When growing up, I don’t remember any of my friends or their family members being allergic, intolerant or sensitive to foods.
Now days restaurants offer gluten, dairy, soy and nut free options. Lactose free cheese and milk and gluten free bread is available in supermarkets. Children are no longer allowed peanut butter sandwiches or nuts at school because this type of allergy is on the rise.
One of the main reasons for the increased frequency of food allergies seems to be excessive regular consumption of a limited number of foods often hidden in commercially prepared foods. Other culprits are high levels of preservatives, stabilisers, artificial colourings and flavourings now added to food.
My advice: read food labels!
I’m really passionate about this subject, since I battled with food-based reactions for years. One of the reasons that I became a nutritionist with a special interest in gut health.
There can be some confusion around what allergies, intolerances and sensitivities are and these terms are often used interchangeably. Let’s explore the differences.
Allergies are easy to understand because there is usually a pretty quick reaction to the offending food. Symptoms include rashes, welts, swelling of the lips, eyes, face, tongue and/or throat, runny nose, sneezing and so on. Reactions can be subtle, or they can be life threatening.
Food allergies are immune mediated reactions, where there is an overreaction to a normal and harmless food protein. The body will create an antibody called immunoglobulin E (IgE) when it is first exposed to the offending food.
When that food is eaten again, these IgE antibodies will signal cells of the immune system to attack the foreign invaders. These ‘immune’ cells, will release a chemical called histamine causing inflammation and the symptoms associated with food allergies.
Food allergies are usually identified early in life but can develop in later years. The best way of identifying allergies is through the skin prick test and IgE test.
What is food intolerance?
A food intolerance is an adverse physiologic response to food(s). It is due to a ‘mechanical’ problem such as the inability to break down and digest a food because of an enzyme deficiency. Unlike true food allergies, it doesn’t elicit an immune response.
Lactose intolerance occurs when the body doesn’t produce the enzyme lactase to break down lactose. Some people have difficulty breaking down certain sugars and these are then poorly absorbed in the small intestine. These dietary sugars are called Fermentable Oligo-saccharides, Di-saccharides, Mono-saccharides and Polyols (FODMAPS). They are thought to play a role in irritable bowel syndrome.
Those suffering from food intolerances are prone to gut related symptoms such as cramping, constipation, loose stools and/or wind. Symptoms can take longer to appear, anywhere from 30 minutes to 48 hours or more after eating. They are not life threatening, just really uncomfortable and embarrassing for some.
When we cannot break down our food optimally, the gut environment can change and cause an imbalance between good and bad bacteria and yeasts. These food particles can also cause damage to the gut wall, leading to inflammation.
The golden standard for food intolerance testing is doing a temporary elimination diet followed by a controlled food challenge to identify dietary triggers. Breath tests can be helpful in identifying fermentable carbohydrate intolerance, such as lactose and fructose.
What is food sensitivity?
They are food-based immune reactions that can take up to three days to appear. Food sensitivities are IgA and IgG mediated and are produced in response to allergens in the blood, gut and other mucous membranes.
One of the theories is that delayed food sensitivities develop due to intestinal permeability AKA ‘leaky gut’. When this happens, large protein molecules get through into the blood stream and this can set the stage for IgG mediated immune responses to food.
Around 80% of our immune system lives behind the gut wall and its purpose is to protect us from infection. Our immune system scans the environment for proteins found on the surface of bacteria, yeast and other nasties. It will tag these proteins for destruction. If food proteins are getting through that shouldn’t, our immune system will readily tag and attack these protein structures that it comes into contact with.
Symptoms of food sensitivities are broader than just digestive symptoms and can include headaches, joint pain, skin issues, chronic fatigue and many others.
There are a number of tests available, many of which are controversial and not recognised medically. The tricky part of identifying a food sensitivity is that it can be delayed for up to 72 hours or more.
The aim is to eliminate foods that may be causing problems for you. Common foods include gluten, corn, rice, nightshades, legumes, eggs, dairy, nuts, sugar, alcohol and soy.
Food sensitivities can be supported with dietary modifications. If you avoid the foods you are sensitive too and take measures to heal your gut and improve digestion, you are likely to be able to re-introduce these foods down the track without any adverse reactions.
What can you do?
If you are suffering from uncomfortable digestive symptoms or experience fatigue, joint pain, eczema, unexplained weight gain, irritable bowel syndrome, Crohn’s, mood disorders and other conditions, some foods may be impacting your health.
Seek advice from a qualified practitioner who can help you identify food triggers, support your immune system and heal your gut. Over time you may be able to reintroduce some of the foods that you enjoyed in the past. The key is to be patient, since this type of healing can take time.