Bariatric Surgery Pre-Op Diet Guide

The purpose of this nutrition guide is to help shrink your liver prior to surgery by depleting stored glycogen. The goal is to consume 3 Whole meals per day. Breakfast, Lunch, and Dinner. Your meals should consist of the 3 Macronutrients – Protein, Healthy Fats and Fibrous Carbs.

Pre-Op Diet Guidelines Based on BMI

Start the pre-op diet based on you’re current BMI. (*BMI is in BOLD)

  • 30-32 =  2 days clear liquids only

  • 33-39 = 1 week pre-op diet including two days of clear liquids

  • 40-45 = 2 weeks pre-op diet including two days of clear liquids

  • 46-49 = 3 weeks pre-op diet including two days of clear liquids

  • 50-59 = 6 weeks of pre-op diet including two days of clear liquid diet

  • 60 plus = 8 weeks pre-op diet including two days of clear liquid

Bariatric Surgery Pre-Op Diet - The Liquid Diet

The Pre-Op Diet (Length of Time Depends on BMI)

  1. 2 – 3 protein shakes per day
  2. You can eat as many raw or cooked non-starchy vegetables as you want (no potato, corn, or peas)
  3. Two 4 -7oz servings of lean protein (chicken, turkey, fish, lean ground beef)
  4. 1 – 2 servings of healthy fat (salad dressing, olive oil, nuts, avocado, olives)
  5. You can add ½ cup of frozen berries or ½ banana to your protein shake
  6. You can make your shake with unsweetened vanilla almond milk or unsweetened coconut milk (NO regular milk: too much sugar)
  7. NO bread, rice, pasta, refined grains, sauces with sugar and no dairy (milk, yogurt, cheese)
Pre-Op Diet - 14 Days Prior to Bariatric Surgery

14 Days Prior to Surgery

  • Stop ALL vitamins and herbal supplements 2 weeks prior to surgery (based on your surgery date). With the exception of your prescribed medication. This will need to be discontinued day of surgery unless otherwise approved by your surgeon.
Pre-Op Diet - 7 Days Prior to Bariatric Surgery

7 Days Prior to Surgery

  • Some medications may need to be discontinued before surgery depending on the instructions of your SURGEON.
  • Specific medications to STOP: Coumadin, ANY ANTICOAGULANTS, OR BLOOD THINNERS Plavix, Aspirin, Ibuprofen, Motrin, Advil, Nuprin, Aleve or any other nonsteroidal anti-inflammatory medication.
    • ** Remember this also includes baby aspirin and most arthritis medications. As these can cause stomach irritation and possible more  bleeding postoperatively.
  • If there are any medications you need to stay on, talk directly with your nutritionist to get okay from your surgeon.
  • Discontinue birth control and supplemental hormones (IUD’S & IMPLANTS ARE TOTALLY SAFE and do not need to be removed).
Pre-Op Diet - 2 Days Prior to Bariatric Surgery

2 Days Prior to Surgery-Begin Clear Liquid Diet

  • Consume only clear liquids:
  • Apple or other clear juice without pulp or carbonation. (Honest Kids Juice is the lowest in sugar (10 g. per serving. If you get regular juice use 100% real juice and dilute 60/40 with water)
  • Clear broths: Chicken, Vegetable, or Beef.
  • Water or Flavored Water.
  • Sugar-free drinks such as crystal light, vitamin zero water, Powerade zero.
Pre-Op Diet - 8 Hours Prior to Bariatric Surgery

8 Hours Prior to Surgery

  • Absolutely nothing to drink after the midnight preceding surgery or 8 hours prior to your surgery.
  • Absolutely NO medications unless directed by the doctor. (If you have been pre-approved to take any medications by your physician leading up to surgery, you may take small sips of water for swallowing.)
  • Please bring ALL your prescribed medications (whether you are currently taking them or not) in properly labeled pharmaceutical bottles for documentation during Pre-Op testing. Do NOT take any medications after surgery until you have consulted with the doctor(s) and gotten approval.

During Your Pre-Op Diet

  • Discontinue ALL consumption of Dairy, Starches, Sugars, Desserts, and Fruit (with the exception of 1/2 cup berries or 1/2 a banana daily).
  • Discontinue drinking ALL caffeine 2 weeks prior to your surgery date. Caffeine is a diuretic, may cause dehydration and is acidic. You may drink decaffeinated coffee. Please ensure to stay hydrated.
  • Discontinue ALL carbonated beverages (sparkling water is okay).
  • Avoid: Ginseng, Ginger, Garlic and Omega 3 supplements. These increase bleeding risk. You may consume small quantities of garlic and ginger in cooking.
  • Begin the practice of NOT drinking 30 minutes prior to/during/post meals. This should become a LIFELONG HABIT.

Pre-Op Diet Guidelines

The purpose of this nutrition guide is to help shrink your liver prior to surgery by depleting stored glycogen. The goal is to consume 3 Whole meals per day. Breakfast, Lunch, and Dinner. Your meals should consist of the 3 Macronutrients – Protein, Healthy Fats and Fibrous Carbs.

Here is an ‘example’ of what your day could look like:

Approved Protein List

Grass-Fed Meat

  • Lamb
  • Lean/Extra-lean cuts of beef
  • Lean pork (Pork Tenderloin, Canadian Bacon)
  • Wild Game (Buffalo, Elk, Venison)

Organic Poultry

  • Chicken Breast
  • Eggs / Egg Whites
  • Egg Substitute
  • Turkey

Wild-Caught Fish

  • Cod
  • Flounder
  • Haddock
  • Halibut
  • Mackerel
  • Salmon
  • Sardines
  • Tuna
  • Seabass

Wild Caught Seafood

  • Clams
  • Crab
  • Lobster
  • Shrimp
  • Scallops
  • Squid

Protein Alternatives

  • Vegan Protein Powder
  • Whey Protein Powder
  • Nuts & Seeds
  • Beans (all varieties)
  • Impossible Burger
  • Tofu
  • Tempeh
  • Quorn
  • Fairlife Milk (Lactose-Free)

Approved Fats List

Healthy Fats 

  • Avocado
  • Olive Oil
  • Coconut Oil
  • Nuts (Limit to a handful per serving)
  • Nut Butters (1 TBSP per serving)
  • Chia Seeds
  • Flax Seeds
  • 85% Beef
  • 90% Bison
  • Salmon
  • Hemp Seeds
  • Whole Eggs

Approved Fibrous Carbs List

You may eat an unlimited amount of Fibrous Carbs (VEGETABLES) You are not limited to the list.

  • Celery
  • Bok Choy
  • Mushrooms
  • Zucchini
  • Radish
  • Asparagus
  • Tomato
  • Cauliflower
  • Bell Pepper
  • Cabbage
  • Eggplant
  • Brussel Sprouts
  • Broccoli
  • Green Beans
  • Carrots
  • Spaghetti
  • Squash
  • Pumpkin
  • Peas
  • Corn
  • Delicata Squash
  • Black Beans
  • Lentils
  • Chickpeas
  • Acorn Squash
  • Butternut Squash

Please cut out the following from your diet

  • Rice
  • Pasta
  • Potatoes/Sweet Potatoes
  • Quinoa/Buckwheat
  • Muffins/Bread/Rolls (ALL WHEAT & GLUTEN)
  • Oats/Cereals/Granola All Dairy
  • Anything Processed

Have as much soup as you would like.

Weight loss soup recipe:

Recommended Protein Powders

Ideally, you want to get your protein intake from real foods. However, if you need to supplement with protein powder, we recommend sticking with plant-based proteins. Whey isolate is okay and you also may have premier protein shakes. Choose a protein shake that is high in protein 20 grams or more and low in sugar <5 grams.

Here are a few of our favorites. You can find them on Amazon.

  • Vega One Organic All-in-One Shake
  • Vega Sport Performance
  • Nuzest Clean Lean Protein – Premium Vegan Protein Powder
  • Naked Pea Protein

2 Days Pre-Surgery Prep

2 Days Pre Surgery, you need to only consume Clear Liquids.

These are the approved Clear Liquids you may have:

  • Non-Carbonated Sugar-Free Clear Liquids
  • Water
  • Bone Broths: Chicken, Vegetable, Beef
  • Crystal Light / Vitamin Zero Water / Powerade Zero / Propel
  • Caffeine Free Herbal Tea
  • Caffeine Free Coffee
  • Sugar-Free Jello
  • Sugar-Free Popsicles
  • You may eat 2 Plain Fat-Free Greek Yogurts or Organic Plain Fat-Free Yogurt per day during the Clear Liquid phase.

Please DO NOT drink this:

  • Premier Protein Water Protein Shakes