Hope,
The side effects that Shelbell is referring to are from a bypass, not a sleeve (Shelbell's info and stats and type of surgery are displayed down the left hand side).
The most likely long term side effects I have been told about from a sleeve are acid reflux (which can be controlled with meds), possible ulcers (but this can also happen with RNY bypass), possibly slightly less likely to reach goal weight (but this is an estimation -- many doctors keep "saying" the RNY leads to greater weight loss, but the most recent stats suggest very similar weight loss outcomes at 2 years from both ops).
The most likely long term side effects from a bypass are: malnutrition / malabsorption (for which over-correction -- eating higher quantities of protein and vitamin supplements is required, as Shelbell does) .... and possibly twisted bowels (because with the RNY the remaining stomach and upper intestinal tract is left floating, slightly lose, now disjoined from the new pouch -- whereas with the sleeve, the excess stomach is removed and the remaining intestinal tract remains as it was, unaltered).
The malnutrition can in a few EXTREME cases be so severe that the patient cannot keep food down and requires hospitalisation. (Unfortunately I have met 2 post RNY bypass patients who have had this level of malnutrition, and even if they are unusual, it is not something I want to go thru myself -- one of them spent 9 months in hospital being tube fed and is still now seriously underweight. I would rather take the risk with the sleeve of ending up a few stones overweight, but "healthy" than seriously malnourished and underweight and fighting to keep food down.)
None of these complications happen to EVERYONE, only a small percentage of patients run into complications for either operation.