BePure Clinical Manager and BePure Holistic Health Consultant, Lisa Grey
dives deeper into food allergies, intolerances, and sensitivities and how you can identify them to support the well being of your whole being.

Food-based reactions are something Lisa battled with along her own health journey, and is something she is very passionate about helping her clients with. Based on her clinical and personal experience, Lisa believes it is really important to identify food reactions and the type of food-based reaction an individual may be experiencing.

This is because the root reason for each type of food reaction is very different from a biochemistry standpoint but can present itself in a number of similar symptoms. Each food reaction requires a different approach or solution to helping a client achieve dietary freedom. Understanding the situation at hand can alleviate the frustrations and confusion that frequently accompany food-based reactions, particularly when the person has "exhausted all" options to determine the cause of their reaction.

What Are Food Intolerances, Allergies or Sensitivities?

Food reactions are often termed food allergies, food intolerances, and/or food sensitivities. These terms are thrown around interchangeably, but they all mean very different things when we take a look at biochemistry.

When we find ourselves reacting negatively to nutritious foods we could previously eat without a reaction, it’s important to distinguish and identify what type of biochemical reaction(s) may be driving our symptoms.

Identifying the underlying mechanism(s) at play makes it easier to support the body with a targeted, biochemically individualised approach to achieving dietary freedom. This individualised approach helps to remove the frustration and wonderment that often accompany different types of food reactions. To better understand these three terms, let’s break each of them down into their biochemical processes.

Food allergies

Food allergies are immune reactions where the body produces Immunoglobulin E (IgE) antibodies against a food protein, leading to the release of histamine from two types of immune cells called mast cells and basophils. This histamine release leads to an increase in inflammation and immune activity in the body, which is where we see signs of allergy.

These signs include: hives, rashes, abdominal pain, sneezing, coughing, wheezing, bloating, runny nose, red or itchy eyes, skin flushing, shortness of breath, and swelling of the lips, nose, eyes, ears, face, tongue, nasal passages, and/or throat.

Reactions can range from subtle reactions, like mild seasonal allergies, to dramatic reactions, such as those seen with anaphylaxis.

These reactions can range from subtle reactions like mild seasonal allergies, to dramatic reactions, such as those seen with anaphylaxis. Anaphylaxis is a life-threatening reaction characterized by hives, severe swelling, trouble breathing, and shock. Allergic reactions are purely driven by the immune system and occur very quickly after ingesting the triggering food - usually within a 24-48 hour time period. True food allergies are often identified at birth but can develop later in life. Allergies are unlikely to be either caused or reversed by adopting a different diet for a period of time. However, in some cases, avoiding these foods and adopting an AIP (auto-immune paleo) or paleo dietary approach may help reduce the severity of symptoms if an individual accidentally or intentionally comes in contact with a known dietary allergen(s).

Once we reach adulthood we have passed the stage of life (infancy and early childhood) in which IgE-mediated food allergies tend to first begin, but still have the capacity to develop food allergies. A recent survey of over 50,000 adults discovered roughly half (47%) the study participants to have an allergic reaction to shellfish or nuts that had developed in adulthood. Other research papers have shown that when allergies do develop later in life, they usually begin when people are in their early 30’s and are more likely to develop in individuals with a history of hay fever, asthma, and/or eczema.

Scientists are still trying to figure out what causes this later development of allergic reactions to foods we previously handled well, but have suggested the combination of environmental exposures, viral infections, and/or hormonal changes whilst in a state of weakened immunity may play a key role in allergy development. Scientists have also suggested that some form of cross-reactivity may also be responsible for this phenomenon.

In this theory, an individual may start reacting to certain fruits, grains, and/or vegetables that contain proteins similar to those of an existing allergy, such as penicillin, mould, plant pollen or dust mites. For example, this is why people with a latex allergy might have to also avoid bananas.

When it comes to diet, allergies do not develop in adulthood from avoiding a food for too long. Put more simply, we cannot induce an egg allergy by going a year without eating eggs or induce a shellfish allergy by not eating prawns frequently enough! This simply isn’t how IgE-mediated allergies work in adulthood.

Food Intolerances

Food intolerances are reactions to foods that are not triggered by an immune reaction. These reactions are generally driven by the body’s lack of digestive capacity or inability to break down the food we ingest.

In some cases, these types of reactions are driven by enzyme deficiencies that prevent us from properly breaking down components in our food. ie. lactose intolerance. In other cases, poor production of bile, stomach acid and pancreatic enzymes by the organs in the upper part of the gastrointestinal system can be the driving factor behind these reactions.

Unlike allergies, food intolerances tend to have side effects that are primarily gastrointestinal or gut related (i.e. cramping, constipation, bloating, diarrhea, upset stomach, and/or gas), and unlike allergic reactions, are not life-threatening. Symptoms can also take a longer time to appear, anywhere from several hours to several days.

Many of the food based reaction derived from an inability to process or metabolize a substance may lead to inflammation, changes in the gut microbiome, damage to the gut wall, impose excess strain on the liver, and/or damage to other tissues. Other mechanisms that result in adverse food reactions that are non-immune mediated occur via the effects an imbalance in the type and number of microbes within the gastrointestinal tract i.e. gut dysbiosis, small intestinal bacterial overgrowth (SIBO), small intestinal fungal overgrowth (SIFO).

When we cannot break down our food in the way it was intended to be, the environment within the gastrointestinal tract changes as does the balance of good and bad bacteria and yeasts within this environment. This is why it’s incredibly important to support the body with microbial balance and upper gastrointestinal digestive function as these types of food reactions can often lead to the development of immune-mediated food sensitivities.

Some of these types of reactions can be easily mitigated by supporting the upper digestive tract with supplementation or using specific dietary strategies to help aid digestion whilst others require more in-depth support to rebalance the microbial balance within the gastrointestinal tract.

Food sensitivities, likewise, can often be supported when we approach them from the angle of gut health, and/or temporarily avoiding the offending food components, like FODMAPS.

Food sensitivities

Food sensitivities have a less consistent definition in the medical field but are generally referred to as food-based immune reactions driven by immunoglobulins (IgG, IgA and sometimes IgM) that are not IgE or classic allergic responses. Immune-mediated food reactions of this type can take between 48 and 72 hours to appear and often develop from gastrointestinal permeability, or “leaky gut”.

Leaky gut occurs when the wall of the gastrointestinal tract becomes damaged and “leaky” preventing it from controlling ‘traffic’ in and out of the body. When this single cell layered structure becomes “leaky”, protein structures from virtually any food (yes, you can find protein structures in all foods, including grains, vegetables, nuts, and seeds) we ingest is permitted to venture into the body, where they interact with the immune system sitting behind the gut barrier.

Over 80% of our immune system lives beneath the gut wall.

Over 80% of our immune system lives beneath the gut wall to protect us from infection (food poisoning would be so much worse if we didn’t have this system) and is designed to tag and attack foreign invaders.

One way it does this is by looking for specific proteins found on the surface of bacteria, yeast and/or parasites and tagging these proteins for destruction so that our immune system (i.e. IgG and IgA) can attack and destroy these foreign invaders. These protein structures are found in all living things and are all made of the same 20 amino acids or protein building blocks. With this understanding, it is easy to see how the immune system is able to readily tag and attack (almost) all protein structures it comes in contact with, including the ones in our food. When these protein structures are well digested into smaller ‘building blocks’ prior to leaving the gastrointestinal tract, the immune system does not tag them as foreign as it is designed to see these smaller molecules as ‘normal’.

It is only when larger protein structures that are not designed to be seen by the immune system escape the gastrointestinal tract, that immune-mediated food reactions may occur. When the immune system is exposed to these foreign proteins and attacks them, a whole host of unpleasant symptoms may arise.

Non-IgE-mediated sensitivities (IgG, IgA, and IgM reactions), tend to be much easier to support with dietary modifications. If we avoid the foods we are intolerant to and take measures to restore our gut barrier function and digestive capacity, we can often re-introduce these foods 6 months later, without adverse reactions.

With careful avoidance and an appropriate gut rebuilding strategy, IgG and IgA antibodies against food disappear within six to twenty-four months. This varying length in time depends on how reactive we were to these foods initially - prior to doing any work on our gastrointestinal and immune health. Once these IgA’s and IgG’s have disappeared, we are generally able to reintroduce these foods into our regular dietary regime without problems.

Key takeaway

Why is it important to distinguish between all these reactions?
Because the root reason for these reactions and the solution to helping you achieve dietary freedom are very, very different! This is why at the BePure Clinic we test for food sensitivities using a gold standard ELISA test that identifies IgG, IgA and IgE reactions to over 90 foods.

About Lisa Grey

Lisa is a qualified Holistic Nutritionist and Personal Trainer and has a Bachelor of Psychology from Massey University. A dancer, fitness professional, foodie and utter nerd, Lisa loves to make the science of health fun and has been helping people with their wellbeing for 10 years.

Lisa is passionate about educating and empowering people with the tools they need to take charge of their own health journey mentally, emotionally and physically. She loves translating scientific evidence into analogies, client-friendly lingo and practical tasks that clients can utilise on a daily basis.

With a personal health journey driving her passions, Lisa has a particular interest in hormonal health, fertility, gut health, mental wellbeing, exercise appropriation and how all of these knit together to make the whole being well.