FOOD ALLERGIES, SENSITIVITIES, AND INTOLERANCES

Surely everyone has come across the concepts of allergy, sensitivity, and intolerance related to food.

The packaging of food products must indicate their allergenic ingredients to provide information for those who have strong reactions to certain ingredients.

Many people experience digestive problems after consuming certain foods. This signals our sensitivity. In such cases, our immune system is tested by the food components that are frequently or excessively consumed.

There are those who experience similar gastrointestinal discomfort when consuming certain ingredients and components. This is due to their bodies not producing adequate digestive enzymes to break down the problematic foods, rendering them unusable for their bodies. In such cases, the inhabitants of the gut flora can adapt to the indigestible components and produce metabolites that cause various symptoms during their breakdown.

The problem is complex, so it is worth exploring what causes the discomfort related to food. With this knowledge, we can develop an appropriate diet to ensure our health and well-being.

 

FOOD ALLERGIES, SENSITIVITIES, AND INTOLERANCES

So there are true food allergies, as well as sensitivities and intolerances. Let's briefly review the essential differences among the causes:

Food allergy - immunological hypersensitivity (IgE reaction)

Food sensitivity - delayed immune reaction to foods (IgG and IgA reactions)

Food intolerance - insufficient or incomplete digestive disorder due to the individual indigestibility of certain foods

 

IMMUNOGLOBULINS

Immunoglobulins (also known as antibodies) are proteins produced by our immune system in response to antigens such as lectins, fungi, bacteria, viruses, and toxins.

The antibodies are produced by our body as an immune system response to substances with which we have come into contact and that the body recognizes as foreign substances (which is why they are called antigens). The antibodies produced by the immune system can also react to other foreign substances, including pollens, dust, hair, and food. The role of antibodies is to assist the body in its fight against environmental, foreign, risky, and dangerous "intruders."

The body produces different immunoglobulins against different antigens. There are five classes of immunoglobulins, and we need to focus on three of them in relation to symptoms related to food because they are nutrition-related.

Immunoglobulin E (IgE) - antibodies against allergic reactions, typically causing an immediate reaction in the body to the introduced foreign substance. Immunoglobulin G (IgG) - characteristics of food sensitivities, typically manifesting with a delayed onset, with a milder direct impact but can last longer than traditional IgE allergies. Immunoglobulin A (IgA) - plays a role in the functioning of the mucosal immune system.

IgG Food Sensitivities

IgG (immunoglobulin G) refers to delayed immune reactions, which are also called food sensitivities and often referred to as delayed allergies.

In the case of IgG reactions, the immune system produces IgG antibodies that can lead to inflammatory processes. Symptoms of IgG reactions can occur up to three days after consuming the problematic food.

Many individuals suffering from IgG food sensitivities may go for years, or even their entire lives, without being able to identify the specific component they are sensitive to or being aware that their health issues are related to dietary sensitivities.

It is often challenging to pinpoint the exact food causing the problem due to the delayed onset of symptoms. Therefore, tests or an elimination diet can be helpful.

(Several clinical studies suggest that eliminating IgG-positive foods often improves symptoms of irritable bowel syndrome, autism, ADHD, cystic fibrosis, rheumatoid arthritis, and epilepsy.)

Symptoms of IgG Allergies

The symptoms of IgG reactions are generally more subtle and can last much longer than those of traditional IgE allergies.

IgG antibodies lead to inflammatory processes and do not involve the release of histamines, so immediate hypersensitivity reactions such as itching, hives, and swelling do not occur.

Symptoms of IgG reactions can occur up to 72 hours after consuming the food. These symptoms may include:

• Anxiety
• Headaches
• Nausea
• Depression
• Bloating/gas
• Diarrhea
• Constipation
• Acid reflux
• Joint pain
• Fatigue
• Mood swings
• Hyperactivity
• Shortness of breath
• Weakness
• Brain fog/memory problems

Certain conditions may arise from food sensitivities, such as:

• Arthritis
• Migraine
• Ear infection
• Eczema
• Sinusitis
• Asthma
• Colitis
• Irritable bowel syndrome (IBS)

IgG and Leaky Gut

IgG sensitivities often coexist with various digestive issues, including leaky gut syndrome (also known as increased intestinal permeability).

If you struggle with leaky gut, it means there are microscopic holes in the lining of the small intestine, allowing food particles, toxins, and bacterial byproducts, and in severe cases, bacteria themselves, to enter the bloodstream, which then burdens the immune system.

Leaky gut can induce inflammation and changes in the gut flora, reducing the ratio of beneficial bacteria and leading to dysbiosis. Several studies have shown that alterations in the community and composition of gut bacteria can play a role in the development of certain chronic diseases. Chronic, prolonged inflammation and toxicity can cause autoimmune diseases and other related disorders.

IgG Testing and Elimination Diet

Due to the delayed onset of IgG symptoms, it is often challenging to pinpoint exactly which foods are causing the problem. That is why IgG testing is the best way to determine food sensitivities. IgG tests can be performed by several laboratories, and it is advisable to consult with your healthcare provider or research online to find out which one to use.

Once you have identified the foods to which your body reacts, you should follow a strict avoidance-elimination diet for a certain period of time (typically around 3 months). During this time, do not consume the foods flagged by the test.

A nutrition expert can guide you through the process of conducting an elimination diet and provide personalized regenerative therapy (lifestyle and dietary changes) to strengthen your immune system. After the three-month period of strict diet, it is recommended to undergo repeat testing to confirm whether the sensitivity has subsided or if any new ingredients should be avoided. Those for which the sensitivity has resolved can be cautiously and gradually reintroduced into your diet.

 

FOOD INTOLERANCES

While food allergies trigger a rapid response from the immune system, sensitivities elicit a slower immune response, and food intolerances do not involve the immune system at all. However, food intolerances can cause similar symptoms to food allergies/sensitivities, which often leads to confusion among people. In most cases, food intolerance is caused by a lack of specific enzymes needed for the digestion/processing of certain foods. For example, individuals with lactose intolerance do not have sufficient lactase enzyme, which is necessary for the breakdown of lactose found in milk. However, lactose that enters the digestive tract can be well digested by the majority of intestinal bacteria. The proliferation of lactose-consuming microbes disrupts the balance of gut flora, and their metabolic byproducts strain the body's detoxification system and lead to digestive complaints (such as bloating, diarrhea, cramps). These can ultimately contribute to the development of chronic diseases and chronic inflammation that burdens the entire body.

The condition can be differentiated as either congenital complete lactase deficiency, which can be safely diagnosed through genetic testing, or acquired (e.g., inflammatory bowel disease, infection, gluten intolerance, antibiotic use) transient intolerance, or milk protein allergy.

Individuals with histamine intolerance may lack the DAO or HNMT enzymes responsible for histamine degradation, leading to an excess of histamine. The excess histamine can trigger local and indirect sensitivity reactions.

Many foods and beverages contain histamine.

Generally, histamine is broken down by the enzymes DAO and, to a lesser extent, histamine-N-methyltransferase (HNMT). However, several factors can disrupt the functioning of DAO and HNMT.

If the body fails to break down histamine from ingested foods, histamine can leak through the intestinal mucosa and enter the bloodstream, triggering an immune response.

Several prescription drugs can affect the levels of DAO and HNMT in the body. Some examples of these medications are:

Antibiotics Antidepressants Gastrointestinal drugs Antiarrhythmics used for treating cardiac arrhythmias Antihypertensives used for treating high blood pressure Muscle relaxants Narcotics Local anesthetics

Meanwhile, over-the-counter and prescription nonsteroidal anti-inflammatory drugs (NSAIDs) can influence the body's histamine metabolism. Some examples of these drugs, known as NSAIDs, include:

Ibuprofen (Advil, Motrin) Aspirin Indomethacin (Indocin) Diclofenac (Voltaren)

Additionally, high alcohol consumption and health conditions that damage the intestinal mucosa can lead to histamine intolerance.

If you have certain food intolerances, you may be able to prevent the problem by supplementing with specific deficient enzymes. This might allow you to consume small amounts of the problematic food.

Histamine intolerance is slightly different from other food intolerances because histamine accumulates. It is best to avoid these foods until the histamine levels decrease.

 

FOOD INTOLERANCE TESTING

There is no specific blood test for food intolerance since it does not involve the immune system, and immunoglobulins will not be present in the blood.

In the case of histamine intolerance testing, the level of the DAO enzyme in the blood is measured. If it is below the threshold value, it can be assumed that there is a decrease or possibly a deficiency in enzyme production. For an accurate diagnosis, a genetic test can be performed to determine if there is a predisposition to impaired histamine processing. (At the time of writing this article, I did not find such routine testing available in our country.)

Three main genes play a central role in histamine processing:

 

HNMT DAO MAO

If any of these genes are inactive, the breakdown of histamine may slow down, and symptoms of histamine intolerance may occur.

Genetic testing (testing for SNPs) is not part of the protocol in our country. If you decide to undergo such testing abroad, it is important to have the raw data files interpreted and reviewed by a healthcare professional or a qualified nutrition specialist, as a high number of genetic polymorphisms can lead to misinterpretations by individuals without expertise in the field.

It should be noted that having a genetic variation does not necessarily mean that the gene is turned on and causing problems. We all have genetic differences (single nucleotide polymorphisms - SNPs), so it is best to consult with a professional who is knowledgeable about SNPs before becoming overly concerned about the findings of the testing.

References

https://doi.org/10.1016/j.foodres.2020.109780

https://www.ncbi.nlm.nih.gov/books/NBK27117/ 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1774223/ 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3314037/ 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2695393/ 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5346110/ 

https://www.ncbi.nlm.nih.gov/pubmed/3791631 

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