Dietary & Nutritional Guidelines

After weight loss surgery it is important for the patient to follow the dietary and nutritional guidelines recommended by his or her doctor. Each patient will be expected to change the foods eaten, the amount of food eaten, and how that food is eaten, in order to provide the body with the nutrition it needs and to promote weight loss. Theses dietary changes and nutritional guidelines are meant to be followed for a lifetime.

The diet after weight loss surgery will gradually progress from liquids to purees to solid foods. The amount of time it takes before a patient can add solid foods to the diet will vary somewhat based on the patient and the procedure, but generally weight loss surgery patients are eating small amounts of solid food 4-6 weeks after surgery. Following your surgery, your doctor will monitor your recovery carefully to determine what foods are appropriate for you and provide you with specific dietary guidelines.

Although specific dietary guidelines will vary for each procedure and each patient, the guidelines below are some of the general dietary changes weight loss surgery patients might expect after weight loss surgery.

Healthy Food Choices

The diet after weight loss surgery will primarily consist of low-fat proteins (lean meats such as chicken, turkey, and fish) and fruits and vegetables. Your doctor will provide you with a list of foods that can be eaten after surgery, including healthy protein choices, healthy carbohydrates, and heart-healthy fats. It is important to consume a sufficient amount of protein to help maintain muscle and burn fat, and to choose lean protein foods because they are lower in calories. Since you are only eating a small amount of food, it is important to choose foods that are healthy.

Eating Habits & Behaviors

After surgery, how you eat will change just as much as what you eat. Your stomach will only be able to hold a small amount of food at any one time and your digestion process has been changed.

  • Meal portions must be small, you must eat slowly, and food must be chewed thoroughly. If you eat too much, eat too fast, or don't completely chew your food (your body is not able to break down foods that have not been chewed to a liquid consistency), it may cause nausea or vomiting.
  • Avoid drinking liquids with meals. Liquids do not relieve hunger and may force food through your stomach pouch too quickly. This may cause you to become hungry during the day. It may also cause dumping syndrome in gastric bypass patients. Do not drink 30 minutes before or 30 minutes after a meal.
  • Set a time for three meals a day, and eat only at those scheduled meal times. Do not skip meals. Do not snack between meals.
  • When you feel full, stop eating. If you overeat, not only can it cause nausea and vomiting, but it can stretch out the size of your stomach pouch. When you first start on your solid diet, you may only be able to eat 4 to 6 bites of food before you feel full. With time, you may be able to eat a half cup up to one cup of food.

Nutritional Supplements

You will need to supplement your diet with vitamins and minerals for the rest of your life. Lap band patients will need to take a daily multi-vitamin supplement, whereas gastric bypass patients will need to take daily supplements including a multi-vitamin, calcium, vitamin B12, and additional iron. Protein supplements are also recommended. Protein supplements include whey protein powder, whey isolate (for lactose-intolerant), lactaid milk, soy milk and other soy products.

Drinking Water and Other Liquids

It is important to stay hydrated and drink 6-8 cups of water daily. Water must be sipped slowly, no more than 1-2 small mouthfuls at a time (approximately 1/4 - 1/2 cup total). Other approved liquids include tea, sugar-free flavored drinks, and sugar-free sport drinks. Drink plenty of fluids between meals, but avoid liquids with meals. Carbonated beverages should be avoided as they may cause gas, bloating, pain, and may contribute to enlargement of the small stomach pouch. Alcohol should be avoided because of the excess calories as well as the possibility of dumping syndrome and addiction.

Bariatric Diet of Grilled Salmon with Vegetables
Since you are only eating a small amount of food, it is important to choose foods that are healthy.

Dumping Syndrome

Dumping syndrome occurs when foods enter the small intestine too quickly and causes nausea, weakness, abdominal cramping, headache, sweating, faintness, and eventually diarrhea. It may be caused by eating sweets, fried foods, fatty foods, greasy foods, eating too much at one meal, or drinking fluids with meals. Depending on how you view this effect, dumping syndrome can be considered both an advantage or disadvantage of gastric bypass surgery. Lap band patients do not experience dumping syndrome.

Foods to Avoid

It is important to avoid sugary foods (candy, ice-cream, cookies, cakes, syrups), high-fat foods (chips, fried foods, sausage, cream soups, sauces, gravies, margarine, mayonnaise, junk food), fibrous foods (asparagus, pineapple, rhubarb, oranges, dried fruit), and other problematic foods (tough or overcooked meats, doughy breads, pasta, rice, skins and seeds of fruits and vegetables, nuts and popcorn).

Follow Up Tests

There are long term nutritional effects with weight loss surgery and you will need to have your blood checked several times in the first year and once a year for the rest of your life to make sure you are adequately absorbing your vitamins and minerals. Nutritional deficiencies may occur over time and periodic life-long checks are necessary. Follow-up tests will check for many things including anemia, coagulation function, electrolytes, liver function, thyroid function, cholesterol, levels of vitamin, minerals, micronutrients, and iron in the blood.

Bariatric Counseling and Support Groups

Weight loss surgery patients are usually advised by their bariatric surgeons to participate in both nutritional and psychological counseling as part of their weight loss treatment. Nutritional counseling helps a patient learn healthier eating behaviors and make healthy food choices. Psychological counseling helps a patient deal with the emotional issues that contributed to obesity. Nutritional and emotional support after weight loss surgery is very important to a patient's success. Another helpful source of support is to stay in contact with other weight loss surgery patients at support groups or on-line forums.

Low Calorie Diets and Exercise

Exercise has many health and weight loss benefits. Following weight loss surgery, you will be eating less food than your body needs to operate. The body will then use fat reserves or unused tissues to get the energy it needs to function. If you do not exercise the body will consume unused muscle tissue before it burns fat reserves. You must exercise daily or you will lose muscle mass and strength. Muscle tissue is important to keep because it provides strength and also increases your body's metabolism to help burn calories.

Weight loss surgery patients are usually advised to exercise aerobically (brisk walking, bike riding, stair climbing) 30 minutes a day and include weight/resistance training 3-4 days per week. Your bariatric surgeon will provide you with exercise guidelines, but most weight loss surgery patients are asked to start walking as soon as possible after surgery and slowly progress to a full work-out schedule as they recover.