# Gluten-Free Diet Guide **Prepared by:** Pedro Cheung MD **Last Updated:** May 2026 ## For Patients with Gluten Intolerance (Non-Celiac Gluten Sensitivity) and Celiac Disease --- > **Important:** If you suspect you have celiac disease or gluten intolerance but have not yet been tested, **do not start a gluten-free diet before getting tested.** Removing gluten from your diet before testing can cause test results to be inaccurate. Talk to your doctor first. --- ## What Is Gluten? Gluten is a protein found in three grains: - **Wheat** (including all its forms: durum, spelt, semolina, couscous, bulgur, farro, emmer, farina, einkorn, kamut) - **Barley** - **Rye** Gluten is also found in **triticale** (a hybrid of wheat and rye), **malt** (made from barley), **malt vinegar**, and **brewer's yeast** (usually derived from beer brewed with wheat or barley). --- ## Why Go Gluten-Free? ### Celiac Disease Celiac disease is a serious autoimmune condition. When a person with celiac disease eats gluten, the immune system mistakenly attacks the lining of the small intestine. Over time, this causes: - Damage to the intestinal villi (the tiny finger-like structures that absorb nutrients) - Poor absorption of vitamins and minerals - Digestive symptoms such as bloating, diarrhea, and abdominal pain - Fatigue, headaches, joint pain, and depression - Long-term complications including anemia, osteoporosis, and neurological issues **Even tiny amounts of gluten can cause intestinal damage in people with celiac disease — even if you feel no symptoms.** A strict, lifelong gluten-free diet is the only proven treatment. ### Non-Celiac Gluten Sensitivity (Gluten Intolerance) People with non-celiac gluten sensitivity (NCGS) experience real symptoms when they eat gluten — including bloating, abdominal pain, fatigue, and brain fog — but do not have the autoimmune intestinal damage seen in celiac disease. Gluten still needs to be avoided, though the level of strictness may be slightly more flexible. Your doctor or dietitian will guide you based on your individual situation. --- ## Foods That ALWAYS Contain Gluten — AVOID These These are the most common gluten-containing foods in the American diet. **Do not eat these unless they are specifically labeled "gluten-free."** ### Breads, Baked Goods & Grains - Bread, rolls, buns, bagels, English muffins, pita bread - Tortillas (flour-based), wraps, flatbreads - Pasta (all regular pasta, noodles, couscous) - Pizza dough and pizza crust - Crackers, pretzels, breadsticks - Muffins, scones, biscuits, croissants - Pancakes, waffles, French toast (made with regular flour) - Cereals (most — including many granolas and oatmeal, unless certified gluten-free) - Cookies, cakes, pastries, pies, donuts ### Grains to Avoid - Wheat flour, whole wheat flour, white flour, enriched flour - Semolina, durum, spelt, farro, kamut, einkorn, emmer - Bulgur, couscous, farina - Barley, barley malt, barley flour - Rye, rye bread, rye flour - Triticale ### Other Common Sources - **Beer** (made from barley or wheat; look for gluten-free beer) - Soy sauce (most brands contain wheat — use tamari or coconut aminos instead) - Regular soy sauce, teriyaki sauce, many stir-fry sauces - Most gravies and cream-based soups (thickened with wheat flour) - Breaded and battered foods (fried chicken, fish sticks, onion rings, chicken nuggets) - Malt vinegar (on fish and chips) - Many salad dressings and marinades - Imitation crab and some processed seafood - Some flavored chips, seasoned nuts, and snack mixes - Many processed deli meats and hot dogs - Some medications — check with your pharmacist --- ## Foods That Are NATURALLY Gluten-Free — Safe to Eat The good news: many whole, fresh foods are naturally free of gluten. Base your diet around these. ### Proteins - **Fresh meats:** beef, pork, lamb, bison, venison - **Poultry:** chicken, turkey, duck - **Seafood:** fish (salmon, tuna, halibut, cod, tilapia), shrimp, crab, lobster, oysters, clams, mussels, scallops - **Eggs** - **Legumes:** beans (black, pinto, kidney, chickpeas), lentils, edamame, tofu, tempeh (check label) ### Grains, Flours & Starches (Naturally Gluten-Free) - **Rice** (white, brown, wild, basmati, jasmine) - **Quinoa** _(a California favorite — packed with protein and fiber)_ - **Corn** / maize / polenta / grits - **Oats** — _only if labeled "certified gluten-free"_ (regular oats are often cross-contaminated) - **Amaranth, teff, millet, sorghum, buckwheat** - **Potatoes** (white, red, Yukon gold, purple, sweet potato) - **Tapioca, arrowroot, cassava (yuca)** - **Flours made from:** rice, corn, potato, almond, coconut, chickpea, buckwheat, cassava, oat (certified GF) ### Fruits & Vegetables All fresh and frozen fruits and vegetables are naturally gluten-free. California's local favorites include: - **Avocados** — a superstar of the gluten-free diet; rich in folate, fiber, and healthy fats (nutrients often lacking in a GF diet) - Citrus fruits (oranges, lemons, limes, grapefruits) - Strawberries, blueberries, raspberries, blackberries - Stone fruits (peaches, plums, apricots, cherries, nectarines) - Artichokes, asparagus, broccoli, cauliflower - Leafy greens (spinach, kale, arugula, Swiss chard, collard greens) - Tomatoes, cucumbers, zucchini, bell peppers, eggplant - Beets, carrots, celery, garlic, onions, shallots - Corn on the cob, peas, green beans - Mushrooms (excellent source of niacin and B vitamins) > **Tip for Californians:** Shop at farmers markets for an abundance of naturally gluten-free seasonal produce. Most of what you find at a farmers market is inherently gluten-free. ### Dairy & Dairy Alternatives - Milk, cream, butter, ghee - Cheese (most natural cheeses: cheddar, mozzarella, brie, feta, parmesan, goat cheese — check processed cheese products) - Plain yogurt, Greek yogurt, kefir - Sour cream, crème fraîche - Gluten-free ice cream and gelato - **Dairy-free alternatives:** almond milk, oat milk _(must be certified GF)_, coconut milk, soy milk, rice milk — check labels ### Nuts, Seeds & Healthy Fats - All plain, unseasoned nuts: almonds, walnuts, cashews, pistachios, pecans, macadamias - All seeds: chia, flax, sunflower, pumpkin, sesame, hemp - Nut and seed butters (plain versions — check labels on flavored varieties) - Olive oil, avocado oil, coconut oil - **Avocados** (again — a must for California GF living!) ### Gluten-Free Condiments & Sauces (Safe Options) - Coconut aminos (soy sauce substitute) - Tamari (wheat-free soy sauce — check label for "gluten-free") - Fish sauce (most are GF — check label) - Salsa (most are GF — check label) - Guacamole (naturally GF) - Mustard (most plain mustards are GF — check labels) - Ketchup (most brands are GF) - Vinegars: apple cider vinegar, white wine vinegar, balsamic vinegar, rice vinegar _(but NOT malt vinegar)_ - Hummus (most are GF — check labels) - Tahini - Most hot sauces (check labels) - Pesto (most are GF — check) ### Beverages - Water, sparkling water, flavored water (check label) - Coffee, tea - 100% fruit juice - Most sodas and sports drinks (check labels) - **Wine** (all wine is naturally GF) - **Cider** (most hard cider is GF — check labels) - **Gluten-free beer** (look for certified GF brands at Whole Foods, Trader Joe's, Total Wine) - Most spirits (vodka, rum, tequila, gin — but see note on whiskey/scotch) > **Note on spirits:** Most distilled spirits are considered gluten-free even if made from gluten-containing grains, because the distillation process removes gluten proteins. However, if you are very sensitive, choose spirits made from naturally GF ingredients such as tequila (agave), rum (sugar cane), or potato vodka. --- ## Watch Out: Hidden Sources of Gluten Gluten hides in many unexpected places. Always read ingredient labels carefully. |Food Category|Hidden Gluten Risk|What to Look For| |---|---|---| |Soups & broths|Wheat used as thickener|"Modified food starch," "wheat starch," "roux," "hydrolyzed wheat protein"| |Sauces & gravies|Flour used as thickener|Soy sauce, teriyaki sauce, Worcestershire sauce (some brands)| |Salad dressings|Malt vinegar, wheat starch|"Malt vinegar," "wheat," "modified starch"| |Flavored chips & snacks|Wheat-based coatings|Seasoned chips, flavored popcorn, some trail mixes| |Spice mixes & seasoning packets|Fillers and anti-caking agents|"Wheat flour," "starch" without specifying type| |Deli meats & hot dogs|Wheat-based fillers|"Modified food starch," "wheat protein"| |Imitation crab (surimi)|Contains wheat starch|"Starch," "wheat" in ingredient list| |Candy|Malt flavoring, wheat flour|"Malt," "barley malt extract," "wheat starch"| |Oats (regular)|Cross-contamination|Must say "certified gluten-free"| |Soy sauce|Usually contains wheat|Use tamari or coconut aminos instead| |Communion wafers|Made from wheat|Ask church for gluten-free option| |Medications & supplements|Starch binders|Ask pharmacist to confirm GF| |Lipstick/lip balm|Some contain gluten|Check labels if you ingest any| --- ## Oats: A Special Note Oats are naturally gluten-free, but they are **almost always cross-contaminated** with wheat, barley, or rye during growing, harvesting, and processing. For this reason: - **People with celiac disease** should eat **only certified gluten-free oats**, and even then, introduce them slowly. Some people with celiac disease react to a protein in oats (avenin) and may need to avoid oats entirely. - **People with gluten intolerance** may tolerate certified GF oats better, but should still choose certified options. Look for oatmeal, granola, and oat flour labeled **"Certified Gluten-Free"** from brands like Bob's Red Mill GF, Purely Elizabeth, or GF Harvest. --- ## Cross-Contamination: A Critical Concern for Celiac Disease For people with celiac disease, cross-contamination (also called cross-contact) can cause real intestinal damage even when there are no symptoms. ### At Home - **Use separate cutting boards** — dedicate one only to gluten-free food preparation - **Replace wooden utensils, wooden cutting boards, and scratched non-stick pans** — gluten proteins can hide in scratches and pores - **Label your gluten-free foods** with colored stickers if you share a kitchen - **Store GF foods separately** — in a dedicated shelf or cabinet - **Clean surfaces thoroughly** before preparing GF food - **Use separate toasters** — a regular toaster will always contaminate GF bread - **Do not share condiment jars** (peanut butter, butter, jam) — crumbs from a knife can contaminate the jar. Use squeeze bottles or have dedicated GF jars. - Keep GF flours stored away from wheat flour — wheat flour particles are airborne and can settle on surfaces ### Dining Out Dining out is one of the biggest challenges for people with celiac disease. Studies have found that **about one-third of restaurant foods labeled "gluten-free" tested positive for gluten contamination**, with pizza and pasta carrying the highest risk. **Tips for safer restaurant dining:** 1. Call ahead during non-busy hours to ask about gluten-free preparation practices 2. Explain that you have a medical condition (not just a preference) — this alerts staff to take extra care 3. Ask whether gluten-free items are cooked in the same fryer oil as gluten-containing items (shared fryer oil is a source of cross-contamination) 4. Request that your food be prepared with clean utensils and on a clean surface 5. Avoid restaurants where flour is airborne (pizza places, fresh pasta restaurants, bakeries) 6. For sushi: ask for gluten-free soy sauce (tamari) and be aware that some imitation crab contains wheat 7. **Useful apps:** Find Me Gluten Free, Allergy Eats — to find vetted GF-friendly restaurants **California-Friendly GF Dining Tips:** - Most Mexican restaurants can accommodate GF with corn tortillas instead of flour — ask if they are cooked separately - Sushi and Japanese restaurants: bring your own tamari or ask for GF soy sauce - Farm-to-table and health-focused restaurants (common in the Bay Area, Los Angeles, San Diego) often have well-trained staff and dedicated GF options - Whole Foods Market, Erewhon, and many California grocery stores have excellent GF-labeled prepared food sections --- ## Gluten-Free at the Grocery Store ### Reading Labels By U.S. FDA law, any food labeled **"gluten-free"** must contain fewer than **20 parts per million (ppm)** of gluten — the level considered safe for most people with celiac disease. **Look for these label claims:** - "Certified Gluten-Free" (from organizations like GFCO — Gluten-Free Certification Organization — most stringent, requires <10 ppm) - "Gluten-Free" (FDA standard: <20 ppm) - "No Gluten Ingredients" (less reliable — does not guarantee against cross-contamination) **Red flag ingredients on labels:** - Wheat (and any form: durum, spelt, farro, semolina, einkorn, emmer, kamut, bulgur, farina) - Barley / barley malt / barley extract - Rye - Malt / malt flavoring / malt extract / malt vinegar - Brewer's yeast - Triticale - "Starch" or "modified food starch" (unless specified as corn starch, tapioca starch, potato starch, or arrowroot) - "Natural flavors" (occasionally wheat-derived — call manufacturer if concerned) - "Hydrolyzed protein" (check source) ### Where to Shop in California Most major California grocery chains carry excellent gluten-free selections: - **Whole Foods Market** — extensive certified GF section, knowledgeable staff - **Trader Joe's** — affordable GF options, clearly labeled - **Erewhon** (Los Angeles area) — premium GF and organic options - **Sprouts Farmers Market** — good GF selection throughout California - **Vons, Safeway, Ralphs, Albertsons** — dedicated GF aisles in most stores - **Costco** — bulk GF staples (rice, quinoa, almond flour, certified GF oats, GF pasta) - **Target** — growing GF selection, Good & Gather GF products - **Local co-ops and natural food stores** — excellent for certified GF bulk grains and flours --- ## Eating a Balanced Gluten-Free Diet: What the Research Says While going gluten-free is medically necessary for celiac disease and gluten intolerance, **"gluten-free" does not automatically mean "healthy."** Research consistently shows that people on a gluten-free diet are at risk for certain nutritional gaps: ### Common Nutritional Deficiencies on a GF Diet |Nutrient|Why It's Lacking|How to Get More| |---|---|---| |**Fiber**|GF products often use refined flours low in fiber|Eat more beans, lentils, quinoa, vegetables, fruits, chia/flax seeds, nuts| |**Iron**|GF products are rarely fortified; poor absorption in celiac|Lean red meat, chicken, fish, tofu, lentils, spinach, pumpkin seeds| |**Folate (B9)**|GF grains not enriched; common deficiency|Dark leafy greens, avocado, asparagus, beans, fortified GF cereals| |**Vitamin D**|Often deficient; few food sources|Salmon, sardines, canned tuna, egg yolks; sun exposure; supplements| |**Calcium**|Dairy avoidance + poor absorption|Dairy products, canned salmon/sardines with bones, leafy greens, fortified GF milks| |**Magnesium**|Absorbed in damaged intestine|Pumpkin seeds, dark chocolate, spinach, black beans, almonds| |**Zinc**|Lost through intestinal damage|Beef, shellfish (especially oysters), pumpkin seeds, hemp seeds, lentils| |**B Vitamins (B6, B12)**|GF products rarely fortified|Meat, fish, eggs, dairy, fortified GF cereals| |**Vitamin B6**|Can worsen on GF diet|Chicken, tuna, salmon, bananas, avocados, potatoes| > **Key takeaway:** Build your gluten-free diet around **whole, naturally GF foods** — especially vegetables, fruits, lean proteins, legumes, nuts, and seeds — rather than relying heavily on packaged GF products, which tend to be low in fiber and micronutrients and high in sugar, fat, and refined starch. ### The California Advantage Californians are well-positioned to eat a nutritious gluten-free diet because of: - Year-round access to a wide variety of fresh, locally grown produce - Abundant farmers markets - A food culture that already embraces quinoa, avocado, fresh fish, beans, and salads - Many health-conscious and allergy-aware restaurants - Easy access to natural and specialty food stores --- ## Sample Gluten-Free Meal Ideas (California Style) ### Breakfast - Certified GF oatmeal with fresh berries, chia seeds, and almond butter - Scrambled eggs with sautéed spinach, mushrooms, and avocado on a corn tortilla - Smoothie: frozen mango, spinach, banana, almond milk, flaxseed - Greek yogurt parfait with fresh California strawberries, certified GF granola, and honey - Rice cakes with almond butter and sliced banana ### Lunch - Grain bowl: quinoa + roasted butternut squash + kale + roasted chickpeas + tahini dressing - Taco bowl: seasoned ground beef or black beans + brown rice + guacamole + salsa + shredded cabbage (skip the tortilla or use corn) - Avocado and cucumber rice paper rolls with tamari dipping sauce - Big salad: arugula + grilled salmon + cherry tomatoes + cucumber + avocado + lemon-olive oil dressing - Lentil soup with gluten-free bread ### Dinner - Grilled wild-caught salmon with roasted asparagus and baked sweet potato - Chicken stir-fry with broccoli, bell peppers, snap peas, over jasmine rice — use tamari or coconut aminos instead of soy sauce - Grass-fed burger (no bun, or on a certified GF bun) with sweet potato fries - Shrimp tacos on corn tortillas with mango salsa, shredded purple cabbage, and lime crema - Cauliflower rice bowls with Korean-inspired ground turkey (no soy sauce — use tamari), kimchi (check label), sesame seeds - Bean and vegetable chili with a side of corn tortilla chips (certified GF brand) ### Snacks - Fresh avocado with sea salt + plain corn tortilla chips (certified GF) - Celery + almond butter - Apple slices + walnut butter - Hummus + sliced bell peppers, cucumbers, carrots - A small handful of mixed nuts (unseasoned) - Hard-boiled eggs - Dates stuffed with almond butter - Plantain chips (certified GF) - Fresh guacamole + sliced jicama --- ## Gluten-Free Grocery Staples List ### Pantry - Brown rice, white rice, wild rice - Quinoa - Certified GF rolled oats - GF pasta (brown rice pasta, chickpea pasta, lentil pasta) - Corn tortillas (check "made in dedicated GF facility") - Canned beans (black, pinto, kidney, chickpeas) — check labels - Canned tomatoes, tomato sauce, salsa - Tamari or coconut aminos - Chicken or vegetable broth (GF labeled) - Almond flour, coconut flour, tapioca flour, rice flour - Certified GF all-purpose flour blend (Bob's Red Mill 1-to-1, King Arthur GF, Cup4Cup) - Olive oil, avocado oil, coconut oil - Apple cider vinegar, balsamic vinegar - Nuts (almonds, walnuts, cashews, pistachios) - Nut butter (almond, cashew, peanut — plain) - Chia seeds, flaxseed, hemp seeds ### Refrigerator/Freezer - Fresh eggs - Fresh salmon, chicken, ground beef or turkey - Plain Greek yogurt - Block cheeses (cheddar, parmesan, mozzarella) - Almond or oat milk (certified GF) - Frozen edamame - Frozen wild blueberries - Frozen riced cauliflower and frozen vegetables (plain, no sauce) - Tofu (firm or extra-firm) --- ## Monitoring Your Health on a Gluten-Free Diet ### For Celiac Disease — Regular Follow-Up Is Essential Celiac disease requires ongoing medical monitoring, not just dietary change. Ask your doctor about: - **Repeat blood tests** (tTG-IgA, total IgA) — usually at 6 months, then annually — to confirm your intestine is healing - **Bone density (DEXA) scan** — celiac disease increases the risk of osteoporosis - **Nutritional blood tests** at diagnosis and during follow-up: - Iron / ferritin (iron stores) - Vitamin D (25-OH vitamin D) - B12 and folate - Zinc and magnesium - Complete blood count (for anemia) - **Referral to a registered dietitian** who specializes in celiac disease — at minimum at diagnosis, and ideally annually - **Consider a gluten-free support group** — the Celiac Disease Foundation, Beyond Celiac, and the Gluten Intolerance Group (GIG) all have resources and community support ### For Gluten Intolerance (NCGS) - Follow up with your doctor if symptoms persist or worsen on a GF diet - Consider a trial elimination diet guided by a dietitian - Even without celiac disease, nutritional deficiencies can develop on a poorly planned GF diet — request nutritional labs if you have symptoms of fatigue, weakness, or poor wound healing --- ## Frequently Asked Questions **Q: Is gluten-free food healthier for everyone?** No. Unless you have celiac disease, gluten intolerance, or another medically indicated reason, a gluten-free diet offers no proven health benefit and can actually result in nutritional deficiencies if not well planned. Do not start a GF diet without guidance from your doctor. **Q: Can I eat oats?** Only certified gluten-free oats. Regular oats are almost always cross-contaminated. Even with certified GF oats, people with celiac disease should introduce them slowly, as a small percentage react to a protein in oats (avenin). Discuss with your doctor or dietitian first. **Q: What about wheat starch labeled "gluten-free"?** Some European GF products use specially processed wheat starch that is treated to reduce gluten below 20 ppm. These are considered safe for most people with celiac disease under FDA and Codex Alimentarius standards, but some individuals are more sensitive. Speak with your gastroenterologist. **Q: Is sourdough safe?** Regular sourdough is NOT gluten-free. Some traditional sourdough fermentation methods reduce gluten content, but levels are unpredictable and not safe for celiac disease. Only eat sourdough that is made from certified GF flour and labeled gluten-free. **Q: Can I drink alcohol?** Wine and most hard ciders are naturally GF. Most distilled spirits are considered safe. Beer made from wheat or barley must be avoided — choose certified GF beer (available at Whole Foods, BevMo, and most California stores). Malt beverages such as hard seltzers made from malted barley should be avoided — check labels. **Q: What about medications?** Some medications use wheat starch as a binder. Always inform your pharmacist and doctor about your celiac disease or gluten intolerance so they can verify that all prescriptions and over-the-counter medications are gluten-free. **Q: If I feel fine, do I still need to stay strictly gluten-free?** Yes — if you have celiac disease. Intestinal damage can occur without noticeable symptoms. "Silent celiac disease" can still lead to anemia, osteoporosis, and increased cancer risk over time. Strict adherence is important even when you feel well. --- ## Key Resources - **Celiac Disease Foundation:** [celiac.org](https://celiac.org/) - **Beyond Celiac:** [beyondceliac.org](https://beyondceliac.org/) - **Gluten Intolerance Group (GIG):** [gluten.org](https://gluten.org/) - **National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK):** [niddk.nih.gov](https://www.niddk.nih.gov/health-information/digestive-diseases/celiac-disease) - **Find Me Gluten Free App** — crowd-sourced restaurant reviews from the GF community - **Allergy Eats App** — restaurant finder for food allergies and intolerances - **GFCO (Gluten-Free Certification Organization):** [gfco.org](https://gfco.org/) — find certified products --- ## Summary: Your Gluten-Free Plate at a Glance |Build Your Plate With|Limit or Avoid| |---|---| |Fresh vegetables and fruits|Wheat bread, pasta, pizza, crackers| |Lean proteins: fish, chicken, eggs, beans|Regular beer and malt beverages| |Naturally GF grains: rice, quinoa, potatoes|Soy sauce (use tamari instead)| |Healthy fats: avocado, olive oil, nuts|Packaged GF products as dietary staples| |Certified GF whole grains: oats, sorghum, teff|Breaded/battered foods| |Dairy or fortified dairy-free alternatives|Deli meats with fillers| --- _This handout is for educational purposes and does not replace individualized medical advice. Please work with your physician and a registered dietitian who specializes in celiac disease to develop a safe and nutritionally complete gluten-free diet tailored to your needs._