Bariatric Post‑Op Dietary Guidelines
Your surgery is a powerful tool—daily choices make it shine. Use these guidelines for the first 30 days and beyond to protect healing, nourish your body, and build habits that last.

Phases at a Glance
Quick reference—tap a card's anchor below to jump to full details.
Daily Lifestyle Tips
Simple actions that compound into success.
- ✔ Track daily protein, fiber, and calories.
- ✔ Stay hydrated.
- ✔ Measure portions (especially slider foods).
- ✔ Move at least 3×/day.
- ✔ Take your supplements.

Pre‑Surgery Practice & Checklist
- ✔ Plan a schedule for meals, fluids, vitamins, and minerals.
- ✔ Start brisk walks and light resistance bands.
- ✔ Limit alcohol; none on liver‑shrink diet.
- ✔ Choose low‑fat foods; avoid fried foods and sugary snacks.
- ✔ Drink ≥64 oz/day of low or no‑cal beverages; stop sugary drinks.
- ✔ Eat 3 meals/day; don’t skip breakfast; add whole fruits/veg.
- ✔ Find a protein supplement that meets the program criteria.
- ✔ Chew 20–40× per bite to paste; sip liquids between—not with—meals; practice no straw.
- ✔ Purchase chewable vitamin/mineral supplements.
- ✔ Prefer natural sweeteners (stevia/monk fruit); reduce fast food; downsize to <6 in plates.
- ✔ Wean off caffeine/carbonation for first 30 days post‑op.
- ✔ Keep this handout handy; keep tracking with an app.
- ✔ Pill crusher/splitter (confirm with your MD).
- ✔ Bariatric utensil set + small plate; <6 in appetizer plates for meals.
- ✔ Measuring cups/spoons.
- ✔ Prep & freeze small portions of purees (use ice‑cube trays).
- ✔ Mini food processor or blender.
- ✔ Buy vitamins/minerals/protein—sample first; don’t stock up.
- ✔ Pill cases to help remember doses.
Dietary Information & Phases
Advance one step at a time. Portions start tiny and grow slowly as healing progresses.

Days 0–2 Phase 1 — Clear Liquids
Hydration first. 1–2 oz per meal (shot‑glass size). Use a protein supplement to reach ~30 g/day.
Examples
- ✔ Broth
- ✔ Powerade Zero
- ✔ Sugar‑free gelatin & popsicles
- ✔ Herbal, caffeine‑free tea
- ✔ Boost Breeze Clear / Premier Protein Clear / Isopure Clear
One protein drink can cover 4–8 mini‑meals; refrigerate and discard leftovers.

Days 3–14 Phase 2 — Full Liquids
Still 1–2 oz/meal; target ≥30 g protein/day from shakes. Liquids = consistency of milk.
- ✔ Skim/Lactaid/soy/almond milk
- ✔ Strained smooth cream soups (no pieces)
- ✔ No‑added‑sugar instant breakfast (with non‑fat milk)
- ✔ Pourable light yogurt (no fruit pieces)
- ✔ Thinned sugar‑free, fat‑free pudding/custard
- ✔ Thinned cream of wheat/rice (+ protein powder)
- ✔ Thinned smoothies/milkshakes (no chunks)
Avoid citrus/tomato 3 weeks; avoid (de)caf coffee 6 weeks.

Days 15–21 Phase 3 — Pureed
2–4 Tbsp/meal. Applesauce/baby‑food texture. Dry meals—no liquids with meals.
- ✔ Protein first; then produce.
- ✔ Start small; if not tolerated, step back to liquids and retry.
- ✔ If you can chew it, don’t do it—puree it; strain seeds/skins/lumps.
- ✔ Add liquid to blend (milk/broth/yogurt/etc.).

Days 22–28 Phase 4 — Soft Solids
2–4 Tbsp/meal; introduce 1 new food per meal; space meals 4–5 hours.
- ✔ Moist baked fish or rotisserie chicken
- ✔ Scrambled/poached eggs
- ✔ Soft cheeses (feta, ricotta, cottage, cream)
- ✔ Canned peaches/pears (in water/juice)
- ✔ Banana, shaved deli meats, imitation crab/baby shrimp
- ✔ Well‑cooked veg (no skins/seeds; avoid corn/peas)

Day 29+ Phase 5 — Regular Diet
Go slow; small bites; test tolerance. Rice/pasta/doughy bread may need 2–3 more months.
- 1) Try one small bite; chew well; pause and assess.
- 2) If too full/nauseated/vomiting: stop → clear liquids → pureed next meal → retry solids later.
Common Problem Foods (first 2–3 months)
- ✔ Chips & hard taco shells
- ✔ Nuts/seeds unless chewed to paste
- ✔ Breads/rolls/biscuits (toast may be easier)
- ✔ Pasta and rice
- ✔ Citrus membranes; dried fruit; popcorn; coconut
- ✔ Fried/greasy foods
- ✔ Early post‑op: red meats incl. hamburger/hot dogs (1 month); steaks/roasts/pork/wild game often poorly tolerated
Important Eating Patterns & Habits
- ✔ 3 meals/day; avoid grazing.
- ✔ Measure meals ≤ 1/2 cup long‑term (first month 2–4 Tbsp).
- ✔ Protein first.
- ✔ No liquids 30 min before → during → 30 min after meals.
- ✔ Daily vitamins/minerals for life.
- ✔ Meals last 20–30 min; chew to paste; use small utensils; mindful eating.
- ✔ 64+ oz/day zero‑cal, non‑carbonated, caffeine‑free fluids between meals.
- ✔ Sliders (yogurt, soups, oatmeal, cottage cheese, puddings) = measure 1/2 cup max.
Protein Guide
Target 60–80 g/day from shakes + food
Choosing a supplement
- ✔ Whey or plant‑based; pea if whey intolerant.
- ✔ Powder or ready‑to‑drink.
- ✔ ≥20–30 g protein/serving; total carbs < 1/2 the grams of protein.
Protein in common foods
Make shakes interesting
- ✔ Add extracts/spices (vanilla, almond, cinnamon).
- ✔ Use cocoa powder; add water/milk if too sweet/thick.
- ✔ Blend with ice for a slushy; freeze into pops.
- ✔ Mix into yogurt/Greek yogurt or sugar‑free gelatin.
Daily Vitamins & Minerals
- ✔ Chewable/liquid/crushed for 6 weeks (per provider).
- ✔ Calcium citrate 1500–2000 mg/day in 3 × 500–600 mg doses with Vit D.
- ✔ Bariatric multivitamin (150–200% RDA); consider without iron if constipated.
- ✔ Vitamin D3 2000 IU/day (separate if not in calcium).
- ✔ Vitamin B12 350–500 mcg PO daily or 1000 mcg IM/SQ/day.
- ✔ Iron: 18 mg/day males; 45–60 mg/day menstruating women.
Fluids
- ✔ No liquids 30 min before meals, none with meals, none for 30 min after.
- ✔ Sip steadily between meals; avoid gulping/straws 4–6 weeks.
- ✔ Goal ≥64 oz/day (≥½ plain water).
- ✔ Zero‑cal flavored beverages okay; avoid sugared drinks.
- ✔ Avoid caffeine first 30 days; carbonation 4–12 weeks; alcohol 3–6 months.
Caffeine Guidance
- ✔ After 30 days, keep total ≤300–400 mg/day; ≤100 mg at once.
- ✔ Not after 5 PM or within 3 hrs of bedtime.
- ✔ Protein needs first—protein + coffee shakes after 30 days.
Sugar & Fat
- ✔ Avoid high‑sugar foods and calorie‑dense soft foods/liquids (ice cream, shakes, candy, sweet drinks).
- ✔ Limit fried foods and added fats; choose healthy fats in moderation (olive/canola/avocado/nut butters/olives).
Possible Complications & What Helps
Nausea / Vomiting
- Often from large bites, fast eating, poor chewing, too much volume, or liquids with meals.
- Eat slowly; stop at first fullness; avoid lying down after meals.
- Call your doctor if frequent or persistent.
Hair Loss (Telogen Effluvium)
- Ensure 60–80 g protein/day; consider zinc ≤50 mg/day if needed.
- Evaluate iron deficiency if persistent; regrowth often follows after several months.
Constipation
- Prevent with ≥64 oz fluid, frequent walking, gradual fiber when on regular foods (chew well).
- Consider baby food prunes/unsweetened prune juice/oatmeal; inulin‑based soluble fiber if needed.
- If persistent, call our office before using laxatives.
Questions? We’re here for you
Nurse line: 208‑782‑3993
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