Duodenal Switch Surgery Pre-Operative Diet Guide

The purpose of this nutrition guide is to help shrink your liver prior to the DS surgery by depleting stored glycogen. The goal is to consume 2-3 meals of solid, macronutrient-rich foods per day. These whole meals will stay in your stomach longer keeping you full, while providing your body with vital nutrients. In addition, utilize protein shakes as a snack, generally, 1-2 protein shakes per day. This will ensure you meet protein goals, which will promote wound healing during your post-op recovery. 

Pre-Op Diet Guidelines Based on BMI

Start the pre-op diet based on your current BMI.

  • 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 Guidelines Based on BMI

General Overview

  • 1 – 2 protein shakes per day -You may purchase these in any health food store or many grocery stores. Please be sure it contains at least 20 grams of protein per serving.  Sugar should be 5 grams or less.

  • You can eat as many raw or cooked non-starchy vegetables as you want (no potato, corn, or peas)

  • Two 4 – 7 ounce servings of lean protein (chicken, turkey, fish, lean ground beef)

  • 1 – 2 servings of healthy fat (salad dressing, olive oil, nuts, avocado, olives)

  • You can add ½ cup of frozen berries or ½ banana to your protein shake

  • You can make your shake with unsweetened vanilla almond milk or unsweetened coconut milk (NO regular milk: too much sugar)

  • NO bread, rice, pasta, refined grains, tortillas, sauces with sugar, and no dairy (milk, yogurt, cheese)

  • NO alcohol, marijuana, or THC products two weeks prior to surgery. These increase bleeding risk.

  • Weight Loss Magic Soup Recipe – Great Vegetable Soup

  • STOP nicotine products 2 months before surgery. Ask your primary care provider for Chantix and Wellbutrin. These two medications taken together are highly effective in stopping nicotine cravings.

  • OPTIONAL: Start taking a probiotic 6 weeks prior to surgery or as soon as possible. You want one that has a minimum of 50 billion units and the more strains the more effective and discontinue 2 weeks before surgery.

Behavior/Lifestyle Changes

  • Discontinue ALL consumption of Dairy, Starches, Sugars, Desserts, and Fruit (with the exception of 1/2 cup a day)

  • Discontinue drinking ALL caffeine 2 weeks prior to your surgery date. Caffeine is a diuretic, which is acidic and may cause dehydration. 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

  • VERY IMPORTANT: Begin the practice of NOT drinking 30 minutes prior to/during/post meals. This should become a LIFELONG HABIT after Duodenal Switch surgery.

14 Days Prior to Duodenal Switch Surgery

  • Vitamins and herbal supplements must be stopped 2 weeks prior to surgery (based on your surgery date).

  • Discontinue birth control and FEMALE supplemental hormones (IUD’S & IMPLANTS ARE TOTALLY SAFE and do not need to be removed).

7 Days Prior to Duodenal Switch 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 our surgeon liaison.

For Diabetes Patients

  • May continue to take medication up to the day of surgery. Be mindful, medications and amounts may change due to diet and weight loss change prior to surgery.

  • MUST consult with their doctors about medication use.

  • MUST check sugar levels at home. If sugar is above 150, call your primary care physician immediately.

2 Days Prior to Duodenal Switch 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.

  • Sugar-free popsicles and sugar free jello (any color is acceptable)

8 Hours Prior to Bariatric 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.

Pre-Op Diet Guidelines

Here is a sample meal plan to help you get started on the pre-operative diet.

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

  • Breakfast: Options include 2 Whole Eggs, 1/2 an avocado, 1 Cup of Spinach (Raw or Cooked), or 1 Protein Shake

  • Mid-morning snack: 1 Protein Shake (limit 1-2 per day)

  • Lunch: 4 oz (110g – 170g) of lean protein, 2 Fist size of vegetables (fibrous carbs), 1-2 thumb size of fats

  • Dinner: Salad with Protein (chicken, fish, egg, etc.), a small amount of no or low sugar dressing (preferably olive oil & vinegar or Lemon)

  • Evening Snack: Apple slices with Almond Butter or Vegetables with Hummus

  • You may also add 1 TBSP chia seeds to your shakes or take psyllium husk to help you stay satisfied throughout the day.

  • * Patients with higher or lower BMI and/or other medical conditions may be prescribed other dietary prerequisites in addition to the above pre-op diet.

  • * You may at this time drink other drinks as long as they have NO SUGAR

Approved Proteins and Vegetables

Grass-Fed MeatCelery
LambBok Choy
90/10 Lean cut beefMushrooms
Lean pork
(Pork Tenderloin)
Wild Game
(Buffalo, Elk, Venison)
Organic PoultryAsparagus
Chicken BreastTomato
Eggs / Egg WhitesCauliflower
Egg SubstituteBell Pepper
Wild Caught SeafoodEggplant
ClamsBrussel Sprouts
LobsterGreen Beans
ScallopsBlack Beans
Protein AlternativesChickpeas
Vegan Protein PowderSpinach
Whey Protein PowderCucumber
Nuts & SeedsOnion
Beans (all varieties)Lettuce
Impossible Burger
Fairlife Milk

Approved Fats

Healthy Fats 

  • Avocado
  • Olive Oil
  • Nuts (Limit to a handful per serving)
  • Nut Butters (1 TBSP per serving)
  • Chia Seeds
  • Flax Seeds
  • Hemp Seeds

Recommended Protein Powders

Whey isolate and plant-based proteins are recommended. 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
  • Premier Protein
  • Non-dairy Muscle Milk
  • Naked Pea Protein

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