Bariatric Surgery Nutrition Handbook - revised 11192015 · 2016-02-08 · Pre-Bariatric Surgery...
Transcript of Bariatric Surgery Nutrition Handbook - revised 11192015 · 2016-02-08 · Pre-Bariatric Surgery...
Bariatric Surgery
Nutrition Handbook
Gastric Bypass and Gastric Sleeve
2
TABLE OF CONTENTS
Pre-Bariatric Surgery Diet 3
Choosing a Protein Supplement 5
Vitamin and Mineral Needs 6
Diet Stages Overview 7
Stage 1 Clear Liquids 8
Stage 2 Low Fat Full Liquids 9
Stage 3 Soft/Pureed Protein Foods 11
Stage 4 Soft Low-Protein Foods 13
Stage 5 Healthy Solid Foods 15
Label Reading 18
Dumping Syndrome 20
Tips for Success 21
Resources and References 22
3
PRE-‐BARIATRIC SURGERY DIET A Liquid Diet before Bariatric Surgery Ten days before your surgery you will need to consume only a liquid diet. This diet will cause rapid weight loss and also help reduce the size of your liver, making the procedure easier to perform and safer for you. The specific details of this diet will be given to you by your surgeon and reviewed by your nutritionist in your nutrition class. During this time, it is important to include a protein supplement several times each day to improve your nutrition before surgery. Your goal is 60-80 grams of protein each day. Some are pre-mixed and others are powder that requires mixing with fat-free milk or water. Please make sure you read the label on the supplement. You want to choose one that has a high amount of protein and a low amount of sugar and calories. Patients with diabetes that are taking oral diabetes medication and/or insulin should discuss the pre-surgery diet with the doctor that manages your diabetes. You may also choose to use products that are not low carbohydrate versions. Consume 15 grams of carbohydrate ever 1-2 hours to help prevent hypoglycemia. Make sure to monitor your blood sugar more closely as this is a very drastic change in your diet. Call your doctor if you are experiencing high or low blood sugars. The following page has a chart for you to use to track the foods and beverage you consume during this 10 day period. You will be consuming low and no calorie clear liquids and low fat, low calorie, no sugar added full liquids and a protein supplement. Clear Liquids Water
4
Diluted juices (fruit or vegetable) Broth based soups Gatorade or generic equivalent Sugar free flavored water Unsweetened tea Unsweetened coffee Crystal light Sugar free Gelatin Sugar free popsicles Full liquids Low fat, no sugar added yogurt Skim milk Low fat cottage cheese
5
6
CHOOSING A PROTEIN SUPPLEMENT While you are following the liquid diet prior to surgery and when you begin Stage 2 Low Fat Full Liquids you will need to drink a protein supplement. The supplement will need to be continued throughout the remaining stages of your diet in order to meet your protein needs. However once you are able to consume enough protein from foods at meal times you will no longer need a supplement. There are several to choose from and guidelines are provided to help you make your choice. Choose a ready to drink protein supplement or powdered protein supplement that contains: ▪ Protein from whey, casein, egg whites, milk or soy. Avoid collagen
or hydrolyzed gelatin.
▪ Less than 200 calories per serving.
▪ Less than 25 grams of sugar per serving.
▪ At least 15-20 grams but no more than 30 grams of protein per serving.
Some brand names available: Brand Amount Protein (g) Calories Sugar (g)
Ready to Drink Protein Supplement Slim Fast High Protein 10 ounces 20 180 2 Atkins Shake 11 ounces 15 160 1 Boost Glucose Control 8 ounces 16 190 4 Pure Protein 11 ounces 23 120 1 Isopure Plus 8 ounces 15 60 0
Powdered Protein Supplement Non-fat dry milk powder ⅓ cup 8 80 12 Pure Protein 1 scoop 20 110 1 Syntrax Nectar 1 scoop 23 100 0 Isopure Zero Carb Unflavored 1 scoop 26 110 0 Unjury Unflavored 1 scoop 21 90 0
7
VITAMIN AND MINERAL NEEDS Begin taking vitamin and mineral supplements with the Pre-Bariatric Surgery Diet. You will stop taking them the day before surgery but will start back during Stage 2 of the diet. All of the required supplements are listed below. They are available over the counter at your local pharmacy.
You will need to take these supplements every day from the start of stage 2 and for the rest of your life. Please remember that for the first TWO MONTHS you may not
swallow a whole pill.
MULTIVITAMIN AND MINERAL SUPPLEMENT
Amount and Type: We recommend Flinstones Complete because it has enough Iron and other vitamins that you need. Chew TWO tablets daily. How often: Every day When: In the morning with breakfast
VITAMIN B12
You will get a B12 injection before you leave the hospital and it lasts one month. After that you have these options: Amount and Type: 500 mcg sublingual daily or 1000 mcg every other day, nasal supplement weekly or 1000 mcg injectable once a month. The sublingual form is over the counter. If you prefer one of the other methods, you will need a prescription from your doctor. When: Oral type in the morning with breakfast
CALCIUM CITRATE WITH VITAMIN D
You will need to take at least 1200mg of Calcium CITRATE with D daily. Calcium Citrate in a chewable form can be difficult to find in local stores. You can find it online, but for your convenience, JCMC Pharmacy carries Opurity Calcium Citrate Plus D chewable. How much do I need?: 1200mg daily. You will chew 2 tablets with lunch and two with dinner.
8
How often: 2 tablets, twice a day When: With lunch and dinner (your Calcium should not be taken with iron or your multi vitamin as the absorption will be decreased). DO NOT PURCHASE ANY SUPPLEMENT THAT IS IN A GUM FORM. GUMMY CHEWABLES CAN BLOCK THE PASSAGE TO YOUR NEW STOMACH.
……
FLINTSONE COMPLETE CHEWABLES AVAILABLE AT OUR JCMC PHARMACY AND MOST LOCAL STORES. THE CALCIUM CITRATE PLUS D IS HARD TO FIND IN LOCAL STORES SO WE STOCK IT IN THE JCMC PHARMACY FOR YOUR CONVENIENCE. If you choose to buy your calcium online you will search for CALCIUM CITRATE in a chewable OR LIQUID form.
9
DIET STAGES OVERVIEW Your diet after surgery is important for successful weight loss. Your stomach is significantly smaller than before surgery and will limit the amount of food you are able to consume helping with weight loss. The nutrition prescription outlined below helps you in the following ways:
1. Preventing nausea, vomiting, and abdominal pain due to stomach blockage or stretching of your stomach.
2. Achieving and maintaining your desired weight loss. Your diet after surgery consists of five specific stages. Each step is described in detail on the following pages.
Stage
1 Day 1 in hospital
Clear Liquids
§ Three 1 ounce servings per meal.
Stage 2
Day 2 in hospital
Low Fat Full Liquids
§ Three 1 ounce servings per meal plus no sugar added Mighty Shake
Day 3 – 14 at home
Low Fat Full Liquids
§ Between meals drink 2 ounces of liquid every 15 minutes.
§ Goal is 48 ounces each day.
Stage 3 Week 3
Soft/Pureed Protein Foods
§ Add soft, pureed, high-protein foods to liquid diet.
10
§ Increase liquids to 48-64 ounces each day.
§ Consume 4-6 meals/day (1/4 cup each meal).
Stage 4 Week 4
Soft
Low-Protein Foods
§ Add well-cooked vegetables, soft/canned fruits.
§ Consume 4-6 meals/day (1/2 cup each meal).
Stage 5
Week 6 and beyond
Healthy
Solid Foods
§ Eat a balanced diet. § Avoid raw/fibrous fruits
and vegetables. § Consume 3 meals and 2
snacks (1 cup each meal).
TIME OF DIET ADVANCEMENT IS APPROXIMATE AND BASED ON YOUR TOLERANCE. YOUR DOCTOR MAY ADJUST THE TIME AS NEEDED.
STAGE 1 CLEAR LIQUIDS DAY 1 This stage begins in the hospital and consists of sugar free, caffeine-free, non-carbonated beverages.
• Clear liquids begin after the gastrograffin study (leak test).
• You will receive three 1 ounce portions of clear liquids at each
meal.
• Drink 1 ounce slowly over 15 minutes.
• Take small sips and be aware of feeling full.
• Avoid drinking from straw to reduce air intake.
Stage 1 foods include: • Broths – Chicken, Beef or Vegetable • Juice – Apple or Grape • Sugar Free Popsicles • Sugar Free Gelatin
11
STAGE 1 CLEAR LIQUIDS SAMPLE MENU
Breakfast Lunch Dinner 1 ounce vegetable
broth 1 ounce beef broth 1 ounce chicken
broth 1 ounce sugar free
gelatin 1 ounce sugar free
gelatin 1 ounce sugar free
gelatin 1 ounce apple juice 1 ounce sugar free
popsicle 1 ounce grape juice
STAGE 2 ADD LOW FAT FULL LIQUIDS DAY 2 -‐ 14 Stage 2 begins the second day after surgery and continues
until day 14.
• This diet stage is a combination of Clear Liquids and Full Liquids with the addition of your protein supplement.
• While in the hospital you will receive three 1 ounce portions of full liquids at each meal. Slowly increase the volume of full liquids at each meal to a maximum of 3 ounces.
• Be sure to stay hydrated by drinking 6-8 cups fluid each day between meals. You will need to drink small sips of water or sugar free, non-carbonated beverages throughout the day. Drink 1-2 ounces over 15 minutes. Do not drink more than 8 oz. fluids in one hour.
• Resume your chewable multivitamin, calcium citrate, Vitamin B12 and iron supplement.
• Your protein intake goal is 60-80 grams of protein/day.
12
• In the hospital, you will receive No Sugar Added Mighty Shakes to meet your protein needs. When you are at home drink protein-containing liquids and your protein supplement to meet you protein intake goal.
Protein Containing Full Liquids Sugar free,
non-carbonated Clear Liquids
Amount Food Protein (g) Water
8 ounces
Skim milk 8 Decaffeinated Coffee
8 ounces
No sugar added Carnation Instant Breakfast packet
mixed with skim milk 13 Decaffeinated Tea
8 ounces
Skim Milk mixed with ⅓ cup non-fat dry milk
powder 16 Broth
8 ounces
Soy milk 6 Crystal Light
6 ounces
Sugar free plain or vanilla yogurt 8 Sugar free Kool-Aid
8 ounces
Strained condensed low fat cream soup made
with skim milk 6 Sugar free gelatin
4 ounces
Sugar-free, fat-free pudding
4 Sugar free popsicles
100% fruit juice (no sugar added)
STAGE 2 LOW FAT FULL LIQUIDS SAMPLE MENU Breakfast Lunch Dinner
1 ounce no sugar added vanilla yogurt
1 ounce strained cream of chick soup
1 ounce tomato soup
1 ounce apple juice 1 ounce grape juice 1 ounce apple juice 1 ounce skim milk 1 ounce sugar-free
pudding 1 ounce no sugar
added vanilla yogurt After Breakfast After Lunch After Dinner 8 ounces protein
drink consumed over 1-2 hours
8 ounces protein drink consumed over
1-2 hours
8 ounces protein drink consumed over
1-2 hours 8 ounces sugar free,
non-carbonated beverage consumed
8 ounces sugar free, non-carbonated
beverage consumed
8 ounces sugar free, non-carbonated
beverage consumed
13
over 1-2 hours over 1-2 hours over 1-2 hours
Take your vitamin and mineral supplements.
STAGE 3 ADD SOFT/PUREED PROTEIN FOODS DAY 15-‐21
Stage 3 begins approximately 2 weeks after surgery and continues for 1 week.
• At this stage, you can slowly begin to replace full liquids with
soft, moist, pureed, high-protein foods.
• Consume 4-6 small meals throughout the day. Each meal should be ¼ cup.
• Consume protein first with the goal of 60-80 grams of protein per day.
• Eat slowly - each meal should take 30-45 minutes to finish.
14
• Chew thoroughly – swallowing chunks may cause stomach blockage.
• Avoid drinking 30 minutes before and 30 minutes after a meal.
• Increase clear liquids to 48-64 ounces each day.
• Limit high-fat, high-sugar foods as they may cause nausea.
• Add foods to your diet one at a time.
• Avoid extremes in food temperatures - very hot or very cold foods
may cause spasms or cramps.
• Avoid tough meats, hot dogs, bologna, bacon, sausage, peanut butter.
Food Portion Protein (grams) Scrambled Egg 1 8 Canned tuna - in water 1 ounce 7 White meat chicken or turkey
1 ounce 7
Low-fat/fat-free cottage cheese
½ cup 12
Low-fat/fat-free ricotta cheese
¼ cup 8
Low-fat/fat-free mozzarella cheese
1 ounce 8
Non-fat dry milk 1/3 cup 8 No sugar added/light yogurt
6 ounces 6
Sugar-free/fat-free pudding
½ cup 4
STAGE 3 SOFT/PUREED PROTEIN FOODS SAMPLE MENU
Breakfast Lunch Dinner ¼ cup Scrambled eggs ¼ cup Pureed Turkey ¼ cup Pureed chicken
30 minutes after Breakfast
30 minutes after Lunch
30 minutes after Dinner
8 ounces protein drink consumed over
1-2 hours
8 ounces sugar free, non-carbonated
beverage consumed over 1-2 hours
8 ounces protein drink consumed over
1-2 hours
15
Morning Snack Afternoon Snack Evening Snack ¼ cup Cottage Cheese ¼ cup Tuna with light
mayonnaise ¼ cup no sugar added
yogurt 30 minutes after
Snack 30 minutes after
Snack 30 minutes after
Snack 8 ounces sugar free,
non-carbonated beverage consumed over 1-2 hours
8 ounces protein drink consumed over
1-2 hours
8 ounces sugar free, non-carbonated
beverage consumed over 1-2 hours
Take your vitamin and mineral supplements.
STAGE 4 ADD SOFT LOW-‐PROTEIN FOODS DAY 22-‐35 This stage begins approximately 3 weeks after surgery. Continue stage 3 foods and slowly add soft low-protein foods to your diet. • Continue consuming 4-6 small meals per day. Each meal should be ½
cup.
16
• Continue keeping liquids and solids separated.
• Pay attention to your body’s feelings of fullness and stop eating when you begin to feel full.
Take your vitamin and mineral supplements.
Foods Allowed Foods to Avoid
Grains/Starches Cream of rice Bread Low-fat crackers Pasta Mashed low-fat potatoes without skin
Sweetened cereal
Cream of wheat Sweet rolls Oatmeal Croissants Low-fat tortilla High-fat crackers Malt-o-meal Sweet breads with nuts/dried
fruit Corn/rice based cereals (Corn Flakes, Rice Krispies, Special K, Kix, Cheerios)
Hash browns
Rice Granola High-fiber cereal Doughnuts Popcorn French fries Vegetables Tender-cooked vegetables Corn, celery, peas, lettuce,
stringy vegetables Carrots, broccoli, cauliflower, green beans, etc.
Fried vegetables
Tomato juice (<8 oz./day) Vegetables in cheese sauces Vegetables with tough skins or
large seeds
Foods Allowed Foods to Avoid Fruits Tender fruits Dried Fruits Bananas, cantaloupe, honeydew Fruit juice Unsweetened soft, canned fruits Fruits canned in heavy syrup Unsweetened applesauce Fruits with tough skins,
shells, or large seeds Miscellaneous Low-fat salad dressings Pies, cookies, cakes “light” fruit juices Sweetened/carbonated drinks
17
Jellies/candy/chocolate Potato/corn chips Ice cream
STAGE 4 SOFT LOW-‐PROTEIN FOODS SAMPLE MENU
Breakfast Lunch Dinner
¼ cup Scrambled eggs ¼ cup Oatmeal
¼ cup Pureed Turkey ¼ cup green beans
¼ cup Pureed chicken ¼ cup mashed
potatoes 30 minutes after
Breakfast 30 minutes after
Lunch 30 minutes after
Dinner 8 ounces protein
drink consumed over 1-2 hours
8 ounces sugar free, non-carbonated
beverage consumed over 1-2 hours
8 ounces protein drink consumed over
1-2 hours
Morning Snack Afternoon Snack Evening Snack ¼ cup Cottage Cheese ¼ cup canned peaches
¼ cup Tuna with light mayonnaise
1 low fat crackers
¼ cup no sugar added yogurt
¼ cup ripe cantaloupe
30 minutes after Snack
30 minutes after Snack
30 minutes after Snack
8 ounces sugar free, non-carbonated
beverage consumed over 1-2 hours
8 ounces protein drink consumed over
1-2 hours
8 ounces sugar free, non-carbonated
beverage consumed over 1-2 hours
STAGE 5 HEALTHY SOLID FOODS DAY 36 Stage 4 begins approximately 6 weeks after surgery and is the diet you will continue to consume to promote weight loss and maintain your nutritional health.
• Continue with stage 4 foods and introduce one food at a time from the list below. By adding foods gradually, you will notice if any particular food causes nausea.
18
• All foods in this stage should be low-fat, low in sugar, with a
variety of fruits, vegetables and whole grains, and provide 60-80 grams of protein per day.
• Food intolerances are individual and often temporary. Keep track
of foods that bother you and wait 2-3 weeks before introducing them again.
• Avoid distractions while eating (TV, reading, etc.).
• Chew foods to a pureed consistency before swallowing.
• Continue to keep solid foods separated from liquids with meals.
Take your vitamin and mineral supplements.
Foods Allowed Foods to Avoid
Meat/Dairy/Protein Scrambled/poached eggs Egg whites White meat chicken White meat turkey Broiled/baked fish Deli meats- low-fat Skim or 1% milk Sugar Free Carnation Instant Breakfast Soy milk Fat-free half & half Low-fat sour cream Light yogurt w/o seeds Sugar free pudding Low-fat cheeses Low-fat cottage cheese
Tough meats- roast beef, steaks, pork chops, roast pork Fried meats Hot dogs Bologna Sausage Bacon Spare ribs Regular cheese Peanut butter/nuts Whole/2% milk Chocolate milk Regular milkshakes, frappes, eggnog Half & half Regular sour cream
Foods Allowed Foods to Avoid Meat/Dairy/Protein continued Low-fat cream cheese Low-fat cream soups Low-lactose/lactose-free skim milk (if lactose intolerant
Regular yogurt Regular pudding Regular cheeses Regular cream soups Heavy cream
Breads/Grains/Starches Malt-O-Meal Cream of wheat
Granola Sweet roll
19
Cream of rice Oatmeal Corn/rice-based cereals (corn flakes, Kix, Cheerios, Rice Krispies, Special K) Low-fat crackers Low-fat tortilla Mashed, low-fat potato Baked potato without skin Pasta Toast Low-fat popcorn- chewed thoroughly
Doughnuts Croissants Sweet breads with nuts or dried fruit Pancakes/waffles with regular syrup High-fat crackers French fries Hash browns Macaroni and cheese Pasta with alfredo Butter crackers- goldfish, wheat thin, etc. Potato chips, tortilla chips, cheese curls
Vegetables Any soft-cooked, plain vegetable Tomato juice (<8 oz./day) Reintroduce salad and raw vegetables slowly
Fried vegetables Vegetables in cheese sauces Vegetables cooked in fat or cream sauces olives avocados raw vegetables with tough skins, stems, or seeds
Fruits Tender fruits- bananas, cantaloupe, honeydew Unsweetened soft, canned fruits Unsweetened applesauce Fresh fruits- introduce gradually
Fruits with tough skins, shells, or large seeds Dried fruits Fruits canned in heavy syrup Fruit juice Coconut
Miscellaneous Broth Sugar-free gelatin Herbs/spices Lemon juice
Cream soups/chowders Regular gelatin Pies Cakes, cookies
Foods Allowed Foods to Avoid Miscellaneous continued Low-fat margarine, mayo, salad dressings Sugar-free popsicles Light fruit juices Crystal light Decaf coffee/tea
Butter/margarine/cream cheese/sour cream Salad dressing Nuts Potato/corn chips Chocolate/candy Ice cream Jam/jellies Honey/sugar
20
Gravy Alcohol Carbonated/caffeinated drinks of any kind (diet and regular) Gatorade/Snapple/So-Be Sweetened coffee drinks Sweetened ice tea
STAGE 5 HEALTHY SOLID FOODS SAMPLE MENU Breakfast Lunch Dinner
¼ cup Scrambled eggs ½ cup oatmeal 1 slice toast
2 oz. deli meat Turkey
½ cup green beans 2 oz. low fat yogurt
2 oz. chicken ¼ cup cooked carrots
¼ cup mashed potatoes
30 minutes after
Breakfast 30 minutes after
Lunch 30 minutes after
Dinner 8 ounces protein
drink consumed over 1-2 hours
8 ounces sugar free, non-carbonated
beverage consumed over 1-2 hours
8 ounces protein drink consumed over
1-2 hours
Afternoon Snack Evening Snack 8 ounces sugar free,
non-carbonated beverage consumed over 1-2 hours
¼ cup Tuna with light mayonnaise
3 low fat crackers ¼ cup applesauce
2 oz. low fat cheese ¼ ripe banana
30 minutes after Snack
30 minutes after Snack
8 ounces protein
drink consumed over 1-2 hours
8 ounces sugar free, non-carbonated
beverage consumed over 1-2 hours
LABEL READING Many foods appear healthy but may actually contain a high amount of sugar, calories, or fat. Although these nutrients are important, having too much in your diet can cause weight gain. When choosing a food, read through the ingredients and Nutrition Facts for a description. Serving Size
21
Look at the number of servings in a package. The amount of calories, fat, and sugar on the nutrition facts label is only for one serving. Many packages contain more than one serving. Calories This number is the total calories in one serving of the food. When you advance to stage 4, meals should be 300-400 calories each. Snacks between meals should be 100-200 calories. Total Fat For optimal health, limit your overall fat and choose healthier fats. Saturated and trans-fats (animal products, hydrogenated oils) are linked to heart disease and should be limited. Look for polyunsaturated and monounsaturated fats (olive and canola oil) which are better choices. Low-fat foods contain 3 grams fat/100 calories or less. Total Carbohydrate Carbohydrates include natural sugar, added sugars, fiber, and sugar alcohols. While added sugars may cause dumping syndrome, fiber passes through your body and helps to prevent constipation. Choose foods high in fiber when you are on solid foods, but chew all fiber-containing foods thoroughly. Protein Since your protein goal is 60-80 grams/day, try to have 20-25 grams of protein per meal. By choosing a variety of protein foods, drinks, and snacks, you can meet this goal.
22
DUMPING SYNDROME
23
Dumping syndrome commonly occurs after bariatric surgery. Food that contains a high amount of sugar, fat, or lactose may be “dumped” into the small intestine. Dumping syndrome has two phases and can be unpleasant. If you experience either phase, determine which food caused it in order to prevent it from happening again. Initial Phase: 15-60 minutes after a meal
• Nausea • Abdominal cramps • Cold sweats • Increased heart rate • Flushing • Vomiting • Diarrhea
Latent Phase: 2-4 hours after eating
• Cold sweats • Lightheaded/dizzy feeling • Shakiness • Weakness • Hunger
The latent phase may mean that you have a low blood sugar or hypoglycemia. When you notice latent dumping syndrome, use the 15/15 rule.
1. Consuming 15 grams of carbohydrate Examples: 4 oz. juice, 8 oz. low-fat milk, 8-10 lifesavers
2. Wait 15 minutes If symptoms persist, repeat the 15/15 rule. Don’t over-treat a low blood sugar as it may cause you to “dump” again.
Troubleshooting Not everyone experiences dumping syndrome but you may have some of the symptoms of dumping listed above. When you notice symptoms, ask yourself the following questions: When did I last eat? What foods/beverages did I have? Were those foods high in sugar, fat, or lactose (dairy)? What was the total amount of carbohydrate in the meal? If I had symptoms of latent dumping, did the 15/15 rule help resolve symptoms?
24
TIPS FOR SUCCESS
• Give yourself 30-45 minutes for each meal. Take small bites and chew well before swallowing. Notice when you start to feel full.
• Do not drink fluids with meals. Wait at least 30-45 minutes before or after meals to drink beverages
• Sip on at least 48-64 oz. calorie-free and non-carbonated fluid between meals to stay hydrated
• Take your vitamins and minerals every day
• If you find that you’re not losing weight, keep a record of everything you eat and drink throughout the day.
• Avoid temptation! At every meal, prepare your plate and then put leftovers away before you begin to eat.
• Buy individual portions or small packages of food to control your intake.
• When eating at a restaurant, use the following tips to stay on track:
o Share a meal o Avoid beverages with meals o Avoid the bread basket o Avoid appetizers- many are high in fat o Choose lean meats and lighter entrees o Avoid dips, sauces, or gravies or ask for them on the side o Avoid buffets o Take leftovers home
25
RESOURCES
www.nih.gov (National Institutes of Health) www.eatright.org (American Dietetic Association) www.mayohealth.org (Mayo Clinic) www.americanheart.org (American Heart Association) www.diabetes.org (American Diabetes Association) www.niddk.nih.gov/health/nutrition.htm (National Institute of Diabetes, Digestive & Kidney Disorders)
REFERENCES
Cummings, Sue, and Kellene Isom. Pocket Guide to Bariatric Surgery. 2nd ed. N.p.: Academy of Nutrition and Dietetics, 2015. Print. "Gastric Bypass Surgery Nutrition Handbook." Dartmouth-Hitchcock Medical Center, 23 Feb. 2005. Web. 8 Sept. 2015. Van Nieuwenhove, Y., et. al. (2011). Preoperative Very Low-Calorie Diet and Operative Outcome After Laparoscopic Gastric Bypass. A randomized Multicenter Study. Arch Surg, Vol. 146 (No.11). Van wissen, J. et. al. (2015) Preoperative Methods to Reduce Liver Volume in Bariatric Surgery: a Systematic Review. Obes Surg DOI 10.1007/s11695-015-1769-5.