The Effects of Bariatric Surgeries on Glucose Metabolism


  • Diabetes, obesity and weight loss surgery

Study Name

The Effects of Bariatric Surgeries on Glucose Metabolism (IRB no. 42886)


The purpose of this study is to examine changes in glucose metabolism after weight loss surgery. Insulin is the main hormone that controls the level of glucose (sugar) in the blood. The two most commonly performed weight loss surgeries, gastric bypass surgery and sleeve gastrectomy, improve glucose control in patients with Type 2 diabetes before any weight loss occurs.

Participants in this study have undergone weight loss surgery or are healthy volunteers who have not had gut surgery (control subjects). Researchers will determine the effects of bariatric surgery on blood glucose levels and insulin response that are mediated by gut hormones and neural activity. They will also compare patients with symptoms of low sugar (sweating, fast heartbeat, impaired cognition, loss of consciousness, seizure, etc.) after weight loss surgery to those without symptoms in order to determine the cause of hypoglycemia (low sugar) after surgery. The study may use may use synthetic (man-made) forms of the gut hormones GLP-1 and GIP, as well as a compound that blocks the effect of GLP-1; all three drugs are investigational.


Key Inclusion Criteria:

  • Subjects who have had or will have bariatric surgery (hypoglycemic or non-hypoglycemic) and non-surgical controls
  • 18-65 years old

Key Exclusion Criteria:

  • Pregnancy
  • Hemoglobin <11 (unless being studied for screening meal tolerance test)
  • Current gastrointestinal obstruction
  • Diagnosed with diabetes mellitus

Please see additional list of inclusion and exclusion criteria.

Principal Investigator

Marzieh Salehi, MD, MS, FACP


Rashin Sedighi, PhD, MS, RN
Phone: 310-423-3533