Decoding Your Plate: A Deep Dive into Food Intolerance and the IgG Antibody Test

IgG Food Intolerance Test: In today’s health-conscious world, terms like “food allergy,” “food intolerance,” and “food sensitivity” are thrown around frequently, often interchangeably, leading to widespread confusion. While they all signify an abnormal reaction to certain foods, the mechanisms behind them and their manifestations can vary significantly. This comprehensive guide aims to demystify these reactions, particularly focusing on food intolerance as detected by the IgG antibody test.

Understanding the Landscape of Food Reactions: Allergies vs. Intolerances

The first step in navigating adverse food reactions is to understand the terminology. Essentially, any abnormal reaction to food that manifests in various ways can be termed a “food allergy,” “food intolerance,” or “food sensitivity/hypersensitivity.” These reactions can either involve the activation of the immune system and antibody production (immune-mediated) or be non-immune-mediated.

Immune-Mediated Reactions: The Body’s Defense System on Alert

Reactions that trigger an immune response are commonly referred to as “allergies.” These occur when the body over-reacts to foods that typically don’t cause issues in most people. This over-reaction prompts the immune system to produce antibodies that attack “foreign” food proteins, which it perceives as a threat. Allergies are broadly categorized into four types (I, II, III, and IV), based on the activated part of the immune system and the time it takes for a reaction to occur.

For adverse food reactions, two types of allergies are most commonly associated:

• Type I Allergy (IgE-mediated allergy/true allergy): These are characterized by the rapid production of IgE antibodies and the release of histamine upon exposure to an allergen (e.g., peanuts, shellfish). Symptoms, often immediate, can appear within seconds or minutes after ingesting certain foods and may include rashes, sneezing, difficulty breathing, and even anaphylactic shock. Identifying the culprit food in a Type I allergy is usually straightforward, and these foods typically need to be avoided for life.
• Type III Allergy (IgG-mediated allergy/food intolerance/food hypersensitivity): These reactions involve the production of IgG antibodies and the gradual formation of antigen/antibody complexes. These complexes can get deposited in tissues, leading to chronic inflammation. Symptoms are “delayed-onset,” appearing several hours or even days after food ingestion. Common symptoms associated with Type III allergies include anxiety, depression, IBS (Irritable Bowel Syndrome), headaches/migraines, fatigue, hypertension, eczema, asthma, joint pain, chronic rhinitis, arthritis, weight problems, and fibromyalgia. A key distinction here is that it’s often possible to eliminate the offending food(s) for a short period and then gradually re-introduce them once symptoms have improved.

Non Immune-Mediated Reactions: Beyond the Immune System

Reactions that do not involve an immune response are often categorized as “food intolerances.” These can stem from sensitivities to specific chemicals or additives found in food, or more commonly, from enzyme deficiencies.

• Enzyme Insufficiency/Deficiency:
  • Lactose Intolerance: This is caused by a deficiency of lactase, an enzyme necessary to break down lactose (a complex sugar found in dairy products like milk, cheese, and yoghurts). Symptoms typically include bloating, diarrhea, and flatulence.
  • Histamine Intolerance: This results from elevated histamine levels due to a deficiency or inhibition of diamine oxidase (DAO), an enzyme that breaks down histamine. It’s aggravated by foods high in histamine (e.g., red wine, cheese, tuna fish) and also by foods that can trigger histamine release (e.g., citrus fruits, bananas, tomatoes, chocolate). Symptoms can range from migraines, dizziness, bowel/stomach problems, rhinitis, depression, irritation, and reddening of the skin.

The IgG Antibody Test: Focusing on Type III Intolerances

The IgG antibody test specifically measures immune-mediated, Type III allergy (IgG-mediated) reactions. While Type III reactions are technically classified as “allergies,” the colloquial term “food intolerance” is often used for this type of reaction, and this terminology is adopted throughout the Guidebook.

Interpreting Your Test Results

Your Test Report will list the foods your blood sample was tested for, with the number of foods depending on the specific test chosen. You’ll receive two types of reports:

• Food Groups: Foods are listed alphabetically within their respective food categories.
• Order of Reactivity: Foods are listed according to the strength of your antibody reaction.

Each food will have a numerical value in a colored box next to it, representing the concentration of IgG antibodies detected in Units per milliliter (U/ml). A higher value indicates a stronger immune response to that particular food. Foods are categorized as:

• ELEVATED: Indicates a high antibody reaction. These are considered primary “problem foods” and should be eliminated from your diet for at least three months.
• BORDERLINE: Indicates a moderate antibody reaction. These are moderate “problem foods” that should be reduced and rotated for at least three months to prevent an increase in intolerance.
• NORMAL: Indicates no significant reaction. These foods can generally be eaten without restriction, unless you’ve previously experienced an adverse reaction to them.

If your test identifies ELEVATED or BORDERLINE IgG antibody levels and you’re experiencing adverse symptoms, this suggests an intolerance to those specific foods. Removing them from your diet often leads to symptom improvement.

Important Considerations for Your Dietary Journey

Embarking on a new dietary regimen based on your results requires careful planning and understanding:

• No Elevated Foods, Still Symptoms? If your test shows no ELEVATED foods but you still experience symptoms of food intolerance, it’s recommended to avoid BORDERLINE foods for three months.
• Managing Multiple Elevated Foods: If you have many ELEVATED foods, trying to eliminate all of them at once can be challenging. It might be easier to completely avoid the top 4 or 5 foods with the highest antibody concentrations, and then reduce and/or rotate the remaining foods with moderate antibody concentrations.
• Initial Worsening of Symptoms: It’s normal to feel worse for a few days after eliminating specific foods. Your body needs time to overcome withdrawal symptoms, so perseverance is key. Improvements may take a few weeks to become apparent.
• Food Rotation: To rotate foods, aim to eat them no more than once every 4-5 days. For example, if rotating wheat, you might eat wheat bread on day 1, oat cakes on day 2, corn cakes on day 3, rye crispbread on day 4, and durum wheat pasta on day 5.
• Nutrient Replacement: If you eliminate ELEVATED foods, especially those that are significant sources of nutrients (like milk for calcium), it’s crucial to obtain those nutrients from alternative food sources.
• Avoiding New Intolerances: Don’t replace an eliminated “problem” food exclusively with another single food from the same group. For example, if you eliminate wheat toast, don’t eat porridge oats every day. Vary your food choices within the “NORMAL” category to prevent developing new intolerances. Eating a wide variety of foods also ensures a broader range of vitamins and minerals.
• Incomplete Elimination: While complete elimination often yields the greatest improvement, don’t worry if you can’t always avoid “problem” foods or need to occasionally deviate from your diet. Just restart as soon as you can.
• Impact of Prior Avoidance on Test Results: If you haven’t consumed a particular food within the last three months, your test might show a NORMAL reaction due to low IgG antibody levels. To accurately test for intolerance, the food should be included in your daily diet (or every other day) for 4-6 weeks before testing, unless it causes extreme symptoms.
• No Improvement After 2-3 Months? If your symptoms haven’t improved after 2-3 months despite eliminating ELEVATED foods, it’s possible that IgG-mediated food intolerance isn’t the cause of your symptoms. In such cases, seeking medical advice from a doctor or healthcare professional is recommended.
• Gliadin and Gluten: Gliadin is a protein fraction of gluten, found in wheat, barley, and rye. The test analyzes gliadin separately. If your test shows an ELEVATED response to gliadin, you should avoid foods containing wheat, barley, or rye, even if these grains are listed as NORMAL on your report.

Planning Your Diet: A Strategic Approach

Changing your dietary regime requires a strategic approach:

• Consult a Professional: If you have a medical condition, are pregnant, or on medication, always discuss proposed dietary changes with a doctor or health professional.
• Focus on What You Can Eat: Instead of dwelling on the foods you need to avoid, concentrate on the wide variety of delicious foods in your “NORMAL” range that you can consume freely.
• Read Labels Diligently: Many ready-made meals and sauces contain hidden ingredients. Always check food labels carefully before purchasing.
• Vary Your Foods: Eating a diverse range of foods, including different colored fruits and vegetables, and various protein sources, ensures you get a wide array of vitamins and minerals and decreases the risk of developing new intolerances.
• Plan Ahead: Take a day or two to prepare for your new diet. Plan daily menus in advance, incorporating as many NORMAL foods as possible. Collecting recipe ideas and shopping ahead will make the transition smoother.
• Eliminating/Rotating Specific Foods: ELEVATED or BORDERLINE foods should be eliminated or rotated for at least three months. While many foods are easy to substitute with NORMAL foods from the same group, common culprits like wheat, gluten, dairy, eggs, soya, and yeast are more challenging due to their prevalence in everyday foods. The Guidebook provides specific advice for avoiding these challenging ingredients.

Strategies for Avoiding Common Problem Foods:

• Dairy: If you have an ELEVATED reaction to milk, eliminate all milk and milk products. Ensure you obtain protein, calcium, and vitamins A, D, and B complex from alternative sources like soya, cod liver oil, sardines, nuts, red meat, green leafy vegetables, rhubarb, figs, mushrooms, oranges, apricots, prunes, pumpkin seeds, sesame seeds, lentils, and legumes. Be mindful of hidden dairy ingredients such as casein, whey, and milk solids. Explore dairy-free alternatives like oat milk, rice milk, soya milk, and nut milks.
• Eggs: If egg white and/or yolk show an ELEVATED reaction, eliminate them and egg proteins. Substitute with foods that offer similar nutritional value, as eggs are a good source of protein, calcium, iron, zinc, and B-vitamins. Look for egg-free pasta, noodles, clear soups, and use egg replacers in baking.
• Wheat: An ELEVATED reaction to wheat means avoiding all wheat and wheat products for at least three months. Wheat is a source of fiber, B vitamins, chromium, and zinc, so replace these nutrients from alternatives. Be aware of hidden wheat in ingredients like binder, bran, semolina, starch, and modified starch. Explore wheat-free breads (rice, rye, potato, corn flour), pasta (rice, quinoa, corn, buckwheat), biscuits (maize, oats), and breakfast cereals (cornflakes, porridge oats, millet puffs).
• Gluten: If gliadin (a gluten protein) shows an ELEVATED reaction, eliminate gluten-containing grains (wheat, barley, rye) even if the individual grains aren’t elevated. Some people with gluten intolerance can tolerate oats, but be cautious of wheat contamination. Alternative gluten-free flours include amaranth, potato, quinoa, buckwheat, rice, corn, ground nuts, sago, lentil, chickpea/gram, soy, millet, and tapioca.
• Yeast: An ELEVATED reaction to Baker’s or Brewer’s yeast means avoiding yeast-containing products for at least three months. This includes moulds, mouldy cheeses, and other fungi. Yeast is surprisingly prevalent in processed foods, making careful planning essential. Avoid breads, pizzas, pastries, yeast extracts, fermented foods (beer, wine, soy sauce), vinegar-containing foods (pickles, ketchup), mushrooms, dried fruits, and over-ripe fruits. Yeast-free options include pasta, brown rice, corn tortillas, home-made breads with baking powder/soda, fresh vegetables, legumes, lean proteins, fish, shellfish, free-range eggs, soya milk, cottage cheese, and plain organic live yoghurt.

Monitoring Your Progress and Re-introducing Foods

• Food/Symptom Diary: Keep a diary to record foods consumed and any changes in symptoms (better or worse). This helps identify patterns and track your progress.
• Gradual Re-introduction: After at least three months, and only when symptoms have subsided, ELEVATED foods can be gradually re-introduced. Introduce one food at a time and monitor your symptoms over a five-day period. If symptoms return, avoid that food for another month or two. If no symptoms appear, the food can be included occasionally.
• Tips for Re-introduction: Be patient. Don’t over-indulge in your favorite foods to prevent intolerances from re-occurring. Re-introduce foods with the lowest antibody levels first, referring to your “Test Report: Order of Reactivity.” Wait five days between introducing each new food.

Frequently Asked Questions

• Foods Not Detected by the Test: Some foods can cause IgE-mediated allergic reactions (Type I allergy), which the test does not detect. Non-immune-mediated reactions to chemicals (e.g., amines in chocolate, cheese, red wine causing migraines), food additives (e.g., tartrazine triggering hives, rashes, asthma), MSG (causing sweating, dizziness), or “Nightshade” alkaloids (affecting joints) are also not detected. Enzyme deficiencies, like in lactose intolerance, are also not identified by this test. Always avoid foods if you suspect they cause adverse effects.
• What does U/ml mean? U/ml stands for “Units per milliliter” and measures the concentration of food-specific IgG antibodies in your blood sample.
• Do I need a nutritionist? It’s advisable to consult a registered nutritionist after receiving your results. They can provide personalized dietary advice, supplement recommendations, and ongoing support.
• Cow’s milk ELEVATED vs. Lactose Intolerance: An ELEVATED reaction to cow’s milk in the test indicates an IgG-mediated intolerance to milk proteins, not lactose intolerance. Lactose intolerance is due to a lactase enzyme deficiency, which the test doesn’t detect.
• Suitability for Children: The test is suitable for children aged 2 years and older.
• Gluten-free vs. Wheat-free: These terms are not interchangeable. A product can be wheat-free but contain gluten (from barley or rye), and vice versa. The test separates gliadin testing from wheat, barley, and rye extracts. If gliadin is ELEVATED, eliminate all gluten-based grains. If wheat, rye, or barley are ELEVATED but gliadin is not, the reaction is likely to other proteins in those grains.
• Why is gliadin tested separately? Gliadin is only soluble in alcohol and cannot be extracted with water-soluble food extracts used for the test, hence its separate testing.
• Caution when removing food groups: Always be careful when changing your diet.
• Do I need a re-test? Most people do not need a re-test, especially if symptoms have improved and foods have been successfully re-introduced. If you desire a re-test, wait at least six months.
• Reacting to never-eaten foods: This can occur due to “cross-reaction,” where some foods contain identical food proteins (antigens) even if they are unrelated, leading to an ELEVATED result.
• No improvement? If after three months of dietary changes, symptoms persist, food intolerance might not be the primary cause, and further investigation by a healthcare professional is advised.

The IgG antibody test provides a valuable guide for dietary changes. By understanding your individual reactions and thoughtfully planning your diet, you can work towards improving your symptoms and achieving better overall health. Remember, these test results are a guide and should complement advice from your healthcare professional.