Possible problems after gastric bypass include:

• Constipation. Eating smaller amounts of food can lead to less frequent or more difficult bowel movements.
• Reactive hypoglycemia. If you eat a meal high in carbohydrates, you may develop a blood sugar imbalance, which leads to sweating, lightheadedness and jitters.
• Dumping syndrome. Eating foods high in grease, sugar or fat may cause diarrhea, vomiting, hot flashes and other undesirable symptoms.
• Hibernation syndrome. Because of the decrease in food supply, you may experience depression, lethargy and exhaustion.
• Clogging. Failing to chew food well enough may cause it to become stuck between the food pouch and the intestines, leading to vomiting and discomfort.
• Gas. Gas problems are common after gastric bypass, especially if you consume carbonated products or dairy.
• Vomiting. If you eat too fast or too much or if you fail to chew your food properly, you may vomit.
• Emotional issues. Rapid weight loss can lead to depression, problems in interpersonal relationships, identity crises and cross addiction.

After sleeve gastrectomy, you may experience:

• Vomiting. If you eat too much, eat too fast or swallow food that isn’t chewed properly, you may vomit.
• Clogging. Clogging occurs when you eat too much food at one time or fail to chew properly.
• Constipation. Because your food intake is limited, you may develop constipation, especially if you don’t drink enough liquids or take in enough fiber.
• Gas. You may experience gas after a sleeve gastrectomy. Some foods may be more problematic than others.
• Emotional issues. Losing weight quickly may cause problems in your relationships with others, self-image issues, cross addiction or depression.
• Staple line leakage. Fluids may leak along the staple line, leading to serious complications.

Possible problems you may face after lap band surgery include:

• Constipation. As with other weight loss procedures, you may encounter constipation because of limited food intake.
• Vomiting. Eating too much, insufficient chewing or eating too fast can lead to nausea and vomiting.
• Clogging. Food can become stuck in the band, if the patient eats fast or not chew the food well.
• Gas. Some patients experience gas and bloating after lap band surgery.
• Emotional issues. As you lose weight, you may struggle with self image, depression, addictive behaviors and other emotional problems.