Celiac Disease: A Complete Guide by a Brazilian Nutritionist Who Lives It

If you’re a Brazilian living abroad and have been diagnosed with celiac disease — or suspect you might have it — this guide is for you. As a Brazilian nutritionist who is herself celiac, I understand the unique challenges of managing this condition far from home: navigating unfamiliar food labels, missing pão de queijo, finding safe options at restaurants, and dealing with healthcare systems in a different language. This is the comprehensive guide I wish I’d had when I was first diagnosed.

By Taissa Castello, registered nutritionist CRN-4 25106120, specialized in celiac disease, food allergies, and gut health.

What is celiac disease?

Celiac disease is an autoimmune condition triggered by gluten — a protein found in wheat, rye, and barley — in genetically predisposed individuals. When someone with celiac disease eats gluten, their immune system attacks the lining of the small intestine, damaging the villi (tiny finger-like projections responsible for nutrient absorption). This leads to malabsorption, nutritional deficiencies, and a wide range of symptoms that go far beyond digestive issues (Rubio-Tapia et al., 2023).

Unlike a food allergy or gluten sensitivity, celiac disease involves a specific autoimmune mechanism: the body produces antibodies (anti-tissue transglutaminase and anti-endomysial) that attack the intestinal mucosa. It affects approximately 1-2% of the global population, but the vast majority remain undiagnosed — including many Brazilians living abroad who may attribute their symptoms to stress, dietary changes, or “just getting used to the food here” (Caio et al., 2019).

“Celiac disease happens when a person eats gluten and, if they have a genetic predisposition, they can develop this autoimmune condition. No human being can fully digest gluten — neither celiac nor non-celiac. About 40% of the world’s population carries the genetics for celiac disease, but only 1-2% actually develop it.”

— Taissa Castello, PodIgest Ep. 3

Why this matters for Brazilians abroad

Brazil has specific laws protecting celiac consumers — Lei 10.674/2003 requires all food products to clearly state whether they contain or may contain gluten. When you move to the US, UK, Europe, or Australia, the labeling rules are different. Some countries are better (the EU has strict allergen regulations), while others leave more room for confusion.

Additionally, many Brazilian comfort foods are naturally gluten-free — tapioca, pão de queijo (made with polvilho), cuscuz de milho, farofa de mandioca. Abroad, you might find yourself surrounded by wheat-heavy cuisines (bread, pasta, pastries) and missing the familiar safe options. Understanding what’s safe in your new food environment is crucial.

Symptoms: beyond the obvious

Celiac disease is often called “the great mimicker” because its symptoms extend far beyond digestive issues. While bloating, diarrhea, abdominal pain, and weight loss are the classic signs, many adults — especially those diagnosed later in life — present primarily with extraintestinal symptoms:

• Chronic fatigue — unexplained tiredness that doesn’t improve with rest
• Iron-deficiency anemia — resistant to oral iron supplementation
• Bone pain / osteoporosis — due to calcium and vitamin D malabsorption
• Skin rash (dermatitis herpetiformis) — itchy, blistering rash on elbows, knees, buttocks
• Brain fog, headaches, depression, anxiety — neurological manifestations
• Recurrent mouth ulcers
• Fertility issues — unexplained infertility, recurrent miscarriage
• Dental enamel defects — especially in children

“Sometimes the patient doesn’t realize that their symptoms are related to celiac disease. They say ‘I’m always tired.’ That fatigue can be connected to celiac disease. ‘I sleep badly’ — that too. Headaches, extraintestinal symptoms, even depression and anxiety can be related.”

— Taissa Castello, PodIgest Ep. 7

Getting diagnosed abroad

If you suspect celiac disease, the diagnostic process is the same worldwide:

1. Blood tests: Anti-tissue transglutaminase (anti-tTG IgA) is the primary screening test. Anti-endomysial antibodies (EMA) and total IgA should also be checked. Important: you must be eating gluten regularly for at least 6-8 weeks before testing — if you’ve already gone gluten-free, the results may be falsely negative (ACG Guidelines, 2023).
2. Upper endoscopy with biopsy: If blood tests are positive, an endoscopy with duodenal biopsies confirms the diagnosis by showing villous atrophy (Marsh classification).
3. Genetic testing (optional): HLA-DQ2 and HLA-DQ8 testing can rule out celiac disease (if negative, celiac is extremely unlikely) but cannot confirm it (many carriers never develop the condition).

Tip for expats: If you were diagnosed in Brazil, bring your medical records (translated if needed) when registering with a new healthcare provider. Terms to know: “doença celíaca” = “celiac disease” (US) / “coeliac disease” (UK/AU); “dieta sem glúten” = “gluten-free diet”; “biópsia duodenal” = “duodenal biopsy.”

The gluten-free diet: what you need to know

The only proven treatment for celiac disease is a strict, lifelong gluten-free diet. This means complete elimination of wheat, rye, barley, and their derivatives. Even small amounts of gluten (as little as 10-50mg per day — roughly a breadcrumb) can cause intestinal damage, even if you don’t feel symptoms (Catassi et al., 2007).

Safe Brazilian foods you can find abroad

• Tapioca flour / polvilho: Available at Brazilian stores worldwide and increasingly in regular supermarkets. Perfect for pão de queijo, tapioca crepes, and baking
• Rice and beans: Naturally gluten-free. A complete protein combination
• Cassava / mandioca: Available frozen at Latin American stores
• Corn-based products: Fubá (cornmeal), cuscuz de milho, pamonha — all safe
• Farofa: Made from cassava flour — safe if no wheat-based additives

Reading labels in different countries

• US: Look for “gluten-free” label (FDA: <20ppm). Allergen labeling law requires wheat declaration but not barley/rye specifically
• EU: Regulation 1169/2011 requires gluten-containing cereals to be highlighted in bold in the ingredients list. “Gluten-free” = <20ppm
• UK: Same EU standard applies post-Brexit. Coeliac UK’s crossed grain symbol is widely trusted
• Australia/NZ: Strictest standard globally — “gluten-free” means no detectable gluten. Look for the Coeliac Australia endorsement
• Brazil: Lei 10.674/2003 — “CONTÉM GLÚTEN” or “NÃO CONTÉM GLÚTEN” on all packaged foods

Cross-contamination: the hidden risk

Cross-contamination is the biggest daily challenge for celiacs — at home and especially when eating out. Gluten can transfer through shared cooking surfaces, utensils, oil, toasters, and even cutting boards.

“It took me a long time to realize I couldn’t buy sliced cheese from a bakery because of cross-contamination. These are small things in our daily lives that we gradually notice and adjust. And that’s exactly the role of a nutritionist — to help in this process of change.”

— Taissa Castello, PodIgest Ep. 7

Tips for eating out abroad:

• Use apps like Find Me Gluten Free to locate restaurants with GF options
• Learn to say “I have celiac disease, not an allergy or preference” in the local language — this communicates the seriousness
• Ask about shared fryers, shared pasta water, and flour-dusted surfaces
• Carry a restaurant card in the local language explaining your condition
• When in doubt, stick to naturally GF cuisines: Japanese (sashimi, rice), Mexican (corn tortillas), Thai (rice noodle dishes — check soy sauce)

Healing timeline: what to expect

After starting a strict gluten-free diet, intestinal healing takes time:

• 2-4 weeks: Many people notice symptom improvement (less bloating, more energy)
• 3-6 months: Blood antibodies (anti-tTG) begin to normalize
• 6-24 months: Intestinal villi gradually regenerate. Full mucosal healing may take up to 2 years in adults (Rubio-Tapia et al., 2023)
• Important: During healing, you may have temporary lactose intolerance (damaged villi produce less lactase). This usually resolves as the intestine heals

Nutritional deficiencies to monitor

Even after diagnosis and dietary adherence, celiacs should regularly monitor:

• Iron (ferritin, serum iron, TIBC) — most common deficiency
• Vitamin D — critical for bone health; malabsorption is common
• Vitamin B12 and folate
• Calcium — for osteoporosis prevention
• Zinc — affects immune function and wound healing
• Fiber intake — many GF products are low in fiber compared to their wheat-based counterparts

“Celiac disease is like sandpaper on the intestine. The villi become tiny and can’t absorb nutrients properly. So there are nutritional deficiencies that frequently occur — iron, vitamin D. If the person is at the peak of inflammation, having just been diagnosed, they’re even more likely to have these deficiencies.”

— Taissa Castello, PodIgest Ep. 3

When to seek specialized nutritional support

A nutritionist specialized in celiac disease can help you:

• Build a balanced GF diet adapted to your new country’s available foods
• Identify hidden sources of gluten in your current diet
• Address persistent symptoms despite a GF diet (may indicate cross-contamination, SIBO, or other conditions)
• Monitor and correct nutritional deficiencies
• Navigate the emotional aspects of diagnosis (food anxiety, social isolation)

If you’re a Brazilian living abroad and need nutritional guidance in Portuguese, I offer teleconsultations for patients worldwide. Having been through this journey myself, I understand both the clinical and personal sides of living with celiac disease.

Frequently asked questions

Can celiac disease develop at any age?

Yes, celiac disease can be triggered at any point in life, not just childhood, which is one of the more surprising, underappreciated facts about the condition. While it’s often diagnosed in children, a growing share of diagnoses now happen in adults, including people in their 40s, 50s, and beyond who ate gluten without issue for decades. This happens because celiac disease requires both a genetic predisposition (specifically the HLA-DQ2 or HLA-DQ8 genes) and an environmental trigger that activates the autoimmune response — and that trigger can occur later in life. Commonly reported triggers around symptom onset include significant stress, pregnancy, childbirth, viral or bacterial infections, or surgery. Having eaten gluten safely for years doesn’t rule out developing celiac disease later, and new-onset digestive symptoms, fatigue, or nutrient deficiencies in adulthood shouldn’t be dismissed just because there’s no childhood history. If celiac disease runs in your family or you notice new symptoms, proper antibody testing with your doctor is the appropriate way to investigate, regardless of age.

Is there a cure for celiac disease?

Not yet — the only current, medically validated treatment for celiac disease is a strict, lifelong gluten-free diet, and no medication or therapy has been approved to replace it. Research into alternative treatments is genuinely active, though: scientists are investigating enzyme supplements that could help break down small amounts of accidentally ingested gluten, vaccines aimed at retraining immune tolerance, and immunomodulatory therapies that target the autoimmune response directly. Several of these are in various stages of clinical trials, but none have reached approval for routine clinical use as of 2025. The encouraging news is that a strict gluten-free diet, properly followed, is highly effective: most people with celiac disease achieve full remission, meaning normalized antibody levels and healed intestinal mucosa on follow-up biopsy, typically within one to two years of consistent adherence. Remission is not the same as a cure — reintroducing gluten would reactivate the response — but it means the disease can be fully controlled with proper dietary management and support from a specialized nutritionist.

I’ve been gluten-free for months but still have symptoms. What now?

This is a common and frustrating experience, and it doesn’t necessarily mean something is seriously wrong — but it does deserve proper investigation rather than just waiting it out. Persistent symptoms after adopting a gluten-free diet have several well-documented explanations. The most frequent is unintentional cross-contamination, since gluten can hide in shared cooking surfaces, sauces, processed foods, and even some medications or supplements. Beyond that, secondary lactose intolerance is common early on, as the damaged gut lining temporarily loses its ability to produce lactase. Small intestinal bacterial overgrowth, or SIBO, can also develop or persist independently and mimic ongoing gluten exposure. Some patients have an overlapping irritable bowel syndrome that doesn’t resolve with diet alone, and in rare cases, refractory celiac disease — where the intestine doesn’t heal despite a strict diet — is the underlying issue. A specialized nutritionist can help systematically work through these possibilities using dietary review, targeted elimination, and appropriate testing referrals, rather than assuming the gluten-free diet simply isn’t “strict enough.”

Should my family members get tested?

Yes, and this is an important step that’s often overlooked. First-degree relatives of someone with celiac disease — parents, siblings, and children — carry a substantially elevated risk of having the condition themselves, estimated at 10 to 15%, compared with roughly 1 to 2% in the general population, reflecting the strong genetic component of the disease. What makes this particularly important is that celiac disease can be entirely silent, meaning a relative could test positive for the underlying autoimmune process and intestinal damage without any noticeable digestive symptoms, while still facing long-term health risks if left untreated. Because of this, current clinical guidelines recommend screening first-degree relatives with an anti-tTG IgA blood test regardless of whether they have symptoms (ACG Guidelines, 2023). This is a simple blood draw that can be arranged through a primary care doctor or gastroenterologist. If celiac disease runs in your family, encouraging relatives to get screened — even those who feel completely fine — is a worthwhile conversation to have.

References

1. Rubio-Tapia A, Hill ID, Semrad C, et al. ACG Clinical Guideline: Diagnosis and Management of Celiac Disease. Am J Gastroenterol. 2023;118(1):59-76.
2. Al-Toma A, Volta U, Auricchio R, et al. European Society for the Study of Coeliac Disease (ESsCD) guideline for coeliac disease and other gluten-related disorders. United European Gastroenterol J. 2019;7(5):583-613.
3. Caio G, Volta U, Sapone A, et al. Celiac disease: a comprehensive current review. BMC Med. 2019;17(1):142.
4. Catassi C, Fabiani E, Iacono G, et al. A prospective, double-blind, placebo-controlled trial to establish a safe gluten threshold for patients with celiac disease. Am J Clin Nutr. 2007;85(1):160-166.
5. Fasano A, Catassi C. Celiac Disease. N Engl J Med. 2012;367(25):2419-2426.

Read also (em português):

• Doença Celíaca: Guia Completo
• Sintomas da Doença Celíaca
• Celíaco: O Que Pode Comer
• Contaminação Cruzada por Glúten
• Book a Consultation

Disclaimer: This article is for informational and educational purposes only. It does not replace consultation, diagnosis, or treatment by a qualified healthcare professional. Each person has individual needs that should be evaluated in a clinical setting. Do not start, change, or stop any treatment without medical or nutritional guidance. Read our full disclaimer.

Read also: Celiac Disease Symptoms: The Complete Guide | Celiac Disease Diagnosis: Tests and Timeline | Gluten Cross-Contamination: Complete Guide | Living with Celiac Disease: Practical Guide

Taissa Castello Fonseca

Nutricionista Clínica • CRN-4 25106120

Especializada em doença celíaca, SIBO, doenças autoimunes e saúde da mulher. Celíaca há 9 anos. Atende 100% online para todo o Brasil.

Sobre a Taissa Agendar consulta @taissacastello.nutri