunoglobulin-E (IgE) to fight off or neutralize the allergen. The next time this food enters the system, no matter how small the amount, the antibodies sense it and immediately triggers the immune system to release histamine and other chemicals into the bloodstream to try and combat the invaders. The internal battle that ensues produces the food allergy symptoms that alert the person something is going on inside the body.

The majority of food allergies can be traced to certain proteins found in these 8 primary allergenic foods:

  • Egg
  • Fish
  • Milk
  • Peanut
  • Shellfish
  • Soy
  • Tree nuts
  • Wheat


Types of Food Intolerances


Food Trigger(s)


Alternative Foods

Gluten intolerance

(non-celiac gluten sensitivity NCGS)

Gluten is an ingredient that gives dough its elasticity and makes it rise. It is also used as thickening agent in sauces, processed foods and meat products. It is found in barley, rye, wheat, triticale and any foods made with these grains. Examples of foods to avoid:

  • Bulgur
  • Couscous
    • Common Symptoms:
    • belly pain
    • bloating
    • diarrhea
    • feeling unwell
    • nausea
    • tiredness
  • Cracked and durum wheat
  • Emmer
  • Farina
  • Faro
  • Gliadin
  • Kamut
  • Matzo
  • Semolina
  • Spelt


Less common symptoms:

  • anxiety
  • confusion
  • headache
  • joint or muscle pain
  • numbness
  • stomach pain


  • Buckwheat
  • Corn
  • Millet
  • Rice
  • Agar-agar
  • Guar gum
  • Carob flour
  • Potato flour

Alcohol intolerance

Alcohol intolerance is caused by a genetic condition making a person unable to efficiently break down alcohol. Oftentimes however, the condition is a reaction to the ingredients found in the drink like:

  • Chemicals
  • Preservatives (sulfites)
  • Grains(wheat or barley)
  • Histamine (byproduct of brewing or fermentation)
  • Brewer’s yeast
  • Flavors (hops)
  • fruits

The only way to avoid these reactions is to stay away from any alcoholic drink.

  • Flushed face
  • warm, red, itchy skin rashes
  • Makes pre-existing  asthma worse
  • Stuffy or runny nose
  • Low blood pressure
  • Nausea and vomiting
  • Diarrhea


  • Virgin mixed drinks
  • Soda water
  • Seltzer
  • Tonic water
  • Citrus soda

Lactose_ Intolerance

  • Butter
  • Cheese
  • Cream soups/sauces
  • Ice cream
  • Milk, Evaporated milk, condensed milk
  • Yogurt
  • Puddings, custards
  • Whipping cream
  • Dairy coffee creamer

Primary symptoms:9


Other symptoms:

  • abdominal bloating
  • abdominal distention
  • nausea
  • Lactose-free milk
  • Soy milk
  • Almond milk
  • Rice milk
  • Coconut milk 10



Types of Food Allergies


Food Allergen


Alternative Foods

Celiac Disease

  • Wheat
  • Wheat germ
  • Rye
  • Barley
  • Bulgur
  • Couscous
  • Farina
  • Graham flour
  • Kamut Matzo
  • Semolina
  • Spelt
  • Triticale

Other foods that often contain gluten:

  • beer
  • breaded foods
  • canned baked beans
  • cereals
  • cold cuts
  • commercial bullion and broths
  • chocolate milk
  • egg substitutes
  • energy bars
  • flavored teas and coffees
  • blue cheeses
  • Flour-dusted, frozen French fries
  • fruit fillings and puddings
  • gravy
  • hot dogs
  • ice cream
  • imitation crab meat, bacon
  • instant hot drinks
  • ketchup
  • malt vinegar
  • malt/malt flavoring
  • marinades
  • mayonnaise
  • meatballs
  • meatloaf
  • communion wafers
  • non-dairy creamer
  • oat bran
  • oats
  • processed cheeses
  • roasted nuts
  • root beer
  • salad dressings
  • sausage
  • seitan
  • soups
  • soy sauce
  • teriyaki sauces
  • syrups
  • tabbouleh
  • trail mix
  • veggie burgers
  • vodka
  • wheatgrass
  • wine coolers



Flours and other foods made with:

  • Beans
  • Amaranth
  • Arrowroot
  • Buckwheat
  • Corn
  • Flax
  • Cornmeal
  • Millet
  • Oat bran
  • Potatoes
  • Quinoa
  • Rice
  • Sorghum
  • Soybeans
  • Tapioca
  • Teff

Egg allergy

Eggs – both egg yolks and egg whites contain allergy-causing proteins but allergy to egg whites is more common. Some foods that contain egg include:

  • Bread and cakes
  • Desserts
  • Ice cream
  • Mayonnaise
  • Meat products
  • Pancakes and Yorkshire puddings
  • Quiches
  • Sauces and spreads
  • Hives
  • Allergic rhinitis -  sneezing, runny nose,nasal congestion
  • stomach cramps
  • Nausea and vomiting
  • Asthma symptoms -wheezing, coughing, shortness of breath or chest tightness
  • Anaphylaxis


In some baking recipes, the following can be used as food substitutes for 1 egg:

  • Apple sauce
  • Banana
  • Mixture of water, vinegar and baking powder
  • Mixture of yeast and water
  • Mixture of water, oil and baking powder
  • Water and gelatin
  • Water and ground flaxseed

Peanut Allergy

Peanuts or any of the following ingredients:

  • Arachis oil (another name for peanut oil)
  • Artificial nuts
  • Beer nuts
  • Peanut oil
  • Goobers
  • Ground nuts
  • Lupin- a flour substitute in gluten-free food.
  • Mandelonas
  • Mixed nuts
  • Monkey nuts
  • Nut meat
  • Nut pieces
  • Peanut butter
  • Peanut flour
  • Peanut protein hydrolysate
  • Hives
  • Itching or tingling in the mouth or throat
  • Nausea
  • Runny or congested nose
  • Anaphylaxis
  • Hummus
  • Sunflower seeds
  • Sunflower seed butter
  • Soy nuts
  • Soy nut butter
  • Coconut butter
  • Chickpeas


Shellfish Allergy

  • Clams
  • Crabs
  • Crayfish
  • Cuttlefish
  • Lobster
  • Mussels
  • Octopus
  • Oysters
  • Prawns
  • Scallops
  • Shrimp
  • Snail
  • Squid
  • Abdominal pain
  • Nausea/vomiting
  • Diarrhea 
  • Tingling in the mouth
  • Congestion, trouble breathing, wheezing
  • Hives or eczema
  • Lightheadedness
  • Dizziness
  • Fainting
  • Swelling of the face, ears, tongue, lips, throat, fingers or hands
  • Anaphylaxis

For the same nutritional benefits, the following foods may be used as substitute for shellfish:

  • Beans
  • Lentils
  • Organic Chicken
  • Grass-fed beef
  • Free-range eggs

Importance of Testing

Some people might argue that the only sure-fire way of determining if a person has any type of food intolerance or food allergy is to expose them to all known food triggers or allergens.

But are you willing to risk it, especially considering that some food allergies can be life threatening? Also, most food intolerances don’t show symptoms up to 2 days after exposure to certain foods, making it difficult to pinpoint the culprit from among the foods eaten in the past 2 days. Parents would not want to expose their children to certain food allergens or subject them to the discomforts brought on by certain food intolerances. If there is anything that can be done at all to avoid all of these, won’t you be willing to do it?

Food allergy testing or food intolerance testing will do just that, help us take control of what happens to our body by knowing which foods to stay away from. Studies show that over $25 billion is spent annually by families who have children with allergies and other food sensitivity conditions. Imagine the kind of savings that will be realized if these families get the information they need in order to better manage their children’s allergies; not to mention all the time they would otherwise spend on enjoyable activities instead of always waiting around for treatment at clinics or emergency rooms.

A particularly comprehensive test panel available from LiveWellTesting is called the Platinum Food Intolerance Test Kit 320. It will test a person’s cellular response to all of these 320 substances:

  • 200 foods
  • 50 medicinal herbs and functional foods
  • 20 food colorings/additives
  • 20 types of molds
  • 20 antibiotics/anti-inflammatory agents
  • 10 environmental chemicals

A collection kit will be shipped to you and a mobile collector will set up a collection date at your convenience. Results are available within 5-7 days after sample is received at the lab. Results are presented in color-coded chart that clearly indicates which foods are to be avoided and which are safe.

A Premium Food Intolerance Test Kit250 is also available for all of the above except the 50 medicinal herbs and 20 antibiotics.

A Regular Food Intolerance Test Kit200 will test for the following:

  • 150 foods
  • 20 Food Colorings/Additives
  • 20 types of molds
  • 10 environmental chemicals

For a more specific test, Gluten Sensitivity & Celiac Disease Testing Kit

will establish Celiac Disease or simply gluten insensitivity. This test goes a long way in helping Celiac Disease sufferers, 83% of whom are undiagnosed or misdiagnosed with other conditions. Results for this test are available 3-5 days after sample is received at the lab.


For any type of food intolerance or food allergy, the best form of treatment is avoidance of the problem foods. Whether eating at home or eating out, people who have these conditions should be constantly vigilant of their food intake. Find out what ingredients went into the manufacture or the preparation of the food. Inform party hosts or restaurants of your particular dietary requirements so accidents can be avoided.

  • Food intolerance

Any type of food intolerance is primarily managed with an exclusion diet. The idea is for the affected person to avoid problem foods for a certain period of time, between 2–6 weeks. During this period he/she is encouraged to keep a journal and note down improvements (if any). Afterwards, the problem food(s) is/are reintroduced at increasing amounts carefully watching out for reactions.

Reactions vary between individuals, and treatment is tailored accordingly.11

The FALCPA (Food Allergy Labeling and Consumer Protection Act of 2004) has mandated that all packaged foods must contain information in simple and clear language about the top 8 food allergens, namely egg, milk, peanut, tree nuts, fish, shellfish, soy and wheat. People with known allergies are to carry at least 2 doses of epinephrine or adrenaline for emergency treatment. Mild reactions may be treated with oral antihistamines.

Facts, Statistics & Trends12

  • An estimated 1% of adults and 7% of children have food allergies. This means that many of the children who have them outgrow their allergies as they age.
  • An estimated 10% of Americans are lactose intolerant.
  • There are 8 foods that are generally considered to be allergenic and responsible for 90% of allergic reaction to food. They are egg, dairy, peanuts, tree nuts, fish, shellfish, wheat and soy. From these 8 food groups, more than 170 foods have been reported to cause allergic reactions.
  • According to the NIH, as many as 30 million people in the U.S. have food intolerance, some 4-5 times more than those with food allergies.
  • Allergy to sesame is on the rise and is considered an emerging concern.
  • An estimated 15 million Americans have food allergies, 5.9 million of which are children under 18.
  • Approximately 30% of children who have food allergies are allergic to more than one food.
  • From 1997 to 2011, the CDCP reports that food allergy in children increased by 50%.
  • The prevalence of peanut or tree nut allergy in American children have more than tripled between 1998 and 2008.
  • An ER visit is caused by an allergic reaction to food every 3 minutes.
  • The only effective treatment for anaphylaxis is epinephrine (aka adrenaline) and it should be injected within minutes upon the onset of food allergy symptoms.
  • Families with children with food allergies spend nearly $25 billion annually for their care.
  • Children with food allergy are 2x more prone to bullying.
  • 20-25% of epinephrine administrations in schools are for people whose allergy wasn’t known to them at the time.
  • Most fatal anaphylaxis cases are triggered by food consumed by the victims outside of their home.
  • While some food allergies may be outgrown, allergies to peanuts, tree nuts, fish and shellfish are generally for life.
  • By 2020, the market for food allergy and intolerance products is expected to exceed $24.8 billion globally.














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