Coeliac, Deamidated Gliadin Peptide Antibodies

The Deaminated Gliadin Peptide (DGP) Antibodies test detects antibodies your immune system produces in response to deamidated gliadin peptides—fragments of gluten proteins found in wheat, barley, and rye. These antibodies (either IgA or IgG) are key indicators of an abnormal immune response to gluten.

This test helps identify coeliac disease, an autoimmune condition where gluten triggers inflammation and damage to the small intestine, impairing nutrient absorption. Like most auto-antibodies, having a positive result does not necessary equal a diagnosis: some healthy individuals will have a positive result with no real implication.

High levels of DGP antibodies suggest the immune system is reacting to gluten, which may lead to intestinal inflammation.

Over time, this can cause:

• Nutrient malabsorption (iron, folate, vitamin D, calcium)

• Fatigue, anaemia, bloating, and digestive pain

• Poor bone density and hormonal imbalances

• Increased risk of other autoimmune conditions
  

Detecting DGP antibodies early helps identify gluten-related autoimmunity before irreversible intestinal damage occurs.

In clinical practice, DGP testing is often paired with tTG antibodies to improve diagnostic accuracy — and reduce the need for invasive intestinal biopsy.

Levels of DGP antibodies can rise or fall depending on:

• Gluten intake: Even small amounts of gluten can elevate DGP antibodies in coeliac disease.

• Dietary changes: Adopting a gluten-free diet typically lowers antibody levels over weeks to months.

• Immune activity: Infections or autoimmune flare-ups may temporarily influence antibody production.

• IgA deficiency: In people with low IgA, DGP-IgG may be the only elevated marker.

• Testing timing: If you’ve been gluten-free for a while, antibody levels may normalize — masking disease activity unless gluten exposure resumes.

If DGP antibodies are elevated:

1. Consult your clinician — further testing (tTG antibodies, HLA typing, or intestinal biopsy) may be recommended for confirmation.
   

2. Do not eliminate gluten prematurely before completing diagnostic tests, as this can reduce antibody levels and affect results.
   

3. Once confirmed, your medical clinician may advise to adopt a medically supervised gluten-free diet, avoiding wheat, barley, rye, and contaminated foods.
   

4. Re-test after 6-12 months to monitor antibody normalisation.
   

5. Support recovery with nutrient-dense foods and supplementation for common deficiencies (iron, vitamin D, B12, folate, calcium).
   

6. Address gut repair and microbiome balance — guided by your clinician — to restore healthy intestinal function.

For individuals with coeliac disease or gluten intolerance, some grains are significantly better choices than others. The cornerstone of management is a lifelong, strict gluten-free diet that excludes wheat, rye, and barley. Fortunately, a number of gluten-free grains and pseudo-cereals—such as quinoa, amaranth, buckwheat, millet, and sorghum—offer excellent nutritional value. These grains are naturally rich in protein, fibre, B-complex vitamins, minerals, and healthy unsaturated fats, helping to improve the nutrient density of a gluten-free diet and support overall gut and metabolic health.

Pure, uncontaminated oats are also well tolerated by most people with coeliac disease and can contribute valuable fibre and micronutrients. It is, however, essential to confirm that oats are certified gluten-free to avoid cross-contamination during processing, which is a common source of inadvertent gluten exposure.

When selecting gluten-free foods, whole-grain and minimally processed options should always take priority. Many processed gluten-free products have a higher glycaemic index and lower nutritional quality compared with their whole-food counterparts. To counter common nutrient shortfalls associated with gluten-free diets—particularly fibre, iron, calcium, magnesium, and B-vitamins—it’s best to include a variety of whole gluten-free grains, legumes, nuts, seeds, leafy greens, seafood, and fortified foods.

For everyday practical use, choose certified gluten-free flours and grains, carefully read labels for “may contain gluten” or shared-line warnings, and rotate your grain choices to keep the diet diverse and nutritionally complete. Dishes such as quinoa bowls, buckwheat soba, millet pilafs, and sorghum porridges are simple ways to incorporate variety. If symptoms persist despite dietary vigilance, clinicians may recommend repeating laboratory tests—such as iron studies, vitamin B12 and folate, vitamin D, calcium, or follow-up coeliac serology—to check for hidden deficiencies or ongoing inflammation.

Gluten intolerance has been recognised for centuries. As early as the 1st–2nd century CE, Aretaeus of Cappadocia described a “coeliac” wasting illness that matches modern descriptions of coeliac disease. In 1888, British physician Samuel Gee was the first to formally link the condition to diet. A major breakthrough came during World War II, when Dutch paediatrician Willem-Karel Dicke observed that children with coeliac disease improved during wartime bread shortages and relapsed when wheat returned to the diet—leading to the discovery that gluten was the culprit.

By the mid-20th century, small-bowel biopsies confirmed the intestinal damage caused by gluten, and in the modern era, diagnostic advances such as tTG and DGP antibody testing and HLA genotyping have transformed both diagnosis and disease monitoring. These developments have turned what was once a mysterious, debilitating condition into one that is now widely recognised, accurately diagnosed, and effectively managed through informed dietary intervention.

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