The purpose of this diet is to completely shrink the liver size prior to surgery in order to make the procedure have the highest success rate and lowest complication rate. This pre-op diet is effective in eliminating processed foods and sugars, therefore depleting stored glycogen.

Before surgery, it is very important to quit smoking at least 14 days before surgery

The Pre-Op Diet

Protein Drinks and Shakes

You may purchase these at most health food stores or grocery stores. Please be sure it contains at least 20 grams of protein per serving.  Sugar should be half the grams or less than protein- if you have 20 grams of protein, it should have less than 10 grams of sugar

The Basics

  1. 2 – 3 protein drinks per day
  2. You can eat as many raw or cooked vegetables as you want
  3. 2 – 4 oz. servings of lean protein (chicken, turkey, fish, lean ground beef)
  4. 1 – 2 servings of a 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 coconut milk (no regular milk- too much sugar)
  7. No bread, rice, pasta, refined grains, sauces with sugar, and no dairy (milk, yogurt, cheese)

Example Meal Plan

  • Breakfast: 1 protein drink or shake
  • Mid-morning Snack: 1 protein shake
  • Lunch: Raw or cooked vegetables (ok to add one TBSP olive oil or butter spray to veggies) and 4 oz.  Lean meat. Example: Tilapia with baked broccoli seasoned w/ olive oil and slivered almonds
  • Dinner: Salad with Protein (chicken, fish, egg, etc.), the small amount of no or low sugar dressing (preferably olive oil & vinegar or Lemon)
  • Evening Snack: 1 protein shake (if needed)

* Patients with a low or high Body Mass Index (BMI) and another medical comorbidity may be prescribed other dietary methods in addition to a pre-op diet.

* You may drink other drinks with NO SUGAR.

Behavior/Lifestyle Changes

  • Stop ALL carbonated beverages.
  • Stop ALL beverages with caffeine.
  • Begin physical activity or an exercise program – please talk to your doctor before.
  • Cut food into SMALL, chewable pieces and practice chewing foods into bitesize pieces.
  • Stop ALL Herbal supplements.
  • VERY IMPORTANT: Stop drinking 30 minutes prior to eating and DO NOT drink until 30 minutes after a meal.


7 Days Prior to Surgery Date

  • It is important to stop some medications before surgery. This will depend on your doctor or surgeon’s instructions. The certain medications to stop taking include Coumadin, Aspirin, Motrin, Ibuprofen, Advil, ANY ANTICOAGULANTS, OR BLOOD THINNERS Plavix, Nuprin, Aleve, or any other non-steroidal anti-inflammatory medication. **Note that this includes baby aspirin and most of the medications for arthritis. These can all cause stomach problems including irritation and possibly more bleeding postoperatively.
  • If you have specific medications you need to stay on prior to bariatric surgery, speak directly with your patient coordinator to get authorization from your surgeon
  • Stop taking ALL vitamins & supplements
  • Discontinue any supplemental hormones or birth control (both IUD’S  AND IMPLANTS ARE COMPLETELY SAFE  and do not need to be removed)
  • Use Tylenol as needed for a headache or minor pains before surgery
  • No herbal medications/remedies

Diabetes Patients

  • May continue to take medication up to the day of surgery. Be mindful, drugs and amounts may change due to diet and weight loss change before 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 Surgery: Clear Liquid Diet

  • Consume only clear liquids:
    • Water or clear juice without carbonation or pulp. (If you decide to drink regular juice, use 100% real juice and dilute 60/40 with water)
    • Clear broths like Chicken, Vegetable, or Beef.
  • Water or Flavored Water
  • 8 Hours before Surgery
  • Nothing to drink starting at midnight prior to surgery OR 8 hours prior to surgery.
  • No medications unless directed by the doctor or surgeon.
  • Please bring ALL your needed prescribed medications.

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