Reflux, diabetes, BMI, eating pattern and willingness to supplement for life — those five answers point to one operation.
Significant existing reflux usually points to bypass, because a sleeve can worsen it. A sleeve in a patient with severe GERD is the commonest reason for later conversion surgery.
Bypass produces higher remission rates and faster glycaemic improvement because of hormonal changes in the rerouted gut. With diabetes plus obesity, bypass is often the stronger recommendation.
Very high BMI and 'sweet eater' patterns tend to do better with bypass. Volume eaters without reflux do very well with a sleeve, which is simpler and preserves normal absorption.
Bypass requires lifelong B12, iron, calcium and vitamin D with annual bloods. If you know you will not take them, the sleeve is the safer operation for you — an honest answer here prevents anaemia years later.
Yes, and it is a recognised second-stage operation, most often for reflux or insufficient weight loss.