The actual weight a patient will lose after the procedure is dependent on several factors. These include:
Weight before surgery
Overall condition of patient's health
Ability to exercise
Commitment to maintaining dietary guidelines and other follow-up care
Motivation of patient and cooperation of their family, friends and associates
It is better to be slightly overweight and fit, than to be of normal weight but unfit.
You will be awake after surgery with same weight. After end of first week you will be feeling the process of weight loss. Most of the eight will be lost in initial 6 months and then continues to lose till 18-24 months. With a band, it will be a steady progression of losing 0.5 - 1kg/week once your band is adjusted to the 'sweet spot'.
Resolution of obesity related co-morbidities
If you have diabetes, you have more chance of it resolving completely with operations that achieve a greater weight loss or exclude some of the hormone release in the stomach. High blood pressure and sleep apnoea will almost certainly improve with a lesser degree of weight loss. The length of time and the severity of your obesity–related illnesses will also determine how likely they are to resolve and will be something to discuss with a physician in a multidisciplinary team.
Patients may lose weight upto 18-24 months. Although some patients continues to lose weight, but most of patients finds that weight is stabilized. At this point onward, there are chances of weight gain so patient should be careful in caloric intake and expenditure to prevent weight gain.