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Bariatric care: Roux-en-Y gastric bypass surgery

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After having gastric bypass surgery, you should be aware of possible problems like these:



It is usually caused by:

  • eating too fast
  • eating too much
  • not chewing food to the consistency of applesauce
  • drinking liquids with meals
  • stomal stenosis (narrowing of the opening from the pouch to the intestines)

Keeping a food journal will help you figure out if vomiting is caused by food. You can avoid vomiting by chewing well, waiting 45 seconds between bites, and limiting the size of the bite you put in your mouth. Call your surgeon if you are vomiting often.

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Clogging (food blockage)

This can happen when you haven’t chewed food well enough and it gets stuck in the outlet between your pouch and intestines.

Usually, the food will dissolve by itself or will work its way through on its own. However, while the food is clogged, it can be very uncomfortable.

Clogging can cause vomiting and retching.

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Dumping syndrome

Some people experience an intolerance to foods that are high in sugar (sweets), fat or grease. When you eat these foods, they now enter your intestines without being partially digested by the gastric juices of your old stomach.

Dumping usually occurs shortly after eating, in five to 15 minutes. When this happens, you may have nausea, vomiting, have a hot flash, cramps or diarrhea. This reaction is so unpleasant you will want to avoid foods that caused the dumping syndrome. These foods have higher calories and can lead to weight gain.

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Reactive hypoglycemia

This is a set of symptoms that results from low blood glucose. It happens 45 to 60 minutes after eating a meal, especially one that is high in carbohydrates. Symptoms you may feel include.

  • sweaty
  • jittery
  • lightheaded
  • your heart is racing

There is an imbalance between blood glucose and insulin in your bloodstream. Insulin is a hormone that allows glucose to be used. But the insulin stays in the blood after the glucose from the meal has been used. This causes low blood glucose, or hypoglycemia.

  • To treat reactive hypoglycemia, take two ounces of diluted juice or two ounces of skim milk.
  • To prevent reactive hypoglycemia, avoid simple carbohydrates like sweets, desserts, candy, non-diet pop, caffeine and alcohol. Eat three well-balanced meals that include protein, whole grains, fruits and vegetables. Eat the protein first. If the symptoms continue, call your surgeon or bariatric nurse clinician.

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Alcohol use

You should avoid alcohol for the rest of your life. Alcohol has empty calories which can slow weight loss or add to weight gain. It can also damage your liver or even cause death.

Alcohol can keep your body from absorbing many vitamins and minerals. There is a risk of addiction to alcohol after surgery that could affect your health, relationships and well-being.

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Transfer behaviors/Cross addiction

Many people use food to satisfy emotional needs. When this is no longer possible after weight loss surgery, it is possible to use other behaviors instead. Some of these behaviors might include alcohol abuse, excessive shopping, excessive gambling, or promiscuous sexual behavior. These behaviors can be damaging and dangerous. Do not delay in seeking help.

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Weight gain

Eating high-fat or high-calorie foods, carbohydrates and foods that have added sugars may cause you to gain weight. Eating too often or eating portions that are too large will also cause weight gain.

  • Avoid all foods cooked in lard, bacon grease, Crisco®, butter, margarine or oil. Try using Molly McButter®, Butter Buds® or a reduced-calorie margarine to season foods.
  • Read food labels carefully. The terms "sugar-free" and "fat-free" can be misleading. While they have reduced fats or sugars, they will add significant calories if eaten often, even in small amounts.
  • Pay attention to portion size listed on labels. Some labels list a tiny amount as one portion.
  • Avoid all foods and liquids with added sugar, or sugar as one of the first three ingredients listed. "Sugars" include any compound ending with "ose" (glucose, dextrose, sucrose, fructose or maltose), as well as corn syrup and hydrolyzed starch.
  • Avoid eating all the time (grazing) or unplanned snacks. It is possible to overeat and gain weight.
  • Watch how much fat you eat. Fats have more than two times the calories of carbohydrates or protein. Try to keep your total fat intake to fewer than 30 grams each day.
  • Watch for hidden fats. Salad dressing, gravy, sauces and baked foods can have hidden fats.

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Constipation after gastric bypass surgery is common.

Because of the small amount of food you are eating, it is common to have a bowel movement only every two to three days. If constipation becomes uncomfortable, it is OK for you to take milk of magnesia. If your stools are hard, include some high-fiber foods in your diet (see below). Be sure to drink at least 64 ounces of water each day between meals.

The American Dietetic Association recommends 20 to 35 grams of fiber every day.

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Gas problems are also common. If you have gas pains try simethicone drops, Bean-O® or Gas-X®. Also, avoid dairy products (milk, cheese and ice cream), carbonated beverages, straws and chewing gum.

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During rapid or large weight loss, your risk of making gallstones goes up. Gallstones are clumps of cholesterol and other matter that form in the gall-bladder. You might feel a steady, severe pain on the right side of your abdomen going to your back. This pain will start after eating a meal. You might also feel bloated or nauseated and vomit. Call your surgeon if these symptoms continue.

Your surgeon may prescribe a medication called Ursodiol (or Actigall). You may take this medication for six months after surgery to prevent gallstones from forming.

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Problem foods

You may have problems with:

  • tough meats, such as beef or hamburger
    • Try marinating solid meats or use a tenderizer.
    • Cook at a lower temperature for a longer period of time.
    • Spit out anything that doesn’t liquefy in your mouth after chewing.
  • membranes of oranges and grapefruit
    • Use only pulp-free juice.
    • Spit out unchewable membranes.
  • skins and seeds of some fruits and vegetables (Strawberry seeds seem to be okay.)
  • fibrous vegetables such as corn and celery
    • Use a blender or strainer.

    Avoid eating:

  • fresh bread
  • pasta and rice
  • fried foods
  • chicken skin, bratwurst skin, hot dog skin, etc.

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Hibernation syndrome

Two to four weeks after surgery, your body reacts to the smaller amount of food you are eating. You feel tired, lethargic and often depressed. Your body wants to slow down until the old food supply returns.

The best way to deal with this is to know the symptoms and know they are normal. Start to exercise so your body gets used to using body fat as a source of energy. Call your program staff if your symptoms last longer than six to eight weeks.

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Other body changes

When you don't eat enough protein, you will notice some changes in your hair and nails because they are made of protein. Try to eat at least 60 grams of protein each day. You may:

  • get flaky and weak fingernails
  • have hair loss between the third and ninth months after your surgery. Your hair will grow back.
  • lose muscle mass

If you are a women, your menstrual cycle may be irregular and may come right after surgery. This is normal.

Pregnancy is not advised for two years after surgery. Use effective birth control.

You may not be able to drink milk or eat dairy products after surgery because they have lactose (a natural sugar) your body may reject. This may be short- or long-term.

You may get lightheaded or dizzy when you get up from a chair or bend over. This is caused by not drinking enough water and should be temporary.

You may feel shaky, faint, or have a headache.

  • This could be caused by hypoglycemia (low blood glucose) and can be helped by drinking skim milk or watered down orange juice or by eating a protein bar or graham bar. You may have low blood glucose symptoms if you skip a meal or don't eat before exercising.

You may have extra (loose) skin.

  • You can help keep your skin healthy by not smoking, drinking plenty of water, and eating a well balanced diet. Exercise and weight training will help tone your skin and improve how the extra skin looks. If extra skin is a problem for you, talk with your surgeon.

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Emotional issues

As your body changes so dramatically, you will be changing emotionally, too. Some people find these changes disturbing.

Obese people have sometimes used their size to hide from life, to insulate them from the outside world. Losing weight can make you feel vulnerable at times.

If you are having trouble dealing with emotional issues, find someone you trust to share your feelings. It may help to seek professional counseling. This will help you go through the changes more smoothly and help you to be more successful with your weight loss. Emotional issues you may have include:

Depression after weight loss surgery is common.

  • For some women, estrogen (a hormone) is released while fat is burned to make energy. This release of estrogen may cause mood swings.
  • People who eat as a way to manage their emotions (known as emotional eaters) may be depressed because they can no longer eat like they used to.
  • If you take a mood stabilizing medicine, it is important to keep taking it after surgery. Do not stop taking medicines without talking to your health care provider. You may need a dose adjustment of your medication after surgery as absorption of the drug may be affected by surgery.

Partner jealousy Your partner may have a hard time dealing with the new you. Not only has your body changed, but you may be changing emotionally as a result of your increased self-confidence and self-esteem. This can cause your partner to feel insecure. He or she may become possessive or distant.

If problems develop in your relationship, you may benefit from seeing a therapist. Ask your bariatric team for help.

Divorce Change in a relationship can add stress, even if the change is positive. If you are married, you should plan for added stress and how to deal with it.

A therapist or counselor can help you and/your partner work through these changes.

Friend loss Losing a lot of weight can disrupt some friendships. You are changing every day, and you may find that your friends are unwilling or unable to change in the friendship with you. Your friends may be feeling jealous of you or your success.

Body image When your body goes through such a rapid and drastic change, you tend to lose a sense of yourself.

You can actually go through an identity crisis. You may not recognize yourself. You may feel like you are walking around in someone else’s body.

Please remember that it will take some time getting used to the new you. Counseling may help you during these times of uncertainty.

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Source: Allina Health's Patient Education Department, Roux-en-Y Gastric Bypass Surgery: What You Need to Know Before and After Surgery, fourth edition, surg-ahc-90091 (2/10)
Reviewed by: Allina Health's Patient Education Department experts
First Published: 01/25/2005
Last Reviewed: 02/15/2010