Chronic Symptoms, Food Sensitivities & Gut Health:
50 Questions Answered
Megan Pennington, BSc, CLT — Integrative Health Practitioner & Certified LEAP Therapist — answers the questions your doctor hasn't had time to address.
If you're living with a chronic condition — IBS, autoimmune disease, fibromyalgia, persistent skin issues, chronic fatigue, migraines, or unexplained symptoms — there are questions you've typed into Google or asked an AI assistant late at night. Questions your doctor didn't have time to answer, or didn't know how to answer.
This page is for you. We've compiled the 50 questions we hear most often in clinical practice — and answered each one based on over 20 years of experience working with chronic illness using MRT food sensitivity testing and the LEAP Protocol.
"Standard labs show what's broken. They don't show what's driving the fire. That's the gap functional testing fills — and where most chronic illness stories finally start to change."
These aren't generic answers. They're the explanations our practitioners give clients in practice — grounded in the science of immune reactivity, gut function, and chronic inflammation, and shaped by two decades of clinical practice.
Finding the Root Cause
What Conventional Medicine Misses
These are the questions people ask when they've tried conventional care and are ready for a different approach — someone who investigates causes, not just symptoms.
Root-cause investigation combines complete health history, MRT food sensitivity testing, and targeted functional labs to build a full picture of what's driving your specific pattern of symptoms.
We begin every client relationship with a thorough intake: symptom timeline, health history, previous treatments, diet, stress load, medications, and family history. This gives context no test alone can provide. MRT testing then identifies food-specific immune triggers — the most frequently missed factor in conventional care.
From there, depending on the clinical picture, we may investigate gut integrity, microbiome balance, nutrient status, and hormone function. Most chronic conditions are multifactorial — but food-driven inflammation is part of the puzzle for nearly every client we work with. Starting there almost always creates the foundation for everything else to work better.
Most importantly: root-cause work means asking why until you reach a factor that can actually be changed — not stopping at a diagnosis name that just describes the symptom.
Learn more about our root-cause approach to chronic illness →
Normal results mean the tests ordered didn't find what they were designed to find — not that nothing is wrong. The next step is functional testing that asks different questions.
Standard labs are designed to detect pathology — diagnosable conditions with measurable abnormalities. They are not designed to detect food-driven immune activation, early gut barrier dysfunction, or the inflammatory dysregulation underlying most chronic fatigue, brain fog, pain, and digestive symptoms.
Functional testing fills this gap: MRT food sensitivity testing reveals immune triggers standard labs don't assess. Gut permeability markers identify barrier dysfunction. Comprehensive stool analysis maps microbiome imbalances. These tests ask the questions routine bloodwork doesn't — and they routinely reveal the answers that have been missing.
If you've been told everything is normal but you still feel unwell, that's not a verdict. It's information about which questions haven't been asked yet.
📖 Blog: Why Your Labs Are Normal But You Still Feel SickDiscover what MRT testing reveals that standard labs can't →
Conventional medicine asks: what medication can suppress this symptom? Functional medicine asks: what is causing this symptom in the first place?
The difference is investigative depth. Conventional medicine excels at acute care, disease diagnosis, and pharmacological symptom management. What it typically doesn't do is investigate why the symptom developed — the underlying food triggers, gut dysfunction, microbiome imbalances, and immune dysregulation that drive most chronic conditions.
Functional medicine uses advanced testing to identify those individual factors and addresses them directly. This is why people who have been managed — but not improved — on conventional treatment often experience dramatic improvement when root-cause factors are finally identified and removed. The two approaches are not in conflict; they're complementary, and we work alongside conventional providers routinely.
How our functional medicine approach addresses root causes →
Healing chronic inflammation requires four simultaneous actions: identify and remove triggers, repair damaged tissues, restore healthy microbiome and immune regulation, and address the nervous system physiology keeping the inflammatory cycle running.
No single intervention achieves lasting results because chronic inflammation is multifactorial. The LEAP Protocol addresses the first two phases — identifying reactive foods through MRT testing and rapidly reducing inflammatory load through personalized dietary changes. Gut restoration work (mucosal repair, microbiome rebalancing) addresses the structural damage. Targeted nutritional support corrects deficiencies that impair healing.
The fourth element — nervous system regulation — is one most approaches miss entirely. Chronic stress keeps the HPA axis dysregulated and the immune system primed for reactivity. Mind-body practices that restore vagal tone and downregulate the threat response are a meaningful part of lasting recovery, not an optional add-on.
This layered approach is why it produces lasting results where single-intervention approaches fail. Healing isn't one thing — it's a coordinated process.
See how we treat chronic conditions with a root-cause framework →
Testing & Hidden Triggers
Why Standard Tests Miss the Real Cause
MRT is the most validated test for food-driven inflammation. Beyond that, intestinal permeability markers, comprehensive stool analysis, and micronutrient panels complete the picture standard labs leave blank.
Standard inflammatory markers like CRP and ESR confirm that inflammation is present — but tell you nothing about what's causing it. For identifying specific food triggers, MRT (Mediator Release Test) is the most clinically supported option available, measuring 176 foods and chemicals with 94.5% reported sensitivity.
Gut barrier testing identifies intestinal permeability. Comprehensive stool analysis maps microbiome composition, pathogen presence, and digestive enzyme function. Organic acid testing can reveal mitochondrial dysfunction contributing to chronic fatigue. Micronutrient panels frequently uncover deficiencies in selenium, zinc, iron, B12, and vitamin D — all commonly depleted in chronic illness.
Together these tests build the picture that routine bloodwork doesn't — showing not just that something is wrong, but what specifically is driving it.
MRT measures your immune system's inflammatory response to 176 foods and chemicals — capturing the delayed reactions that standard allergy tests miss entirely, with 94.5% reported sensitivity.
The test works by exposing a blood sample to each of the 176 antigens and measuring changes in the ratio of liquid to solid components — a validated proxy for immune cell activation and mediator release. Unlike IgG-only food sensitivity panels (which measure a single antibody type), MRT captures multiple immune pathways simultaneously, identifying a broader and more clinically accurate range of reactive foods.
Results are categorized into three groups: non-reactive (green), moderately reactive (yellow), and reactive (red). This creates a personalized reactivity map used to build the LEAP Protocol — starting your diet from the safest foods and systematically expanding as inflammation decreases.
Allergy tests only detect IgE reactions — the immediate responses causing hives or anaphylaxis. Food sensitivities use completely different immune pathways that standard allergy tests are simply not designed to detect.
IgE-mediated reactions (true allergies) involve pre-formed antibodies triggering immediate mast cell degranulation. Food sensitivities involve non-IgE mechanisms — IgG and IgA antibody complexes, cellular immune activation, complement cascades — that produce symptoms 2 to 72 hours after eating the trigger food.
A completely negative allergy panel in someone with significant food-driven chronic illness is entirely expected — and unfortunately, is often interpreted as "food is not your problem" when the reality is that the wrong test was used. MRT measures the pathways that allergy tests don't, which is why it regularly identifies triggers in people who've tested negative everywhere else.
The most accurate approach is MRT blood testing — measuring immune mediator release to 176 foods and capturing the delayed mechanisms that symptom diaries and elimination diets can't reliably identify.
Symptom diaries fail for food sensitivities because the delay between eating and reacting (2–72 hours) makes the connection invisible. Elimination diets are slow, restrictive, and often remove the wrong foods based on population averages. MRT bypasses both limitations by measuring the immune response directly in the lab. Results are used to build the LEAP Protocol — a phased reintroduction plan that systematically restores dietary variety as inflammation resolves.
Why generic elimination diets fail — and what works instead →
MRT is a clinically validated blood test with published research and 94.5% reported sensitivity — measuring actual immune cell responses, distinct from the more controversial IgG-only panels.
The confusion around food sensitivity testing stems from lumping together very different tests. IgG-only panels have been legitimately criticized as over-broad and poorly predictive. MRT is different: it measures the net outcome of multiple immune pathways simultaneously (immune cell volume changes as a proxy for mediator release) — a more clinically meaningful measurement.
Published studies have examined MRT-guided LEAP Protocols for IBS, migraines, and other inflammatory conditions, with consistently positive outcomes. We present MRT as a clinical tool — not a cure-all — and we're always transparent about what it can and cannot tell us. It is the most scientifically supported food sensitivity testing approach currently available, and we've seen results transform health outcomes for clients consistently over 20 years.
Review the clinical research and validation behind MRT testing →
Standard blood tests detect diagnosed disease — not the food-driven immune activation, gut barrier dysfunction, or early inflammatory dysregulation driving most chronic symptoms.
A CBC, CMP, and standard thyroid panel are designed to identify pathology with measurable abnormalities. They are not designed to detect the mechanisms underlying most chronic fatigue, brain fog, digestive distress, joint pain, and skin conditions.
In our clinical experience, clients come to us after years of normal results because the real trigger — a specific food sensitivity continuously activating their immune system — was never tested for. Normal results don't mean nothing is wrong. They mean the right questions haven't been asked yet.
📖 Blog: Why Your Labs Are Normal But You Still Feel SickHow functional medicine investigates what standard labs miss →
Food Sensitivities Explained
Why Healthy Foods Can Make You Sick
Food allergies are immediate IgE reactions. Food sensitivities involve delayed non-IgE immune mechanisms — producing symptoms 2 to 72 hours later — which is why standard allergy tests miss them entirely.
Food allergies involve IgE antibodies triggering mast cell degranulation within minutes — producing hives, swelling, or anaphylaxis. Standard allergy tests and skin prick tests detect these. Food sensitivities involve non-IgE pathways — IgG antibodies, IgA reactions, complement activation, and direct cellular responses — producing chronic, lower-grade symptoms appearing hours to days after eating the trigger. Because of the delay, the food-symptom connection is nearly invisible without testing.
Most people with chronic conditions who've "tested negative for allergies" have significant food sensitivities. They simply haven't been tested for the right thing.
Food allergies vs. food sensitivities — and how MRT tests the difference →
Nutritional value and immune reactivity are independent. The more frequently you eat a food, the higher the probability of sensitization developing — which is why everyday "superfoods" are among the most common MRT-reactive foods.
When the gut barrier is compromised, food proteins cross into systemic circulation where the immune system can mount a reactive response. The nutritional value of the food is irrelevant to whether your immune system has developed a sensitivity to it. Frequent exposure increases the likelihood of sensitization — which is exactly why eggs, avocado, spinach, and almonds appear so often in MRT results.
In our practice, discovering that a client's daily clean-eating staple is their primary inflammatory trigger is one of the most common findings. The frustration and relief clients feel at this discovery — having eaten "perfectly" and still been unwell — is something we encounter regularly.
Why healthy foods make some people sick — the full explanation →
Food sensitivities involve delayed immune mechanisms — reactions take 2 to 72 hours to produce symptoms — making them nearly impossible to identify through observation alone.
IgE-mediated reactions are rapid because pre-formed antibodies trigger immediate mast cell release. Food sensitivity pathways are slower: IgG antibody complexes, cellular immune activation, and complement cascades take hours to generate their full inflammatory mediator response. By the time you feel the symptom, you've eaten 10–15 other things since the trigger food.
This delay is the fundamental reason food sensitivities evade detection without testing. MRT removes this obstacle by measuring the reaction directly in the lab rather than waiting for symptoms to occur.
How MRT captures delayed food reactions that symptom diaries can't →
You eat a reactive food daily, it triggers delayed inflammation you don't connect to the food, and the cycle continues indefinitely — until the trigger is identified through testing.
The mechanism is insidious precisely because it's invisible: you eat eggs every morning, feel fatigued and inflamed most afternoons, and never make the connection because the timing doesn't match. The immune system stays in a constant state of low-grade activation. The gut stays inflamed. Healing never gets a chance to begin.
Many of our clients have been eating their primary inflammatory trigger daily for years — sometimes decades. The moment of testing is often one of the most significant turning points in their health journey: finally understanding why every treatment approach has produced only partial results.
Why your daily "healthy" foods may be fuelling chronic symptoms →
Persistent inflammation is almost always sustained by an ongoing trigger the body hasn't been able to clear — most commonly food sensitivities, gut barrier dysfunction, chronic stress, or hidden environmental exposures.
Inflammation is the body's appropriate response to injury or threat. Chronic inflammation means the threat hasn't been removed. The most common drivers we identify in practice: food sensitivities creating constant low-grade immune activation; gut barrier dysfunction allowing bacterial endotoxins and food proteins into systemic circulation; and chronic stress keeping cortisol dysregulated so the immune system can't properly resolve inflammatory responses.
Removing the trigger — especially food triggers — is the single most impactful first step. Everything else — gut healing, microbiome restoration, stress support — works significantly better once the primary inflammatory fuel source is removed.
How we identify and remove the drivers of chronic inflammation →
Yes — and this connection is one of the most underrecognized in chronic illness. Inflammatory mediators released during food reactions affect not just the gut, but the brain, nervous system, and skin directly.
When the immune system responds to a reactive food, it releases prostaglandins, leukotrienes, cytokines, and other mediators. These compounds affect the gut-brain axis, blood-brain barrier permeability, and neurotransmitter metabolism — producing fatigue, cognitive difficulty, mood instability, and anxiety hours after eating the trigger food. The same systemic inflammatory load manifests in skin as eczema, rosacea, hives, or acne flares.
In our practice, when we remove reactive foods, neurological and skin symptoms consistently improve alongside the physical digestive and pain symptoms. This is not coincidental — it reflects the shared inflammatory biology linking gut, immune, nervous system, and skin function.
📖 Blog: Can Food Sensitivities Cause Fatigue and Brain Fog?How food-driven inflammation affects every system in the body →
Symptom cycling reflects fluctuating inflammatory load — driven by food exposures, stress, hormonal shifts, and sleep quality — not random variation.
When overall inflammatory load exceeds a threshold, symptoms emerge. When it drops below, they ease. This creates the "good weeks and bad weeks" many chronic illness patients describe. Stress raises the threshold by dysregulating cortisol and the immune response. Hormonal fluctuations — especially estrogen, which influences mast cell activity and histamine processing — add another layer of variability. Sleep deprivation independently elevates inflammatory markers.
Identifying and removing the baseline food-driven inflammatory drivers lowers the overall threshold consistently, which reduces both the frequency and severity of cycles.
Why treating the root cause stabilizes symptom patterns long-term →
Gut Health & Leaky Gut
The Gut–Immune Connection
Intestinal permeability ("leaky gut") is a breakdown of the gut barrier, allowing inflammatory compounds into systemic circulation. Repair requires removing triggers, targeted nutritional support, and microbiome restoration — in that order.
The gut lining is a single cell layer thick, maintained by tight junctions between epithelial cells. When these junctions break down — from reactive foods, gut dysbiosis, stress, or medications including NSAIDs and antibiotics — bacteria, endotoxins, and food proteins enter systemic circulation and trigger widespread immune activation.
Repair is a staged process: first remove the ongoing inflammatory stimulus (reactive foods identified through MRT); then support mucosal healing with L-glutamine (tight junction repair), zinc carnosine (epithelial inflammation reduction), and targeted probiotics; then restore microbiome diversity with prebiotic foods and strain-specific supplementation. Gut epithelial cells turn over every 3–5 days, so structural repair begins quickly once the trigger is consistently removed.
📖 Blog: Leaky Gut — What It Is and How to Repair ItProbiotics add beneficial bacteria — but they can't resolve inflammation driven by a reactive food being consumed every day. Remove the trigger first; probiotics work dramatically better in a calmer gut environment.
When the immune system is continuously activated by reactive foods, gut wall inflammation prevents probiotic bacteria from establishing and thriving — and impairs their production of short-chain fatty acids and mucosal protective compounds.
This is one of the most common patterns we see in practice: clients who've invested in high-quality probiotics with limited results, because the primary inflammatory driver was never identified. Once reactive foods are removed through the LEAP Protocol, probiotics become significantly more effective as part of the microbiome restoration phase. The sequence matters: remove triggers first, support restoration second.
Why partial solutions fail — and what a complete approach looks like →
The gut-brain axis connects gut inflammation directly to mood, cognition, and stress resilience — approximately 90% of the body's serotonin is produced in the gut.
The gut and brain communicate constantly via the vagus nerve, immune signalling, and microbial metabolite production. Gut bacteria produce precursors to serotonin, GABA, and dopamine. When gut inflammation is high — driven by reactive foods or dysbiosis — this production is disrupted, and inflammatory cytokines can cross the blood-brain barrier and directly impact neurotransmitter balance, cortisol regulation, and cognitive function.
When we address gut inflammation and food sensitivities, neurological symptoms — brain fog, anxiety, low mood — consistently improve alongside physical symptoms. For many of our clients, the mood improvements from LEAP are among the most life-changing benefits they report.
How our approach addresses the gut-brain connection in chronic illness →
Chronic stress causes cortisol resistance and immune dysregulation, directly amplifying food-driven and gut-driven inflammation — and independently increasing intestinal permeability.
Acute stress activates cortisol, which initially suppresses inflammation. But chronic stress leads to cortisol receptor desensitization — the immune system stops responding to cortisol's anti-inflammatory signal and becomes dysregulated, producing more inflammatory cytokines. Chronic stress also directly increases intestinal tight junction permeability, worsening the gut-immune cycle driving many chronic conditions.
This is why nervous system regulation is not optional in chronic illness treatment — it's a biological necessity. In every protocol we design, HPA axis support and specific practices that restore vagal tone are addressed alongside food and gut work.
How our full-spectrum approach addresses stress physiology alongside diet →
70–80% of the immune system resides in the gut. Gut barrier dysfunction allows inflammatory triggers into systemic circulation, perpetuating immune activation — and in autoimmune disease, the attack on host tissue.
The gut is the primary site of immune education and tolerance. When intestinal permeability allows food proteins and bacterial components into circulation, sustained immune responses develop. Through molecular mimicry, these immune responses can begin cross-reacting with host tissue that shares similar molecular structures — a mechanism documented in Hashimoto's, rheumatoid arthritis, and other conditions.
Healing the gut and removing food triggers doesn't cure autoimmune disease, but it consistently reduces the immune activation driving it — and works synergistically with medical autoimmune management.
Our approach to supporting autoimmune conditions through gut healing →
Gut epithelial cells turn over every 3–5 days — structural repair begins quickly. Meaningful barrier restoration takes 4–8 weeks; full microbiome rebalancing takes 3–6 months.
The gut's regenerative capacity is remarkable — but only when the inflammatory insult is consistently removed. You cannot heal a wound while continuing to reinjure it. Once reactive foods are eliminated and targeted nutritional support is in place, the process is accelerated: L-glutamine supports tight junction repair, zinc carnosine reduces epithelial inflammation, and prebiotic and probiotic support enables microbiome rebalancing.
Most clients feel meaningful symptom improvement well before the structural healing is complete — often within the first 7–10 days. The deeper healing that prevents relapse simply continues on a longer timeline.
Full guide to the gut healing timeline and what supports repair →
IBS flare-ups are triggered by a combination of food-immune reactivity, gut microbiome disruption, stress physiology, and gut motility dysregulation — but food-driven immune activation is the most commonly missed and most impactful trigger to address first.
The most common IBS flare triggers we identify in practice: specific food sensitivities activating delayed immune responses (independent of fiber or FODMAP content); gut dysbiosis and bacterial overgrowth disrupting motility and fermentation; cortisol and stress hormones directly affecting gut motility and barrier function; and hormonal fluctuations — particularly estrogen — influencing gut reactivity and pain sensitivity.
Why do flares keep returning? Because none of these triggers are addressed by standard IBS management. Low-FODMAP diets remove fermentable carbohydrates but do nothing about immune-mediated protein reactions. Antispasmodics manage symptoms without addressing the cause. Stress management helps but doesn't remove the dietary trigger maintaining the baseline inflammation.
A healthy diet that includes your reactive foods will continue to provoke IBS flares regardless of overall nutritional quality. Food-immune reactivity operates independently of fiber content or FODMAP content — which is why many people with IBS eating very "cleanly" continue to suffer. MRT testing consistently identifies the specific immune trigger that generic IBS advice never addresses.
📖 Blog: What Triggers IBS Flare-Ups? Causes & SolutionsWhy standard IBS dietary advice fails — and what MRT testing reveals instead →
Autoimmune & Immune Conditions
How Food Drives Immune Dysregulation
"Healthy" foods can absolutely trigger your immune system if they're reactive for you individually. Avocado, eggs, salmon, and leafy greens are among the most common MRT-reactive foods in autoimmune clients.
A food's nutritional value and its immunological impact are completely independent. When the gut barrier is compromised — which is common in autoimmune conditions — food proteins enter circulation where the immune system, already primed for reactivity, mounts responses against them. The nutritional quality of the food provides no protection against this.
This is why generic anti-inflammatory diets produce inconsistent results in autoimmune clients: they remove population-level common triggers but miss the individual-specific ones. Personalized MRT testing identifies YOUR specific triggers — which may include foods you'd never suspect and which generic protocols would tell you to eat more of.
How we support autoimmune conditions with personalized food sensitivity testing →
Hashimoto's is an immune condition before it's a thyroid condition. Symptom fluctuations typically track with inflammatory load — often driven by food reactivity extending well beyond gluten.
The good weeks and bad weeks most Hashimoto's clients describe correlate with periods of higher or lower immune activation — influenced by diet, stress, sleep, and hormonal fluctuations. When we identify and remove reactive foods (which in Hashimoto's clients regularly include non-gluten triggers like eggs, dairy, corn, or specific vegetables), the immune environment calms and symptoms stabilize significantly.
The thyroid is reacting to the immune environment around it. Calming that environment — through personalized food sensitivity work and gut healing — is the most direct path to stabilizing both symptoms and thyroid antibody levels over time.
📖 Blog: Hashimoto's and Food Sensitivities — The Missing ConnectionOur approach to Hashimoto's and autoimmune thyroid conditions →
TSH measures pituitary signalling — not thyroid hormone conversion, cellular utilization, or the ongoing immune attack on thyroid tissue that continues regardless of TSH levels.
TSH is a useful screening tool for hypothyroidism but misses critical aspects of thyroid function: free T3 and T4 levels, T4-to-T3 conversion efficiency (impaired by selenium deficiency and chronic inflammation), and cellular thyroid hormone receptor sensitivity. When Hashimoto's is the underlying cause, the autoimmune attack on thyroid tissue continues regardless of what TSH shows.
Additionally, food sensitivities and gut dysfunction affect thyroid function through multiple pathways: impairing absorption of thyroid-critical nutrients (iron, selenium, zinc, iodine), disrupting enterohepatic circulation of thyroid hormones, and maintaining systemic inflammation that dysregulates the entire HPT axis. None of this is captured by TSH — but all of it is addressable through functional testing and the right protocol.
Why functional assessment goes beyond TSH for thyroid health →
Autoimmune medications reduce the intensity of the immune attack — but don't address the food sensitivities, gut dysfunction, and microbiome imbalances continuing to fuel immune activation beneath them.
Immunosuppressants and biologics manage the downstream immune response systemically. What they don't do is investigate or remove the upstream dietary and gut-derived triggers maintaining the immune activation. Food sensitivities, intestinal permeability, and microbiome dysbiosis continue operating independently of medication — which is why many clients on well-managed medical regimens still experience significant residual symptoms.
Our approach works alongside medical treatment, not in place of it. Addressing the dietary and gut factors that conventional autoimmune management doesn't investigate creates a more complete picture — and often produces meaningful additional symptom improvement for clients who felt they had "maxed out" on what medication could do.
Yes. The systemic inflammatory burden created by food sensitivities directly affects joint tissue, synovial fluid, and pain sensitivity — and removing reactive foods consistently reduces joint pain in our clients.
Food-induced immune activation releases inflammatory mediators that circulate systemically, affecting tissues throughout the body including joints. In rheumatoid arthritis, food triggers can amplify the existing autoimmune inflammatory response. In non-autoimmune joint pain, food-driven inflammation contributes to the overall inflammatory burden that makes joints more reactive and painful.
We regularly see clients whose joint pain, stiffness, and swelling decrease substantially after removing reactive foods — sometimes more than they expected, because they hadn't realized how much dietary inflammation was contributing to their joint symptoms.
Fatigue, Brain Fog & Mood
When Exhaustion Has a Root Cause
Persistent fatigue that doesn't improve with rest is almost always driven by an underlying biological cause — food-immune activation, gut dysfunction, nutrient depletion, thyroid dysregulation, or chronic inflammation. It is not a character flaw or a sign of weakness.
The most common root causes we identify in practice: food sensitivities creating continuous immune activation that consumes metabolic energy; gut dysbiosis impairing absorption of B12, iron, magnesium, and other energy-critical nutrients; subclinical thyroid dysfunction that standard TSH testing misses; adrenal/HPA axis dysregulation from chronic stress; and mitochondrial impairment downstream of sustained inflammation.
Inflammatory cytokines (IL-6, IL-1β, TNF-α) directly signal the brain to reduce motivation, increase fatigue drive, and conserve energy — a well-characterized biological phenomenon called sickness behavior. This is biology, not psychology. When the immune system is continuously activated by a reactive food, this signal never turns off.
Standard bloodwork is not designed to detect most of these mechanisms. MRT testing and functional assessment regularly reveal the specific factors that have been driving fatigue for years in people who've been told their labs are fine.
📖 Blog: Why Do I Feel Tired All the Time? Chronic Fatigue Causes & Tips 📖 Blog: Why Your Labs Are Normal But You Still Feel SickHow we investigate and address the root causes of chronic fatigue →
Yes. Post-viral conditions involve persistent immune dysregulation and gut microbiome disruption — the same underlying factors that drive food-sensitivity-related chronic illness — and viral illness can trigger or intensify food sensitivities.
Acute viral illness can disrupt the gut barrier, alter microbiome composition, and prime the immune system for heightened reactivity — all of which increase the likelihood of food sensitivities developing or worsening post-infection. The persistent immune activation, neuroinflammation, and gut dysfunction characteristic of long COVID create conditions where food-driven inflammation becomes a significant and often overlooked contributor to ongoing symptoms.
In our practice, MRT testing in post-viral clients frequently reveals reactive foods contributing to their ongoing fatigue, brain fog, and digestive symptoms. Removing those triggers is often a significant part of their recovery alongside other management strategies.
How food sensitivities drive the fatigue and brain fog of post-viral illness →
Food triggers are a primary driver of migraines — but which foods trigger YOUR migraines is highly individual and often different from standard migraine food lists.
Standard migraine dietary advice focuses on histamine, tyramine, and caffeine as universal triggers. These are population averages — not individual triggers. In our practice, we regularly find migraine clients whose primary triggers are foods considered safe on standard migraine protocols — because MRT measures their specific immune response, not population statistics.
Most clients see significant migraine frequency reduction within 4–6 weeks of following a personalized LEAP Protocol. Some go from weekly migraines to one or two per month; others achieve near-complete resolution. The key insight: consistent migraines usually mean a consistent trigger — and testing identifies it with a precision no elimination diet can match.
How MRT-guided protocols reduce chronic migraine frequency →
Worsening chronic pain is almost always a sign that an underlying inflammatory driver hasn't been identified and removed — not that your condition is untreatable or that you're failing to manage it.
Pain escalation in chronic illness typically reflects one of three patterns: a continuous inflammatory trigger (most commonly a food sensitivity) raising total inflammatory load over time; central sensitization — the nervous system becoming increasingly reactive to the same inputs — which is directly worsened by systemic inflammation; or progressive gut barrier dysfunction that increases the volume of inflammatory compounds entering circulation.
The critical point: pain management strategies (medications, physiotherapy, rest) address the output of the inflammatory process, not the input. When the input is never removed, downstream pain management has a ceiling. Identifying and eliminating food-driven inflammatory triggers — through MRT testing — consistently lowers the baseline pain threshold that all other strategies are working against.
In our practice, clients who have seen their chronic pain worsen over time despite conventional management frequently find that removing reactive foods is the turning point that allows their other treatments to finally produce meaningful results.
📖 Blog: Why Is My Chronic Pain Getting Worse? Causes & SolutionsHow we address the root causes driving chronic pain escalation →
Chronic Skin Conditions
Your Skin Reflects Internal Inflammation
The gut-skin axis describes the direct relationship between gut microbiome health, intestinal permeability, systemic inflammation, and skin barrier function — explaining why so many skin conditions improve when gut inflammation is addressed.
When gut inflammation is high, inflammatory mediators circulate systemically and manifest at the skin as eczema, psoriasis, rosacea, or acne. The skin is often the most visible indicator of systemic inflammatory burden — which is why topical treatments produce incomplete results for conditions with internal inflammatory drivers.
Research has documented gut microbiome differences in eczema, psoriasis, rosacea, and acne patients compared to healthy controls. Addressing the gut-derived inflammation through MRT and LEAP consistently produces skin improvements that topical treatments cannot achieve alone, because we're working upstream of where the skin problem is actually generated.
How we treat chronic skin conditions through gut healing and food sensitivity testing →
Yes — eczema is strongly linked to food sensitivities and gut health. Identifying and removing trigger foods can reduce eczema severity more effectively than topical steroids alone.
The gut-skin axis means eczema with an internal inflammatory component won't fully respond to topical treatment — because the inflammation is being generated internally. Food sensitivities are a significant driver of this internal inflammation: MRT identifies reactions to 176 foods and chemicals, including both obvious triggers and hidden ones that would never be suspected without testing.
Skin improvements typically appear within 2–4 weeks as gut and systemic inflammation decreases. In many of our eczema clients, the improvements from LEAP exceed what years of topical and pharmaceutical management achieved — because for the first time, the actual trigger was identified and removed.
📖 Blog: Food Sensitivities and Eczema — The Gut-Skin ConnectionWhy the foods you eat every day may be driving your skin condition →
Yes. Rosacea has strong gut-skin axis connections — elevated rates of SIBO and gut dysbiosis are documented in rosacea patients, and food-driven immune activation contributes to the systemic inflammation manifesting as flushing and skin barrier breakdown.
Research has identified significantly elevated rates of small intestinal bacterial overgrowth (SIBO) in rosacea patients, and studies have shown rosacea improvement with treatment of the gut condition. Food sensitivities contribute to this picture by sustaining the gut inflammation and systemic immune activation that drives the skin response.
In our practice, identifying and removing reactive foods — alongside gut healing work — consistently reduces rosacea flare frequency and skin reactivity, often significantly more than topical treatments achieve alone. Rosacea is one of the skin conditions most underserved by conventional approaches that don't investigate the gut.
How gut healing and food sensitivity testing address chronic skin conditions →
Adult persistent acne is almost always inflammatory in origin. "Clean eating" staples like eggs, almonds, and certain dairy alternatives are frequently the reactive foods driving it — because they're eaten daily and the delayed reaction is invisible without testing.
The hormonal and inflammatory pathways producing adult acne — androgen sensitivity, sebaceous gland activation, P. acnes proliferation — are all modulated by systemic inflammatory load. Reducing that load through reactive food elimination consistently reduces acne severity.
The pattern we see most often: a client who has been eating very carefully — organic eggs, avocado, almond milk, leafy greens daily — is consuming their primary inflammatory trigger multiple times a day without knowing it. The clean eating framework is nutritionally sound, but it doesn't account for immune reactivity. Testing reveals what the framework can't.
Why "clean eating" doesn't always mean eating right for your immune system →
Pain Conditions
Fibromyalgia, Joint Pain, Migraines & More
Fibromyalgia's hallmark cluster — widespread pain, persistent fatigue, and brain fog — occurs together because all three are downstream of the same mechanism: central sensitization amplified by systemic inflammation, much of which is food-driven.
Fibromyalgia involves central sensitization — a state of nervous system dysregulation in which pain signals are amplified far beyond what the triggering stimulus would normally produce. This explains widespread pain with no identifiable structural damage. But the threshold at which the sensitized nervous system fires is directly influenced by systemic inflammatory load — and food sensitivities are one of the most consistent and modifiable contributors to that load.
The fatigue in fibromyalgia is not simply "being tired" — it is the neurological energy drain of a nervous system in chronic alarm and an immune system in chronic activation. The brain fog reflects the same mechanisms: inflammatory cytokines cross the blood-brain barrier, disrupting neurotransmitter balance and cognitive function. These symptoms occur together because they share the same biological driver.
The most effective solutions in our practice are multimodal: MRT testing to identify and remove food-driven inflammatory triggers; gut healing to address the intestinal permeability contributing to systemic immune activation; targeted nutritional support for magnesium, coenzyme Q10, and B vitamins that are commonly depleted in fibromyalgia; and nervous system regulation work to address the central sensitization directly. Reducing the inflammatory load consistently reduces both the frequency and intensity of fibromyalgia flares — and typically improves pain, fatigue, and brain fog simultaneously.
📖 Blog: Fibromyalgia Symptoms & Solutions: Widespread Pain, Fatigue & MoreHow we support fibromyalgia through inflammation reduction and nervous system work →
Chronic inflammation is a recognized driver of insulin resistance and hormonal dysregulation in PCOS — and food-driven immune activation contributes directly to this inflammatory environment.
Food sensitivities create continuous low-grade immune activation that raises inflammatory markers, disrupts insulin signaling, and affects the gut microbiome in ways that influence estrogen metabolism and hormonal balance. While PCOS is multifactorial, the inflammatory component is significant and modifiable.
In our practice, PCOS clients who complete MRT testing and follow the LEAP Protocol frequently report improvements in cycle regularity, skin symptoms (acne, hirsutism), energy, and weight resistance — alongside improvements in their gut and inflammatory markers.
Our functional approach to hormonal and metabolic conditions →
Food triggers are one of the best-documented drivers of migraines — but the specific foods triggering your migraines are individual, not standard. MRT testing identifies your personal neurological triggers.
The connection between food and migraines is well established in the literature. What is less well understood is that each person's triggers are individual — population-based lists (tyramine, histamine, caffeine) miss the majority of reactive foods for any given person. We frequently identify "unexpected" triggers in migraine clients — foods they eat regularly and consider healthy — that standard migraine diet advice would never suggest removing.
Most clients see significant migraine frequency reduction within 4–6 weeks. For those with near-daily migraines, even reducing frequency by 50–70% is transformative — and many achieve results significantly beyond that.
How MRT pinpoints your individual food triggers for migraines →
Yes. Food-driven immune activation releases inflammatory mediators that circulate systemically and directly affect joint tissue, synovial fluid, and pain sensitivity — removing reactive foods consistently reduces joint pain in our clients.
When it comes to joint pain and arthritis, food triggers amplify the existing autoimmune inflammatory response. The same immune dysregulation attacking joint tissue is often being continuously fuelled by reactive foods that have never been identified. In non-autoimmune joint pain and osteoarthritis, food-driven systemic inflammation contributes to the inflammatory burden that makes joints more reactive, swollen, and painful.
The connection is frequently missed because joint pain is rarely framed as a dietary issue — and because the delayed nature of food sensitivity reactions (2–72 hours) makes the food-to-symptom link invisible without testing. We regularly see clients whose joint stiffness, swelling, and pain decrease substantially after removing reactive foods — often more than they anticipated, because they hadn't realized how large a proportion of their joint inflammation had a dietary driver.
This doesn't mean food is the only factor — structural damage, mechanical loading, and genetics all play a role. But for most clients, food-driven inflammation is a meaningful and modifiable contributor that standard rheumatological care doesn't investigate.
How we address the inflammatory drivers of joint pain and arthritis →
Solutions & Timelines
What Functional Healing Looks Like
Healing isn't linear. Immune recalibration, gut ecology shifts, and nervous system adjustment can all produce temporary symptom worsening in the first days of a new protocol — followed by the improvement most clients experience.
In the early days of an elimination protocol, some clients experience temporary headaches, fatigue, or digestive changes — sometimes called a "healing response." This reflects: inflammatory mediator clearance (the body processing the backlog), gut ecology shifts as microbiome composition begins changing, and blood sugar recalibration if the previous diet was higher in processed foods.
These responses typically resolve within 3–7 days and are followed by the rapid symptom improvement most clients experience. Understanding this prevents people from abandoning an effective protocol before it has time to work. If early responses are significant or prolonged, we troubleshoot together — it's always useful diagnostic information, not a sign to stop.
What to expect during the healing process — and how we support you through it →
LEAP is a phased eating plan built from your individual MRT results — starting with YOUR safest 20–30 foods, not a generic list. This personalization is why it produces faster and more consistent results than standard elimination approaches.
Standard elimination diets remove population-level common culprits — gluten, dairy, soy, eggs — based on averages. They help the people whose triggers happen to be in those categories. They don't help everyone else. LEAP doesn't assume: it starts from actual test results, building your initial diet from the foods your immune system showed the least reactivity to.
This rapid reduction in total reactive food load is why most clients experience about 50% symptom improvement within 7–10 days. LEAP is then systematically expanded as inflammation decreases, with careful reintroduction of moderate and reactive foods over time — restoring dietary variety while maintaining the gains achieved.
Why generic elimination diets fail and how LEAP is different →
The most effective elimination approach is one built from your individual test results — not a generic food list. Personalized protocols consistently outperform population-based approaches.
Standard elimination diets work for people whose triggers align with the populations studied. For everyone else — which is the majority of chronic illness patients — they provide partial or no relief. The investment in MRT testing upfront creates a significantly more efficient and effective healing process than cycling through generic elimination approaches for months or years without resolution.
A detailed breakdown of why elimination diets fail — and what works instead →
Generic elimination diets can accidentally replace reactive foods with other reactive foods the person didn't know about. LEAP avoids this by identifying safest foods first — a controlled, gentler transition.
When people remove common foods (gluten, dairy) without testing, they often replace them with alternatives (almond milk, eggs, certain grains) that happen to be reactive for them individually. The result is a different inflammatory trigger replacing the original one — with no improvement, or even worsening.
LEAP avoids this entirely. Because we know your specific reactivity profile, the initial phase uses only foods confirmed to be in your "green zone." The transition is still an adjustment, but a controlled and comfortable one rather than an unknown substitution game.
The real reason elimination diets backfire — and how to avoid it →
Chronic illness represents years of accumulated inflammatory damage, microbiome disruption, and tissue injury — healing requires reversing all of it, which takes time proportional to how long the damage has been building.
The good news: healing doesn't have to feel slow. Most clients notice meaningful improvement within the first few weeks because removing the primary inflammatory trigger produces rapid results in inflammatory mediator levels. The deeper structural healing simply continues on a longer timeline.
What we tell every client: you didn't develop this condition overnight, and complete healing takes longer than a few weeks. But you will feel significantly better long before the healing is complete — and that early improvement is not just psychological. It's evidence the protocol is working, and it's a preview of where continued healing will take you.
A realistic guide to healing timelines for chronic conditions →
Working With Us
What to Expect When You're Ready to Act
These are the questions people ask when they've moved from "I'm curious" to "I'm ready." Practical, specific answers.
A Certified LEAP Therapist (CLT) with a functional or integrative medicine background is specifically trained to identify and address food-driven chronic inflammation — working at the intersection of immune reactivity, gut function, and chronic symptom resolution.
Unlike conventional dietitians (who focus on general nutrition guidelines) or GPs (who focus on disease management), a CLT is trained specifically in MRT testing interpretation and LEAP Protocol design. The certification requires specialized clinical training — it's not a general nutrition credential.
Megan Pennington is the founder of MP Integrative Health and a Certified LEAP Therapist specializing in chronic symptoms including fatigue, gut issues, autoimmune conditions, and unexplained symptoms. She holds a BSc in Dietetics from McGill University and has over 20 years of clinical experience. Our team of practitioners — personally trained by Megan — work with clients across the USA and Canada via virtual consultation.
The first appointment is a comprehensive intake — your complete health history, symptoms, previous treatments, and goals. We discuss whether MRT testing is right for your situation, and there is no commitment required.
We spend the intake session building a full picture of your health: symptom timeline, what you've tried, what partially worked, current diet, stress level, medications, and what you're hoping to achieve. This gives us the context to discuss whether MRT testing is appropriate and what a personalized protocol would involve for your specific situation.
If you proceed with testing, a blood kit is arranged and results typically return within 10–14 days. The follow-up appointment then builds your personalized LEAP Protocol from your results. The first session is about understanding your situation and determining whether our approach is the right fit — not a sales process.
It depends on the extent of restriction. MRT measures your current immune reactivity — foods not recently eaten may show artificially low reactivity. For most partial elimination diets, testing is still highly informative.
For people on partial elimination diets (e.g., gluten-free but otherwise varied), testing is still highly informative — the majority of the 176 foods tested will have been consumed recently enough for accurate results. For very restrictive diets, we discuss the best approach in the initial consultation. In some cases, a brief and strategic reintroduction period before testing provides more complete results.
The key principle: MRT measures what your immune system is currently reactive to, based on recent exposure. We factor that into test interpretation and protocol design. It's always better to test and work with the information available than to delay indefinitely.
MRT is generally not covered by standard insurance, but may be partially reimbursable through HSA or FSA accounts. We provide detailed receipts to support any submissions.
MRT testing is classified as a specialty functional test rather than a standard diagnostic test, which places it outside most standard insurance coverage in the US and Canada. Some clients are able to submit for partial reimbursement through Health Savings Accounts (HSA) or Flexible Spending Accounts (FSA) — we provide detailed receipts to support those submissions.
It helps to think about the cost in context: many clients have spent years and significant money on treatments that addressed symptoms without finding the cause. The upfront investment in testing typically replaces rather than adds to that ongoing expenditure — because once triggers are identified, the trial-and-error cycle can finally stop.
MRT testing costs, insurance, and what's included in our programs →
In over 20 years of practice, when LEAP produces slower results than expected, there is almost always a specific, identifiable reason — and we investigate it systematically rather than abandoning the approach.
The most common reasons results are slower than expected: an additional trigger not captured by food testing (sometimes environmental or chemical), a significant gut integrity issue requiring more intensive repair work before dietary changes take full effect, or a compliance challenge we can troubleshoot together. None of these are dead ends — they're information that guides the next step.
We don't work with everyone. If your situation requires a level of medical management that goes beyond our scope, we'll communicate that clearly and refer appropriately. But for the overwhelming majority of clients with food-driven chronic inflammation, the protocol produces meaningful results — and when progress is slower than expected, we investigate why rather than giving up.
Still have a question not answered here? Every person's situation is unique. An introductory consultation lets us apply this thinking directly to your specific symptoms, history, and goals — with no commitment required. Book a free intro call →
Megan Pennington, BSc, CLT
Founder, MP Integrative Health · Integrative Health Practitioner · Certified LEAP Therapist
Megan Pennington is the founder of MP Integrative Health and an integrative health practitioner with over 20 years of clinical experience. She specializes in chronic symptoms — including unexplained fatigue, digestive issues, autoimmune conditions, skin conditions, and symptoms that standard medicine hasn't been able to explain.
Her approach combines root-cause analysis using advanced functional testing — including MRT food sensitivity testing — with personalized healing protocols designed around each client's unique biochemistry. She holds a BSc in Dietetics and Human Nutrition from McGill University, is a Certified LEAP Therapist (CLT), and is a 2025 Global Recognition Award Winner for Advancing Science-Based Natural Healing.
MP Integrative Health provides virtual consultations for clients across the USA and Canada. Clients work with a designated practitioner personally trained by Megan using her clinical protocols.
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