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Side Effects of Bariatric Surgery

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Because so much weight is lost in a short period, side effects can develop.  These side effects are also seen in people who've lost weight without surgery.

  1. Transient Hair Loss
    Almost every gastric bypass and BPD patient suffers hair loss and hair thinning during the first six months. Hair loss is alarming, however it will not lead to baldness and it is reversible. Once your weight stabilizes and you consume more protein, the hair will grow back.

  2. Nausea/Dumping Syndrome
    Since your new stomach pouch is quite small, you will not be able to eat as much food as you once did.  If you get full and continue to eat, or eat quickly without chewing you will get pain and start to vomit.  You will soon learn how to avoid this. Overeating or consuming concentrated sweets or carbohydrates can lead to nausea and dumping syndrome; food constituents are quickly absorbed from the small intestine leading to profuse sweating, nausea, dizziness, palpitations and weakness.

  3. Nutritional deficiencies
    These are particularly common in patients who have undergone a gastric bypass or BPD/DS, which causes food to skip the duodenum (the section of the small intestine where most iron and calcium are absorbed). Left uncorrected, this can lead to anemia or osteoporosis.  Patients with a biliopancreatic diversion, which by design dramatically reduces nutrient absorption, have to take even greater care to avoid nutritional deficiencies. The good news is these problems can be avoided by eating the right foods in small amounts, taking regular vitamin and mineral supplements, and getting regular medical checkups.

  4. Lactose Intolerance
    After bariatric surgery, lactase (enzyme needed to digest milk and other dairy products) does not reach food in the usual fashion.  Consequently, you may become lactose intolerant leading to wind, abdominal cramping and diarrhea. This can be resolved by avoiding dairy products and switching to alternatives like soya.

  5. Changed Bowel Habits
    Weight loss surgery changes your digestion as well as your food intake. Some patients experience constipation which can be treated with a mild natural stool softener or by simply increasing drinking more fluids. After a biliopancreatic diversion (BPD)/duodenal switch (DS), patients may experience diarrhea. This is usually caused by having too much fat in the diet. If not, a small amount of pancreatic enzymes may be required, which would be prescribed by your surgeon.

  6. Loss of Muscle Mass
    You may lose muscle mass after surgery. Since you're consuming far fewer calories and less protein, your body will look to burn other energy stores to maintain itself.  Surprisingly, the body prefers to use protein-rich muscle for energy before it taps into fat.  Therefore, your initial weight loss may come at the expense of muscle.  This is most common after a gastric bypass or BPD/DS.  Fortunately, this can be avoided by exercising every day and consuming more protein.   Regular aerobic activity and weightlifting is highly recommended. These activities can be alternated, but should be done at least 3 times a week for 20 to 30 minutes at a time. Daily exercise is ideal and should be the goal.  Regular exercise increases fat burning, builds and tones muscle, and raises your energy level, leading to a more fulfilling life.

  7. Gallstones
    With any rapid weight-loss, there is an increased risk of developing gallstones. About one in ten people who undergo bariatric surgery will need to have their gallbladders removed.

  8. Excess Skin
    After losing a large amount of weight, you may find yourself with excess skin in all sorts of places.  This can be removed with plastic surgery.  It's advisable to wait 18 to 24 months, after you lose most of your excess weight and your body begins to equilibrate.  Should plastic surgery be necessary, be sure to choose a surgeon with experience in this area. 

  9. Pregnancy Problems
    Little is known about pregnancy after weight-loss surgery. Although women have successfully carried pregnancies to term as early as six months after bariatric surgery, their babies have all tended to be underweight. Other patients have had miscarriages if they became pregnant shortly after surgery. Because of these uncertainties, we suggest that you wait for at least 18 months after surgery to have a child. And even after that, make sure that your obstetrician is aware of that you've had weight-loss surgery.  You and your baby should be followed closely.

    If you have a Lap-band, you may need to have a band adjustment, allowing you to take in enough nutrition during pregnancy. After delivery, the band can be tightened accordingly.

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