In this study, researchers measured weight within the 30-day period prior to surgery, 6 months after surgery, and annually.

https://www.endocrinologyadvisor.com/obesity/roux-en-y-gastric-bypass-outcome-diabetes-surgery-satisfaction/article/811016/

Related weight regain study:

https://www.ecnmag.com/article/2018/10/amount-weight-regain-after-bariatric-surgery-helps-predict-health-risks

Edited October 30, 20187 yr by Missouri-Lee's Summit

Very interesting ! So the most realistic view based on this study is now that patients can hope to successfully maintain on average ~75% of maximum weight lost...

Edited October 30, 20187 yr by GreenTealael

And saw another study which states 20-30% of all RnY Bypassers have significant weight regain, want to go back and re-scan, want to see what they attribute it to. Is it faulty eating, lack of commitment or something more occult? Scarey-Beary, I came into this hoping to lose weight and then keep it off!???

19 minutes ago, Frustr8 said:

Scarey-Beary, I came into this hoping to lose weight and then keep it off!???

WLS is still your best chance to get rid of the weight and keep the weight off. However, in the end WLS is like any other medical/surgical therapy: there is no 100% success rate.