Dietary Guidelines

Two red apples

Obesity surgery doesn't eliminate dieting altogether. It means that if patients adhere to the prescribed diet for the rest of their lives, they'll lose the excess weight and keep it off. On the contrary, if you ever go off the diet, you will gradually regain the weight lost.

It’s important to start implementing this diet even before the surgery because pre-surgery weight-loss helps the surgeon by making the laparoscopic approach easier and safer and increases the likelihood that the surgery can be completed less invasively.

Other dietary requirements are basic common sense eating. With sensible eating and exercise habits (three healthy meals a day with healthy snacks), the weight-loss can be easily maintained after surgery.

The long-term goal of weight-loss surgery is to lose approximately 70 to 80 percent of your excess weight. The end result of gastric bypass surgery is that patients will continue to require only small portions of food and eventually be able to tolerate all types of foods. Patients’ bodies will be satisfied with smaller amounts of food and they won’t have continued cravings for larger quantities of food at mealtimes.

Remember that this program is an individual process and patients may not progress from one diet plan to the next in the exact time frame given. Adapting to new foods won’t happen overnight, it’s a learning process. Also, keep in mind it takes approximately six months before the body will be able to tolerate all types of foods, especially meats, and it’s possible you won’t tolerate eating some foods at all.

Post-Surgery Dietary Plan

  • Your bariatric surgery dictates that small amounts are eaten.
  • Only nutrient-dense items are allowed on the bariatric eating plan.
  • It’s imperative that food be eaten slowly and in very small quantities at mealtime.  Take 30 minutes for each meal.
  • To prevent dehydration, strive to drink at least 6 cups of water each day. Sip fluids.
  • Stop sipping liquids within 30 minutes of each mealtime (once you reach the pureed diet stage).
  • After surgery, lifelong multivitamin and mineral supplements are recommended.

Bariatric Clear Liquid Diet

While in the hospital, you will drink out of medicine cups. Start out by sipping 30 mL over the course of 30 minutes. It should take eight to ten sips to finish the first medicine cup. Increase your sipping rate as able.

The following clear liquids can be consumed during this phase:

  • Water/ice chips
  • Skim milk
  • Clear broth

Bariatric Clear Liquid Diet Guidelines

  • During this period, you need to drink 3 cups skim milk and 6 cups water each day to prevent dehydration.
  • Take your time and sip slowly.
  • Walking can help liquid move out of stomach pouch. Walk at least 30 minutes each day.

Bariatric Full Liquid Diet

You will go home on a bariatric full liquid diet. You can drink out of regular glasses, but continue to take very small sips. The goal is to drink 24 ounces of double milk (8 oz skim milk plus 1/3 cup nonfat dry milk powder) and at least 48 ounces of water each day at home.  Keep track of your intake on the form we provide you.

Do not use straws. Do not gulp liquids or drink quickly. This can cause abdominal pain and intense nausea.

Examples of Bariatric Full Liquid Diet foods include:

  • Low fat cream soups (blended and strained and made with double milk)
  • Sugar free pudding (made with double milk)
  • Smooth light yogurt (preferably Greek)
  • Anything allowed on the clear liquid diet

Your meal plan will consist of three small meals and 8 ounces double milk for snacks three times a day. The recipe for double milk is: 1 cup skim milk with 1/3 cup nonfat dry milk powder added. Flavor these with no-sugar-added powders or syrups, as desired. Continue to drink at least 6 cups plain water per day.

Start your vitamin/mineral supplements day 8 after surgery

Vitamins suggested status post gastric bypass:

  • Chewable/softgel calcium (600mg) with Vit. D (400 IU) three times a day
  • Chewable/softgel complete multivitamin twice a day
  • Vit. B12, 500 mcg tablet once a day
  • Vit. B-complex tablet once a day
  • Iron (65mg iron or 325 mg ferrous sulfate) once a day
  • Vit. D tablet 1000 IU once a day

Vitamins suggested status post gastric sleeve:

  • Chewable/softgel complete multivitamin once a day
  • Vit. B12, 500 mcg tablet once a day
  • Vit. D tablet 1000 IU once a day.

Bariatric Full Liquid Diet Suggestions

  •  During this period, you need to eat three very small meals a day. Initially 1 to 2 tablespoons of food may be all your body is able to tolerate. Stop if you feel a full pressure. Do not take an extra bite.
  •  Take your time and eat slowly.
  •  Walking can help food move out of stomach pouch.
  •  Overall goal is to get 100 grams of protein and 100 grams carbohydrate each day, but you are doing well to get over 50-60gms of protein and carbs at this stage. Drinking 3 cups double milk each day provides 48 grams protein and 72 grams carbohydrate. These can be consumed hot, cold or flavored in a variety of ways.
  •  If you feel gassy, bloated or have loose stools on this diet, it may be lactose intolerance. This is generally temporary. Take Lactase enzyme tablets (such as Lactaid) or eat yogurt or try soy milk or lactose-free milk to alleviate symptoms.
  • Constipation is not uncommon on this diet. Add Benefiber, FiberSure or Metamucil-Smooth to each double milk to promote regularity.

Keep walking to promote regularity, as well. Walk at least 30 minutes/day.  If you lift weights, you need to lift less than 10 lbs and avoid any abdominal exercises.

Bariatric Pureed Diet

On the third week after surgery, you will advance to puree consistency; you will eat three small meals; you will drink 8 ounces of skim milk for snacks three times a day. You can always drink double milk or eat Greek yogurt if your protein/carbohydrate intake is low. Keep striving to get 100 grams protein and 100 grams carbohydrate/day.  Continue to drink at least 6 cups plain water per day. Do not drink with a meal, for 30 minutes prior to a meal or 30 minutes after a meal.

Bariatric Pureed Diet foods include:

  • Mashed potatoes
  • Unsweetened applesauce
  • Refried beans
  • Cottage cheese
  • Scrambled egg (light and fluffy)
  • Farina (Cream of Wheat or Malt-O-Meal-plain, not flavored)
  • Pureed meats (puree ¼ cup broth with ¼ cup chopped meat)
  • Pureed vegetables (puree ¼ cup vegetable with water or broth)
  • Pureed fruits (puree ¼ cup fruit with 2 to 4 tablespoons of water)

When you start the pureed diet:

  • Eat protein food first (3 ounces (21 gm) per meal); carbohydrates second (15-20 gm/meal)
  • Continue to strive to get 100 grams protein and 100 grams carbohydrate per day
  • Make your last milk a double milk if you don’t have 100gms protein in by end of day

Bariatric Soft Diet

One month after surgery, your diet will consist of three small meals (3 to 4 ounces or 1/3-1/2 cup each) and 8 ounces skim milk for snacks three times a day. Continue to drink at least 6 cups plain water per day. Do not drink with a meal, for 30 minutes prior to a meal or 45 minutes after a meal. Chew food to puree consistency.

Bariatric Soft Diet foods include:

  • Well cooked vegetables (no skin)
  • Canned fruits (in own juice or light syrup) or ripe fruit (no skin)
  • Fish
  • Tender meats/poultry (cook in water, crock pot or slow cooker)
  • Anything allowed on the pureed, full, or clear liquid diets

When you start the soft diet:

  • Eat protein food first (3 ounces per meal (21 gm); 9 ounces total)-100 gm/day
  • Eat carbohydrate second (15-20 gms/meal)-100 gm/day
  • Chew your food to puree consistency. Take 20-30 chews before swallowing.
  • Add variety and intensity to your exercise. This is the time to add heavier weights.
  • Make your last milk a double milk or a Greek yogurt if you don’t have 100 gms protein/carbs by end of day

Bariatric General Diet

Eight weeks after surgery, your diet will consist of three small meals (3 oz protein and 1 carb serving each) as well as 8 ounces of skim milk for snacks three times a day. Continue to drink at least 6 cups plain water per day. Do not drink with a meal, for 30 minutes prior to a meal or 30 minutes after a meal. Chew food to puree consistency.

Bariatric General Diet foods include:

  • Vegetables (no skin)-eat only those you can chew to mush
  • Fruit, canned or fresh (no skin, in own juice or light syrup)-only those you can chew to mush
  • Fish/Tender meats/poultry (may want to cook in water, crock pot or slow cooker)
  • Anything allowed on the soft, pureed stages

When you start the general diet:

  • Eat protein food first (3 ounces per meal (21 gm), 9 ounces total); carbohydrates second (1 serving/meal (15-20 gm))
  • Chew your food to puree consistency. Take 20-30 chews before swallowing.
  • Continue to add variety and intensity to your exercise.
  • Bread, rice and pasta often are poorly tolerated (toast, tortillas or pita bread may be better tolerated)
  • Tough, dry meats are poorly tolerated

Bariatric Surgery Resources

Contact Us

Bariatric Surgery
University of Iowa Hospitals and Clinics
200 Hawkins Drive, 4604 JCP
Iowa City, IA 52242
Phone: 319-356-1887
Fax: 319-353-6192