Here it is, couldn't find his original post but this is the bit about dumping:
Roux-en-Y Gastric Bypass and Dumping Syndrome
Dumping syndrome is a common side effect after Roux-en-Y Gastric Bypass (RNYGB) surgery. About 85% of gastric bypass patients will experience dumping syndrome at some point after surgery. The symptoms can range from mild to severe.
Dumping usually occurs due to poor food choices. It is related to the ingestion of refined sugars (including high fructose corn syrup) or high glycemic carbohydrates. It can also occur with dairy products, some fats, and fried foods. These foods rapidly empty from the gastric pouch into the small intestine which triggers a cascade of physiologic events.
The effect of dumping is twofold. It is both good and bad. The benefit is that if dumping occurs after eating these foods the patient is less likely to eat that food again. It is a built in mechanism that says, “I shouldn’t have eaten it the first time, and I definitely won’t eat it again.” This is called negative reinforcement. The fact is these foods will interfere with long-term weight loss and should not be eaten anyway.
The bad news is that dumping makes you feel awful; it can be confused with other problems; it is scary and sometimes difficult to manage; and it may have some short-term physiologic consequences.
There are two types of dumping:
1. Early dumping which occurs 30-60 minutes after eating and can last up to 60 minutes. Symptoms include sweating, flushing, light headedness, tachycardia, palpitations, desire to lie down, upper abdominal fullness, nausea, diarrhea, cramping, and active audible bowels sounds.
2. Late dumping which occurs 1-3 hours after eating. Symptoms are related to reactive hypoglycemia (low blood sugar) which include sweating, shakiness, loss of concentration, hunger, and fainting or passing out.
Early dumping occurs as a result of rapid emptying of sugars or carbohydrates from the gastric pouch into the small intestine which causes the release of hormones (gut peptides) that effect blood pressure, heart rate, skin flushing and intestinal transit, leading to a light-headed, rapid heart rate and flushing sensation often accompanied by diarrhea. Late dumping symptoms are related to increased insulin after oral glucose (sugar) with subsequent hypoglycemia (low blood sugar).
The diagnosis of dumping syndrome is primarily made by obtaining a history of the presence of classic symptoms related to food intake. Management of early dumping can be relatively straightforward. First, the symptoms should be discussed with the Bariatric Surgeon. Dietary compliance with avoidance of refined sugars, high glycemic carbohydrates, or other foods that may be associated with the syndrome would be the primary treatment.
Management of late dumping that persists in spite of the above dietary measures may be treated with a small amount of sugar (such as one-half glass of orange juice) about one hour after a meal, which may prevent the attack. Medications such as Acarbose or Somatostatin may be helpful if still symptomatic despite dietary changes. -. One should consider the rare possibility of insulinoma or neisidioblastosis of the pancreas if late dumping remains refractory to medical management.
In summary, although bothersome and sometimes worrisome, dumping syndrome is not a life-threatening problem. Repetitive patient education about what to eat and what not to eat can manage early and late dumping syndrome. Also patients need to learn about and read basic nutrition labels. The benefit is that it teaches patients quickly that certain foods and additives cannot be tolerated. Patient compliance and commitment to long-term follow-up are mandatory.