A cross-sectional observational study in which pouch emptying rate is measured with MRI in good (TWL>35%) and bad responders (TWL<25%) two years after Laparoscopic Roux-en-Y Gastric Bypass (LRYGB).

Inclusion Criteria:

• Women aged between 20 and 55 years
• Patients must be able to adhere to the study visit schedule and protocol requirements
• Patients must be able to give informed consent (IC) prior to any study procedures
• Patients who had a follow-up period up until two years after LRYGB and have successful or unsuccessful weight loss.
• Willing to be informed about incidental findings of pathology and approving of reporting this to their general physician

Exclusion Criteria:

• Diabetes Mellitus

• Menopausal

• Gastrointestinal problems, gastric or intestinal diseases

• Drug or alcohol addiction

• Inability to stop smoking during the overnight fasting period

• Pregnant or lactating

• Having an intolerance or allergy for one of the components of the test product

• Inability to stop medications that affect gastrointestinal emptying like antisecretory drugs, narcotics and prokinetic agents

• Inability to stop medication that affects the motility of the upper gastrointestinal tract (anti-cholinergic drugs, prokinetics, theophylline, calcium blocking agents, opioids)

• Having a contra-indication to MRI scanning (including, but not limited to):

  • Pacemakers and defibrillators
  • Intraorbital or intraocular metallic fragments
  • Ferromagnetic implants

RYGB, with succesful (>35%) or unsuccesful (<25%) weight loss