Some of you may…just may…have a few questions about food intolerance. For example, you may ask:
- Are food intolerances the same thing as food sensitivities?
- Are food allergies the same thing as food intolerances?
- How can I tell if I have food intolerances? Food sensitivities? Food allergies?
- What can I do about food allergies? Anything?
- What can I do about food intolerance?
- What causes any of these?
How about we answer some of these questions?
Food Intolerances, Food Sensitivities, and Food Allergies Defined
Let’s cut to the chase—food intolerance and food sensitivities are terms that are used to describe the same thing, though according to some professionals, sensitivities are due to imbalances in the gut bacteria. Food allergies are quite different and are based on a reactive immune response and involving a specific immunoglobulin—IgE. Food allergies can also be life-threatening and require hospitalization, whereas food intolerances usually just make you miserable.
A food intolerance/sensitivity indicates that the individual has difficulty digesting a certain food. The most common food intolerance is to dairy containing lactose, a type of sugar. Coming in at second place is gluten intolerance. Gluten is a type of protein found in various varieties of wheat, barley, rye, and triticale. After gluten, there are intolerances to caffeine, salicylates (found in a wide variety of foods), amines (produced by bacteria and also found in a variety of foods), fermentable oligo-, di-, mono-saccharides and polyols, or more commonly, FODMAPs, sulfites, fructose (a sugar found mainly in fruit), eggs, Monosodium glutamate, or MSG, various additive and preservatives, and artificial sweeteners. Essentially, one can be intolerant to one or many different foods—and that food can be just about anything!
Symptoms vary—different individuals and different foods may have several different sets of symptoms. But in general, most people with food intolerances will suffer one or more of the following soon after eating a particular food. Symptoms, however, can start up to 48 hours after eating the food and can sometimes last for days! This can make it difficult to determine exactly what food you are intolerant or sensitive to!
Common Symptoms of Food Intolerance
- Diarrhea
- Abdominal bloating or discomfort
- Skin rashes or skin flushing
- Fatigue
- Runny nose
- Headaches
- Acid reflux
- Intestinal gas
Food intolerance can be caused by the lack of a digestive enzyme. In lactose intolerance, for example, the enzyme lactase is missing. Another possible cause of food intolerance is a digestive condition, such as irritable bowel syndrome (IBS) or celiac disease—an autoimmune disease where the body mistakes gluten for a normal body component. The use of additives and preservatives is another possible cause, though, for most food intolerances, the cause is unknown.
There is a test for lactose intolerance, but for most food intolerances, there is no diagnostic test universally accepted. Sometimes adding digestive enzymes can help. Keeping a food diary, tracking symptoms, and an elimination diet can help determine the food(s) you are intolerant to, but these take time—and lots of dedication!
Food allergies(1), on the other hand, occur when the immune system is centrally involved. It occurs almost immediately after eating the food—even the smallest amount of food can trigger an allergic response. Remember, in food intolerance, the effects may not occur until 48 hours have passed. The severity of the allergic reaction ranges from mild to severe to life-threatening. Anaphylaxis, a very severe allergic reaction, can occur in some people.
The symptoms of food allergy are somewhat different as well, and most are typical allergic responses.
Common Symptoms of Food Allergies
- Tingling around the mouth
- Itching around the mouth
- Hives
- Swelling of the mouth, lips, tongue, and throat
- Wheezing
- Trouble breathing
- Dizziness
- Abdominal pain
- Nausea and vomiting
- Diarrhea
The most common foods that people are allergic to include:
- Gluten
- Celery
- Crustaceans such as crabs, lobster, shrimp, and prawns
- Eggs
- Fish
- Milk
- Mussels and oysters
- Peanuts
- Sesame
- Soybeans
- Tree nuts (almonds, hazelnuts, walnuts, Brazil nuts, cashews, pecans, pistachios, macadamia nuts)
- Foods preserved with sulfites (some dried fruit)
Testing is available to diagnose a food allergy—either a skin-prick test or a blood test. In the skin-prick test, a tiny amount of the chemical components of food are placed just under the skin with a very small needle. Within about 20 minutes, there will be a reaction if you are allergic to that food. The reaction is considered positive if a “wheal and flare” appears. The “wheal and flare” reaction is a reddened skin swelling.
Blood tests can also detect the presence of a type of antibody specific to allergies known as IgE. These tend to be less specific and take longer for results to be produced.
Managing Food Intolerances and Allergies
The main approach to both food intolerances and food allergies is to avoid the food. This may mean some research and time dedicated to reading labels—but “The Food Allergy Labeling and Consumer Protection Act of 2004 (FALCPA)(2) mandates that manufacturers of packaged foods produced in the United States identify, in simple, clear language, the presence of any of the eight most common food allergens – milk, egg, wheat, soy, peanut, tree nut, fish and crustacean shellfish – in their products. The presence of the allergen must be stated even if it is only an incidental ingredient, as in an additive or flavoring.” By the way, this law only applies to some foods and not to meat, poultry, and eggs. It also does not apply to alcoholic, cosmetic, or personal hygiene products. People with true allergies may react to products applied to the skin!
If you don’t know which food(s) you are intolerant of—you can try the elimination diet. People with true allergies usually know precisely what they are reacting to because the response is usually immediate, but people with food intolerance often have a more difficult road to discovery—the elimination diet can help.
Guidelines to a Successful Elimination Diet
Before you start any new diet plan, it is recommended that you consult a trusted healthcare professional!
An elimination diet is just what it sounds like—you start eliminating specific foods you suspect you may be intolerant of for a period of at least 4 weeks, keep track of any symptoms (or lack of symptoms) and then slowly re-introduce the food, one at a time, starting with small amounts, keeping track of any symptoms, and then (assuming you are feeling fine), slowly increasing the amount of that food.
It’s a lot of work, time, and energy, to be sure—but it is the best and most reliable way we know how to determine what food(s) you are intolerant to.
There are lots of variations for an elimination diet. Arguably, the simplest way is to remove the most common foods that cause intolerance for 1 month. This usually means eliminating ALL gluten, dairy, caffeine, dried fruit (sulfites), artificial sweeteners, soy products, fast food, fried foods, and alcohol for the month. That is not an easy thing for most people to do!
An alternative is to eliminate the 6 most common foods that cause intolerance. These are gluten, dairy, eggs, soy, fish, and nuts. You may already have some idea of foods that affect you—if your particular food intolerance is not one of those, feel free to eliminate that one. If, on the other hand, you are certain that eggs are not a problem, there is no need to eliminate them—but, just in case, keep that specific food in mind for future elimination.
Plan ahead because removing these foods means you are going to have to use suitable alternatives. That may mean finding new recipes and trying them out, and reading all labels carefully. Start keeping a food journal because you will want to compare what you are experiencing before you start the elimination!
It is important to eliminate the foods you choose to eliminate completely for at least 4 weeks because it takes time for your body to heal from the effects of that food. Better if you could do it for 6-8 weeks, but at least 4 weeks.
Keeping your food journal allows you to keep track of any symptoms you feel- or don’t feel! It can help keep you motivated. Keep track of your mood, as well, as food intolerances can show up as depression, anxiety, irritability—or getting hyper!
After 4 weeks, start re-introducing only one food at a time. Slowly add back the food—use only small amounts of that food in one sitting and allow at least 2 days to pass, keeping track of any symptoms you experience. If all is well, you can slowly increase the amount of food, always waiting 2 days between increases and monitoring how you are feeling. Once you are confident that you have no problems with that food, start re-introducing the next eliminated food, following the same process. If at any point a food gives you a problem, stop eating it!
You can see that this will take some time before you know what you are intolerant of—knowing this before can help you “stick with the program”.
If any food gave you symptoms when re-introducing it, eliminate that food from your diet for 2-3 months and then try to slowly re-introduce it.
Takeaways
Food intolerances and food sensitivities are different and more difficult to diagnose than food allergies. The elimination diet is essential in the treatment of any of these conditions, particularly because food allergies can be so severe.