Surgery To Loose Weight Can You Do The Gastric Bypass Diet And Loose Weight Without Doing The Surgery? If I Eat Tiny Portions/vitamin

Can you do the gastric bypass diet and loose weight without doing the surgery? If I eat tiny portions/vitamin - surgery to loose weight

I would like, based on the worst way to lose, but we have lost over 100 pounds and can not benefit from surgery - not what I want. What happens if I eat smaller portions?