Jejunoileal Bypass

The jejunoileal bypass was one of the earliest weight-loss surgeries, developed in the 1950s. It bypassed most of the small intestine so that fewer calories could be absorbed from food. While it produced dramatic weight loss, it caused severe complications and is no longer performed today.

Jejunoileal bypass is a historical malabsorptive bariatric procedure in which the proximal jejunum was anastomosed to the distal ileum, bypassing approximately 90% of the small intestine absorptive surface. Patients lost 30-40% of body weight but suffered severe complications including hepatic failure, nephrolithiasis, electrolyte derangements, bacterial overgrowth, and arthritis-dermatitis syndrome from immune complex deposition. The procedure was abandoned by the 1980s in favour of safer alternatives like Roux-en-Y gastric bypass.

The jejunoileal bypass represents an important chapter in bariatric surgery history — its complications drove the development of today’s much safer procedures like sleeve gastrectomy and gastric bypass. At Accord Medical, Dr Joseph Wang offers evidence-based, modern weight management approaches that prioritise safety and long-term health.