How Effective is Surgery? | Boston Medical Center
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How Effective is Surgery?

The actual weight a patient will lose after the procedure is dependent on several factors. These include:

  • Patient's age
  • Weight before surgery
  • Overall condition of patient's health
  • Surgical procedure
  • Ability to exercise
  • Commitment to maintaining dietary guidelines and other follow-up care
  • Motivation of patient and cooperation of their family, friends and associates

In general, weight loss surgery success is defined as achieving loss of 50% or more of excess body weight and maintaining that level for at least five years.

Clinical studies show that, following gastric bypass surgery, most patients lose weight rapidly and continue to do so until 18 to 24 months after the procedure.

  • After Gastric Bypass, patients may lose 30 to 50% of their excess weight in the first six months and 68% of excess weight as early as 12 months after surgery.
  • Long term studies show that patients can maintain a 50-60% loss of excess weight 10-14 years after surgery.
  • Patients with higher initial BMIs, greater than 60, tend to lose more total weight. Patients with lower initial BMIs, 40 to 45, will lose a greater percentage of their excess weight and will more likely come closer to their ideal body weight.
  • Patients with Type 2 Diabetes tend to show less overall excess weight loss than patients without Type 2 Diabetes, but in these patients, improvement and resolution of diabetes is our primary concern.