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USC Metabolic & Bariatric Surgery Program

Dietary Guidelines
Before & After Bariatric Surgery

Eat RightFeatured: Keck Medicine of USC is pleased to offer Outpatient Nutrition Therapy Services provided by a Registered Dietitian (RD) to assist you in managing your nutrition needs.
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The dietary guidelines following bariatric surgery is designed to limit calories consumed to help you achieve desired weight goal, at the same time prevent dehydration, nutrient deficiencies, preserve muscle mass, and avoid complications.

Prior to having surgery

It is important that you commit to a new healthy lifestyle. Modify or develop proper eating behaviors is vital to be prepared for the changes in the new digestive process after surgery, as well as to ensure long-term weight loss. A bariatric dietitian will be available to assist you in making these necessary changes.

New Eating behaviors:

  1. Eat slowly. Take 30 minutes to eat one meal
  2. Take smaller bites
  3. Chew food to a toothpaste consistency (25-30 chews) before swallowing
  4. Stop drinking fluids with your meals. Wait 30-45 minutes after your meal to begin drinking again
  5. Choose sugar-free drinks
  6. Choose non-carbonated beverages, avoid drinking from a straw, and avoid chewing gum
  7. Sip fluids. Do not gulp
  8. Choose high protein, low calorie, low-fat, and low sugar foods
  9. Use saucer size plates to reduce portions and junior size utensils to eat slower

After having surgery
Foods will be gradually reintroduced into your diet to allow your pouch to heal properly, avoid food intolerance, and avoid nausea or vomiting. The bariatric diet follows a low calorie, low-fat, low sugar, and high protein. Since food intake will be reduced, you will need to take daily vitamins and minerals lifelong to avoid nutrient deficiencies. Your lab tests will be done at 2 months, 6 months, one year, and annually thereafter to ensure you are receiving adequate vitamins and minerals in your diet. If you are deficient in certain nutrients, your dietitian will recommend additional supplements.  

Protein
It is essential that your body receives enough protein for healthy recovery, preserve lean muscle tissues, and prevent hair loss.  Examples of protein-rich foods are lean turkey, chicken, fish, egg whites, tofu, beans, legumes, cheese, nuts, yogurts, and cow’s milk. Your protein goal should be between 80-100 grams daily. Because you are now eating smaller portions, you will need to supplement with protein drinks for the first two to three months to help you reach this goal.

Vitamin Supplements
You must take the following vitamin supplements daily in order to prevent nutrient deficiencies. You need to take these vitamins in chewable or liquid form as whole pills are no longer absorbed orally due to the changes in absorption after surgery.

Multivitamins- You must take a high potency vitamin and mineral supplement that contain 18 mg Iron, 400 mcg folic acid, copper, and zinc per serving. Take two chewable tablets once daily the day after discharge.

Vitamin B12- Must be taken in sublingual form, nasal spray, liquid drops, or via injection. Take 1,000mcg sublingually once weekly or once monthly if given via injections.

Calcium Citrate with Vitamin D- Must take calcium citrate, the form that is easily digested and absorbed, not calcium carbonate. Your calcium citrate tablet must contain vitamin D (D3 is the active form) for best absorption of both supplements. Calcium supplements must be taken at least 2 hours apart to maximize absorption. Take 1500 mg daily to prevent calcium deficiency.

Vitamin D3- Take 2,000IU Vitamin D3, which is the absorbable form, once daily to promote healthy bone growth.

Iron- If your iron levels are low, you will be advised to take higher dosage of Iron.

  1. Iron is not absorbed when taken with calcium supplements and foods/drinks rich in calcium – for this reason, it is recommended to take at night, before bed
  2. Iron is best absorbed when taken with Vitamin C or foods/drinks rich in Vitamin
  3. Iron can cause constipation – try less constipating supplement from gluconate or fumarate forms
  4. All women and certain men need to supplement their diet with iron. Routine lab work will determine if you need to add additional dosage. Menstruating women are at greatest risk for developing iron deficiency anemia.

Vitamin B1- You are at an increased risk of experiencing vomiting the first two weeks after surgery, therefore Vitamin B1 supplementation is essential. Take Vitamin B1 100mg once daily to prevent deficiencies that can result in serious neurologic complications, such as beriberi and Wernicke’s encephalopathy.

Fluid
Your goal is to drink 48-64 ounces of sugar-free and caffeine-free liquids daily. Remember, you must wait 30-45 minutes after your meal to begin drinking again. Drinking liquids with meals or too soon afterward, may induce vomiting or regurgitation. It can also wash food through your pouch too quickly, reducing satiety. The amount of liquid you can consume at one time will also be limited. Sipping, not gulping fluids throughout the day will help prevent regurgitation and dehydration.

Diet Progression

STAGE I

3 Days post-surgery

Clear Liquid Diet

Sugar-free, decaffeinated, and low sodium clear liquids

 

Examples: Jell-O, popsicles, chicken, vegetable, or beef broth, tea, coffee, and water

Protein Drink

Clear liquid protein such as Isopure, liquacel, or prostat

Vitamin and mineral supplements

Start taking chewable or liquid vitamins:

  1. 1 chewable tablets of High Potency Complete Vitamins twice daily
  2. Calcium Citrate plus Vitamin D 1500mg once daily
  3. Vitamin D3 2,000IU once daily
  4. Sublingual Vitamin B12 1,000mcg once weekly
  5. Vitamin B1 100mg once daily

Goal

Sip slowly throughout the day. Aim for approximately 4-6 ounces of liquids per hour with the goal of 6-8 cups of fluids daily.

 

STAGE II

Day  4 to day 14 post-surgery

Full Liquid Diet

Thick liquids with smoothie consistency.
Choose thick liquids high in protein, low-fat, and low sugar.

 

Examples: non-fat yogurts, cream of wheat, low-fat creamy soups, blended oatmeal, sugar-free pudding, and low-fat cottage cheese

Protein

May drink creamy protein shake or powder, in place of liquid protein to meet protein goal.

  1. Protein powders can be mixed in one ounce of water or nonfat milk and then mixed with low-fat yogurt, oatmeal, cottage cheese, breakfast porridge, or soups
  2. Keep protein drinks in your bag, car, or traveling bag to have on hand when needed.

Vitamin and mineral supplements

Continue:

  1. 1 chewable tablets of High Potency Complete Vitamins twice daily
  2. Calcium Citrate plus Vitamin D 1500mg once daily
  3. Vitamin D3 2,000IU once daily
  4. Sublingual Vitamin B12 1,000mcg once weekly
  5. Vitamin B1 100mg once daily

Goal

Sip slowly. Aim for approximately 2 to 4 ounces (1/4 to 1/2 cup) of thick liquids at a time with the goal of 6-8 cups of fluids daily.

 

STAGE III

Day 15 to 5th week post-surgery, depending on type of surgery

Pureed Diet

Foods must be blenderized until a baby food consistency is reached. Goal of 6-8 cups of fluids daily.

Protein

May drink creamy protein shake or powder, in place of liquid protein to meet protein goal.

Vitamin and mineral supplements

Continue:

  1. 1 chewable tablets of High Potency Complete Vitamins twice daily
  2. Calcium Citrate plus Vitamin D 1500mg once daily
  3. Vitamin D3 2,000IU once daily
  4. Sublingual Vitamin B12 1,000mcg once weekly

*Stop Vitamin B1 at this point unless experiencing vomiting

Goal

These eating habits must be followed starting at this stage onwards:

  1. Aim for 1/2 to 3/4 cup of food at a time.
  2. Always eat protein first.
  3. If you are having protein shakes with a meal, drink the shake before eating foods
  4. Drink 30-45 minutes after or before your meal.
  5. Helps prevent food from being pushed through your system too fast, which can cause vomiting, gastric upset, and decreased satiety
  6. Chew foods thoroughly- 25 to 30 chews before. Chew until toothpaste consistency.
  7. Respect your new fullness cues. Stop when you feel satisfied. Do not wait until you are full. It takes 20 minutes for your brain to register that your pouch is full.
  8. Slow or stop eating upon pain or discomfort. Take small bites. Eat slowly
  9. Avoid spicy and acidic foods or drinks.
  10. Choose low sodium and caffeine-free products to prevent dehydration.

 

STAGE IV

Week 5 through 3rd month post-surgery, depending on type of surgery

Soft Diet

Foods must be well cooked and chopped into smaller pieces. Choose foods high in protein, low-fat, and low sugar.
Goal of 6-8 cups of fluids daily.

Protein

May drink creamy protein shake or powder, in place of liquid protein to meet protein goal.

Vitamin and mineral supplements

Continue:

  1. 1 chewable tablets of High Potency Complete Vitamins twice daily
  2. Calcium Citrate plus Vitamin D 1500mg once daily
  3. Vitamin D3 2,000IU once daily
  4. Sublingual Vitamin B12 1,000mcg once weekly

*Stop Vitamin B1 at this point unless experiencing vomiting

Goal

Begin developing a regular meal routine

  1. Aim for approximately 3/4 to 1 cup of food at a time.
  2. Eat three meals daily focusing on high protein choices to supplement your diet.

Stop blending foods. Moist foods (soaked in broth) are better tolerated.  Avoid nibbling and snacking throughout the day, as this leads to weight gain.

 

STAGE V

2 months to 3 months post-surgery, depending on type of surgery

Regular Solid Diet

May begin to incorporate regular textured foods such as raw vegetables and raw nuts.
Goal of 6-8 cups of fluids daily.

Protein

  1. You may discontinue your protein supplement ONLY if you eat at least 80g of protein per day through food sources
  2. If you are feeling tired, weak, or feeling cold, reincorporate protein drinks into your diet

Vitamin and mineral supplements

Continue:

  1. 1 chewable tablets of High Potency Complete Vitamins twice daily
  2. Calcium Citrate plus Vitamin D 1500mg once daily
  3. Vitamin D3 2,000IU once daily
  4. Sublingual Vitamin B12 1,000mcg once weekly

*Stop Vitamin B1 at this point unless experiencing vomiting

Goal

Introduce new foods to add variety.

  1. Aim for approximately 3/4 to 1 cup of food at a time.
  2. Eat three meals daily focusing on high protein choices to supplement your diet.

Helpful Tips:

  1. Trying one new food a day allows you to pinpoint food intolerances. If you feel that you are not able to tolerate a new food yet, wait one week and try that food again.
  2. Symptoms of food intolerance are stomach pain, nausea, and discomfort. People typically have difficulty tolerating bread, pasta, chicken, or red meat.

 

Long-term Post-operative Visit
You are required to attend follow-up appointments at 2 weeks, 2 months, 6 months, 1 year, and annually after surgery. Lab tests will also be completed at these times to ensure you are receiving adequate nutrition. We also encourage you to regularly attend our monthly support group meetings to discuss any barriers or challenges you are facing after surgery. Support groups also provide a great opportunity to share some of your success stories to help inspire others.

Contact our Registered Dietitians:

USC Metabolic and Bariatric Surgery Program
1450 San Pablo St.
HCC 4, Suite 6200
Los Angeles, CA 90033
Tel: (323) 442-5987

Additional Nutrition Information: 

 

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Healthcare Consultation Center 4
Suite 6200
Los Angeles, CA 90033

Phone: (323) 442-6868
Fax: (323) 442-6279


 
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