“The path to a healthier diet may begin by identifying foods that actually cause your symptoms of illness”
– eeMD

Food Intolerance & Sensitivity – An Overview



Food Sensitivity:

A catch-all term for conditions which result in symptoms due to ingestion of a food or nutrient, regardless of the mechanism by which the symptoms occur.


Food Intolerance:

Symptoms resulting from the inability to digest/metabolize a food or nutrient – symptoms that are usually limited to the gastrointestinal (GI) tract.


Food Hypersensitivity:

An immune/allergic response to a food or nutrient that causes gastrointestinal (GI) symptoms and/or systemic symptoms.



Food Intolerance & Sensitivity: Gluten

Elimination Diet – Gluten

Elimination Diet – FODMAPs

Irritable Bowel Syndrome (IBS)

See also:

Diet & Diets

Diet & Pain: An Overview

Diet & Fibromyalgia

Antioxidants and Oxidative Stress

NRF2 Activators

Nutrition: Amino Acids

Nutrition: Carbohydrates


Wellness/Anti-Inflammatory Diets (coming soon):

Mediterranean Diet

Paleo Diet

Okinowan Diet



Diet Supplements:

Supplements – An Overview


NRF2 Activators

Mitochondrial Dysfunction



Key to Links:

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Red text – another page on this website

Blue text – Journal publication




Food Intolerance & Sensitivity

Specific foods can play a significant role in the health of certain individuals, leading to a wide range of mild to severely incapacitating symptoms, including gastrointestinal symptoms, neurological symptoms, fatigue and, importantly, pain. These symptoms may be the consequence of: 1. a food intolerance (impaired digestion of a particular food or nutrient); 2. a food hypersensitivity (an immune system-based allergic or antibody response to a food or nutrient) or; 3. a nonspecific food sensitivity due to unknown mechanisms.


The gold standard diagnosis for intolerance or sensitivity to a food is by elimination and reintroduction. Intolerance or sensitivity is demonstrated if symptoms resolve on elimination and reappear on reintroduction.

1. Food Intolerance – Digestion and Metabolism Related

Food intolerance is related to the inability to properly digest or metabolize a food or nutrient. Food intolerance is not uncommon and includes lactose intolerance (due to insufficient lactase enzyme) and histamine & tyramine intolerance (related to genetics or metabolic overload). Intolerance of certain sugars and fibers called FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) is not uncommon and may be the source of symptoms in some people with Irritable Bowel Syndrome (IBS) and fibromyalgia.


Symptoms related to food intolerance  are usually limited to gastrointestinal (GI) complaints such as abdominal pain or cramps, bloating, flatulence, nausea and diarrhea.


Food Intolerance: Lactose

Lactose intolerance is the impaired ability to digest the milk sugar, lactose, found in dairy products. Lactose intolerance is associated with intestinal symptoms such as bloating, cramps and diarrhea. This diagnosis can usually be established by identifying these symptoms when ingesting dairy products. It can be definitively diagnosed by a breath hydrogen test after lactose administration. Unlike gluten sensitivity, however, lactose intolerance does not give rise to systemic or non-intestinal symptoms.


Food Intolerance: FODMAPs

FODMAPs (Fermentable Oligo-Di-Mono saccharides And Polyols). are a group of small chain carbohydrates (sugars and fibers) that are commonly found in everyday foods such as: wheat, barley, rye, apples, pears, mango, onion, garlic, honey, kidney beans, cashew nuts, agave syrup, sugar free gum, mints and some medicines.

See: Samples of high FODMAP food sources


In those people afflicted with intolerance to FODMAPs, FODMAPs are resistant to digestion and are poorly absorbed in the proximal small intestine but are digested by bacteria in the distal small intestine and colon. It is  believed that FODMAPs trigger gastrointestinal (GI) symptoms by inducing intestinal distension via a combination of osmotic effects and gas production because they provide a substrate for bacterial fermentation in the small and large intestine.


As a consequence of their resistance to digestion in the proximal small bowel, FODMAPs contribute to abdominal symptoms such as bloating, abdominal cramps and pain, constipation, diarrhea and flatulence, symptoms similar to gluten sensitivity. Because of the overlapping presence of both gluten and FODMAPs in wheat, barley and rye,  some cases of non-celiac gluten sensitivity (NCGS) may actually be FODMAP sensitivity (see below).



Symptoms of Irritable Bowel Syndrome (IBS) may be indistinguishable for FODMAP intolerance. In fact, up to 75% of those who suffer with IBS will benefit from dietary restriction of FODMAPs. Research has shown that a low FODMAP diet improves GI symptoms including gas, bloating, abdominal pain and cramps and changes in bowel habits related to IBS.

See: IBS


Not all bad…

While FODMAPs can cause GI symptoms in intolerant individuals, they also inhibit, rather than cause, intestinal inflammation and induce beneficial alterations in intestinal microbiota (microbiome) and generate healthful short-chain fatty acids.

Food Hypersensitivity – Immune-related

Intolerance to food can be immune-related, the result of a reaction to either IgE or IgG antibodies. IgE antibody reactions result in typical, immediate-onset allergic reactions characterized by hives and/or life-threatening anaphylaxis. IgG antibody reactions (technically not allergic reactions) are more subtle and avoid obvious recognition in many cases. Immune-related food intolerances can be tested for by measuring IgE and/or IgG antibody levels for various foods commonly associated with intolerances. However, IgG testing is not very specific in identifying food sensitivities and may lead to incorrect conclusions. When foods are identified by IgG testing as likely to trigger a food sensitivity, an elimination diet can be performed to eliminate the suspicious foods and monitor for symptoms associated with elimination and reintroduction of the foods.

See: Example of IgG Food Antibody Test


Food Hypersensitivity Wheat Allergy

Somewhat uncommon, wheat hypersensitivity is characterized by an immune antibody (IgE) mediated response against a variety of wheat components resulting in respiratory symptoms or gastrointestinal symptoms.  Symptoms related to wheat hypersensitivity may overlap with those of gluten hypersensitivity. Gluten hypersensitivity is due to a reaction to gluten, a protein found not just in wheat but in other grains as well.


In addition, a non-immunoglobulin E (IgE)-mediated wheat allergy also occurs, with different systemic and GI symptoms, similar to Celiac disease (gluten hypersensitivity) and Non-Celiac Gluten Sensitivity (NCGS) in terms of quality and time of onset.

The components of wheat flour responsible for wheat hypersensitivity belong to the family of amylase-trypsin inhibitors (ATIs) that trigger toll-like receptor 4 (TLR-4) which release of pro-inflammatory cytokines (peptides). ATIs are not classified as gluten proteins and plants other than wheat also contain ATIs but show only minimal or no TLR4-activity and are not associated with sensitivities. Thus individuals with wheat sensitivity only will tolerate other grains with gluten, just not wheat.


Tests for Wheat Allergy

If one’s history suggests allergy to wheat, a skin prick test can be performed in which a series of skin pricks are placed usually in the inner forearm. The test measures IgE antibodies that are released from mast cell causing a localized area of redness, swelling and itching which indicates a positive test for wheat allergy. The results of this test are evident in less than an hour from placement.


An alternative to the skin prick test is a blood test that also measures IgE antibodies. Results are usually available in 7-14 days and can be classified as negative or minor sensitivity up to extremely high sensitivity. Unfortunately neither the skin prick or blood test are reliably sensitive or accurate and may provide misleading and false results.

Food Sensitivity Gluten

Gluten is a protein found in wheat, rye, and barley. In sensitive individuals, ingestion of gluten gives rise to a wide range of gastrointestinal, systemic and/or behavioral symptoms. Gluten sensitivity has a wide spectrum of severity; Celiac Disease (CeD has potentially the most severe symptoms, while other non-celiac gluten sensitivity (NCGS) syndromes may only have mild gastrointestinal symptoms. Patients with FM may have coexisting CeD or NCGS or neither, but sensitivity to gluten is not uncommon in FM patients.

See: Food Intolerance & Sensitivity: Gluten


Celiac Disease (CeD)

Sensitivity to dietary glutens is commonly associated with Celiac Disease (CeD – also known as celiac sprue and gluten-sensitive enteropathy) an autoimmune disease that affects the small intestine. Exposure to gluten triggers an inflammatory response in the small intestinal mucosa, which interferes with the absorption of nutrients and leads to nutritional deficiencies and gastrointestinal, systemic and behavioral symptoms.


It can be diagnosed with blood tests for specific antibodies and sometimes may require intestinal biopsy for confirmation testing. In most cases, CeD can be successfully treated with a gluten-free diet.


Non-Celiac Gluten Sensitivity (NCGS)

Non-Celiac Gluten Sensitivity (NCGS) is also known as gluten sensitivity and non-celiac gluten intolerance.  While there is no agreed-upon definition of NCGS, it can be described as a condition in which ingestion of foods containing gluten (wheat, rye, and barley) leads to one or more of a variety of symptoms in people in whom wheat allergy and CeD has been excluded. Furthermore, these symptoms resolve with elimination of gluten from the diet and recur after gluten is reintroduced into the diet.


Patients with NCGS may experience either intestinal and/or non-intestinal symptoms with ingestion of gluten. Intestinal symptoms include diarrhea, abdominal discomfort or pain, bloating, and flatulence) and extra-intestinal symptoms include headache, lethargy, attention-deficit/hyperactivity disorder, skin manifestations, or recurrent oral ulcerations.


Diagnosis of Gluten Sensitivity

For those people with symptoms consistent with gluten sensitivity, screening for Celiac disease can be performed with blood tests. For those with severe symptoms and high suspicion for Celiac disease, it may be necessary to perform an intestinal biopsy to identify the diagnosis in the presence of negative blood testing.

See: Food Intolerance & Sensitivity: Gluten


However, the diagnosis of NCGS is highly presumptive due to lack of a reliable diagnostic test. In order to identify gluten sensitivity, dietary elimination of gluten to observe for improvement of symptoms is advised.

See: Elimination Diet: Gluten

Additionally, IBS symptoms may be difficult to distinguish from gluten sensitivity and, in fact while the symptoms of these two conditions overlap, both conditions may also coexist in the same person. Studies indicate that about 50% of those with IBS have improvement of symptoms with a gluten-free diet.

Treatment of Gluten Sensitivity

For those with Celiac Disease and severe gluten sensitivity, the only treatment is lifelong avoidance of gluten; even small amounts of gluten cause intestinal damage. Adherence to a gluten-free diet is difficult, especially since food processing can add gluten to foods that would otherwise be considered safe. For example, while potatoes are safe, depending on the processing used to prepare them, french fries may not be safe. More problematic for complete avoidance are the less well-known inclusions of gluten in some prescription or over-the-counter medicines and other commonly encountered products, even stamp and envelope adhesive.

See: Food Intolerance & Sensitivity: Gluten


Who Should Do a Trial of a Gluten-Free/FODMAP-Free Diet?

Since FODMAP intolerance generally results in symptoms limited to the GI tract, it would be argued that only patients with significant impact of GI symptoms consider a FODMAP-free diet. Thus, those with GI complaints that are frequent, chronically recurrent and that may include abdominal bloating, flatulence, cramps, abdominal pain, diarrhea, constipation, nausea, or loss of appetite should consider a 3-4 week elimination diet to identify if eliminating these foods results in a reduction of the GI symptoms suffered. 


Since gluten hypersensitivity that is a result of Celiac disease (CeD)  has a known auto-immune basis, anyone with blood tests and/or intestinal biopsy findings consistent with CeD should absolutely do an extended trial of a gluten-free diet (GFD). It may takes weeks or even up to a year to experience the full benefit of the GFD in those with CeD. Blood tests can be performed to monitor antibody levels to track an individual’s response .


At present, there are no defined predictors of response to a gluten-free diet in patients with symptoms of IBS or non-celiac gluten sensitivity (NCGS). Furthermore, there is no diagnostic marker for NCGS and the diagnosis is confirmed only when symptoms improve with a gluten-free diet and symptoms reappear with addition of gluten back into the diet. Therefore, for those with FM who test negative for CeD, there is no specific test that can otherwise be performed to determine if gluten hypersensitivity is contributing to symptoms attributed to FM, including both systemic and/or gastroeintestional.


For this reason, it is advisable that anyone with FM symptoms that significantly impacts their quality of life, likely most everyone with FM, should consider a trial of a GFD for 3-4 weeks. If there is no significant benefit achieved with a trial GFD, the question of possible gluten hypersensitivity as a contributor to one’s symptoms is excluded.



Food Intolerance & Sensitivity: Gluten

Elimination Diet – Gluten

Elimination Diet – Fibromyalgia


Fibromyalgia and Food Sensitivity

Foods implicated in the symptoms of fibromyalgia include gluten, neuroexcitatory agents such as monosodium glutamate (MSG), and FODMAPs (Fermentable Oligo-Di-Mono-saccharides And Polyols), sugars found in a number of foods. Engaging an Elimination Diet in which suspicious foods are removed from the diet to determine their impact of FM symptoms can identify the culprit foods and potentially lead to a dietary approach that can seriously improve quality of life for some FM patients.

See: Diet & Fibromyalgia



Diet – Fibromyalgia


FM – Nutrition Overview

  1. Fibromyalgia – Diet & CAM Summary
  2. Fibromyalgia and nutrition – what news? – 2015
  3. Nutrition and Supplements for Fibromyalgia
  4. Modulation of NMDA Receptor Activity in Fibromyalgia – 2017


FM – Diet – Overviews

  1. 5 Ways To Control Fibromyalgia With Diet – 2013
  2. Fibromyalgia and nutrition, what do we know? – PubMed – NCBI – 2010
  3. Dietary aspects in fibromyalgia patients: results of a survey on food awareness, allergies, and nutritional supplementation. – PubMed – NCBI
  4. Neurobiology of fibromyalgia and chronic widespread pain. – PubMed – NCBI
  5. Fibromyalgia and nutrition: what news? – PubMed – NCBI
  6. Gluten-free diet in the management of patients with irritable bowel syndrome, fibromyalgia and lymphocytic enteritis – 2014
  7. Influence of pro-algesic foods on chronic pain conditions. 2016 – PubMed – NCBI


FM & Diet – Excitotoxins: Aspartame & MSG (glutamate)

  1. Aspartame-induced fibromyalgia, an unusual but curable cause of chronic pain. – PubMed – NCBI
  2. Relief of Fibromyalgia Symptoms Following Discontinuation of Dietary Excitotoxins – 2000
  3. Hidden Sources Of MSG And Aspartame In Foods
  4. the-effect-of-dietary-glutamate-on-fibromyalgia-and-irritable-bowel-symptoms
  5. The effect of dietary glutamate on fibromyalgia and irritable bowel symptoms. – PubMed – NCBI
  6. Relief of fibromyalgia symptoms following discontinuation of dietary excitotoxins. 2001 – PubMed – NCBI
  7. Monosodium glutamate and aspartame in perceived pain in fibromyalgia. 2014 – PubMed – NCBI
  8. Influence of pro-algesic foods on chronic pain conditions. 2015- PubMed – NCBI
  9. High-Intensity Sweeteners Permitted for use in Food in the United States (FDA)
  10. MSG – Questions and Answers on Monosodium glutamate (FDA)

FM & Diet – FODMAPs

  1. A low fermentable oligo-di-mono saccharides and polyols (FODMAP) diet reduced pain and improved daily life in fibromyalgia patients. – PubMed – NCBI
  2. A low fermentable oligo-di-mono-saccharides and polyols (FODMAP) diet is a balanced therapy for fibromyalgia with nutritional and symptomatic benefits – PubMed – NCBI
  3. Low FODMAPs diet vs. general dietary advice improves clinical response in patients with diarrhea-predominant irritable bowel syndrome: a randomized… – PubMed – NCBI
  4. Low-FODMAP Diet Improves Irritable Bowel Syndrome Symptoms – A Meta-Analysis – 2017
  5. Polyphenol-Rich Foods Alleviate Pain and Ameliorate Quality of Life in Fibromyalgic Women. – PubMed – NCBI
  6. The Low FODMAP Diet – Many Question Marks for a Catchy Acronym – 2017
  7. Does a diet low in FODMAPs reduce symptoms associated with functional gastrointestinal disorders

FM & Diet – FM and Irritable Bowel Syndrome (IBS)

  1. Effect of one year of a gluten-free diet on the clinical evolution of irritable bowel syndrome plus fibromyalgia in patients with associated lymphocytic enteritis – 2014
  2. Gluten-free diet in the management of patients with irritable bowel syndrome, fibromyalgia and lymphocytic enteritis – 2014
  3. The Overlap between Irritable Bowel Syndrome and Non-Celiac Gluten Sensitivity – A Clinical Dilemma – 2015

FM & Diet – Gluten: FM and Celiac Disease

  1. Clinical impact of a gluten-free diet on health-related quality of life in seven fibromyalgia syndrome patients with associated celiac disease

FM & Diet – Gluten: Non-Celiac Gluten Sensitivity (NCGS)

  1. Nonceliac gluten sensitivity. – PubMed – NCBI
  2. Non-celiac gluten sensitivity – Time for sifting the grain – 2015
  3. Non-celiac gluten hypersensitivity. – PubMed – NCBI
  4. The Overlap between Irritable Bowel Syndrome and Non-Celiac Gluten Sensitivity – A Clinical Dilemma – 2015
  5. Non-celiac Gluten Sensitivity. Is it in the Gluten or the Grain? – 2013
  6. Fibromyalgia and non-celiac gluten sensitivity – a description with remission of fibromyalgia – 2014
  7. The Effects of a Gluten-free Diet Versus a Hypocaloric Diet Among Patients With Fibromyalgia Experiencing Gluten Sensitivity-like Symptoms: A Pilot… – PubMed – NCBI
  8. Gluten-free diet in the management of patients with irritable bowel syndrome, fibromyalgia and lymphocytic enteritis – 2014

FM & Diet – Obesity

  1. Fibromyalgia and obesity: the hidden link. – PubMed – NCBI


Gluten: Celiac Disease

  1. Update on Celiac Disease – New Standards and New Tests – Algorithm
  3. Benefits of a gluten-free diet for asymptomatic patients with serologic markers of celiac disease. – PubMed – NCBI
  4. Coeliac disease -2008-Leeds
  5. Diagnosis and management of adult coeliac disease – guidelines from the British Society of Gastroenterology

Gluten: FM and Celiac Disease

  1. Clinical impact of a gluten-free diet on health-related quality of life in seven fibromyalgia syndrome patients with associated celiac disease

Gluten: Non-Celiac Gluten Sensitivity (NCGS)

  1. Nonceliac gluten sensitivity. – PubMed – NCBI
  2. Non-celiac gluten sensitivity – Time for sifting the grain – 2015
  3. Non-celiac gluten hypersensitivity. – PubMed – NCBI
  4. The Overlap between Irritable Bowel Syndrome and Non-Celiac Gluten Sensitivity – A Clinical Dilemma – 2015
  5. Non-celiac Gluten Sensitivity. Is it in the Gluten or the Grain? – 2013
  6. Fibromyalgia and non-celiac gluten sensitivity – a description with remission of fibromyalgia – 2014
  7. The Effects of a Gluten-free Diet Versus a Hypocaloric Diet Among Patients With Fibromyalgia Experiencing Gluten Sensitivity-like Symptoms: A Pilot… – PubMed – NCBI
  8. Gluten-free diet in the management of patients with irritable bowel syndrome, fibromyalgia and lymphocytic enteritis – 2014
  9. Non-coeliac-gluten-sensitivity – A-new-disease-with-gluten-intolerance-2015
  10. The Overlapping Area of Non-Celiac Gluten Sensitivity (NCGS) and Wheat-Sensitive Irritable Bowel Syndrome (IBS) – 2017

Diet – Water

  1. Water, Hydration and Health – 2010
  2. healthy_hydration_toolkit_march_2015

Fast Eating

  1. Self-reported faster eating associated with higher ALT activity in middle-aged, apparently healthy Japanese women. – PubMed – NCBI
  2. Self-awareness of fast eating and its impact on diagnostic components of metabolic syndrome among middle-aged Japanese males and females. – PubMed – NCBI
  3. Self-reported faster eating is positively associated with accumulation of visceral fat in middle-aged apparently healthy Japanese men. – PubMed – NCBI
  4. Association Between Eating Speed and Metabolic Syndrome in a Three-Year Population-Based Cohort Study – 2015
  5. Self-reported eating rate and metabolic syndrome in Japanese people – cross-sectional study -2014

Eating – Appetite, Satiation and Pain

  1. Decreased food pleasure and disrupted satiety signals in chronic low back pain. – PubMed – NCBI

The Microbiome – Overview


The Microbiome – Arthritis and Rheumatic Diseases

  1. Microbiome in Inflammatory Arthritis and Human Rheumatic Diseases – 2017
  2. A Possible Role of Intestinal Microbiota in the Pathogenesis of Ankylosing Spondylitis – 2016
  3. Hypothesis – Time for a gut check – HLA B27 predisposes to ankylosing spondylitis by altering the microbiome

The Microbiome – Inflammatory Bowel Disease

  1. The microbiota in inflammatory bowel disease – current and therapeutic insights – 2017
  2. Diet in the Pathogenesis and Treatment of Inflammatory Bowel Diseases – 2015

The Microbiome – Obesity

  1. Innate sensors of pathogen and stress: linking inflammation to obesity. – PubMed – NCBI
  2. Microbiota, inflammation and obesity. – PubMed – NCBI
  3. Obesity-Driven Gut Microbiota Inflammatory Pathways to Metabolic Syndrome – 2015
  4. Gut microbiota as a key player in triggering obesity, systemic inflammation and insulin resistance. 2014 – PubMed – NCBI

The Microbiome – Opioids

  1. Chronic Opioid Use Is Associated With Altered Gut Microbiota and Predicts Readmissions in Patients With Cirrhosis – 2017
  2. Opioid-induced gut microbial disruption and bile dysregulation leads to gut barrier compromise and sustained systemic inflammation – 2016

The Microbiome – Probiotics

  1. A Gastroenterologist’s Guide to Probiotics – 2012
  2. Probiotic Candian Clincial Guide to Probiotics

The Microbiome – Pain

  1. The gut microbiota as a key regulator of visceral pain – 2017

The Microbiome – Surgery

  1. Gut microbiome, surgical complications and probiotics – 2017

Food Sensitivities – Overviews


Food Sensitivities – Gluten

  1. Non-coeliac-gluten-sensitivity-e-A-new-disease-with-gluten-intolerance-2015


  1. Kaempferol, a dietary flavonoid, ameliorates acute inflammatory and nociceptive symptoms in gastritis, pancreatitis, and abdominal pain. – PubMed – NCBI
  2. Advanced Glycation End Products in Foods and a Practical Guide to Their Reduction in the Diet – 2010

Obesity – Pain

  1. Obesity-related adipokines predict patient-reported shoulder pain – 2013
  2. Adipokine Contribution to the Pathogenesis of Osteoarthritis – 2017
  3. Relationship between Neuropathic Pain and Obesity – 2016
  4. “The more pain I have, the more I want to eat” – obesity in the context of chronic pain – 2012
  5. Weight loss – the treatment of choice for knee osteoarthritis? A randomized trial – 2004


Emphasis on Education


Accurate Clinic promotes patient education as the foundation of it’s medical care. In Dr. Ehlenberger’s integrative approach to patient care, including conventional and complementary and alternative medical (CAM) treatments, he may encourage or provide advice about the use of supplements. However, the specifics of choice of supplement, dosing and duration of treatment should be individualized through discussion with Dr. Ehlenberger. The following information and reference articles are presented to provide the reader with some of the latest research to facilitate evidence-based, informed decisions regarding the use of conventional as well as CAM treatments.


For medical-legal reasons, access to these links is limited to patients enrolled in an Accurate Clinic medical program.


Should you wish more information regarding any of the subjects listed – or not listed –  here, please contact Dr. Ehlenberger. He has literally thousands of published articles to share on hundreds of topics associated with pain management, weight loss, nutrition, addiction recovery and emergency medicine. It would take years for you to read them, as it did him.


For more information, please contact Accurate Clinic.


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