Emptying of the gastric substitute and small bowel transit time of a 99mTc-labeled solid test meal were measured in 20 tumor-free patients 13 to 63 (median, 35) months after total gastrectomy with Roux-y (n = 11) and jejunal interposition (n = 9) reconstruction. The emptying half-times ranged from 2 minutes to greater than 20 minutes. Rapid emptying was associated with dumping symptoms (p less than 0.03) and shorter orocoecal transit-time (p less than 0.05). Serum glucose concentrations rose more quickly in jejunal interposition, but the areas under the curve were identical in both groups. The median insulin-to-glucose ratio (areas under the curve) during the 20 minutes after the meal was 11.4 in jejunal interposition and 7.1 in Roux-y esophagojejunostomy (NS). Interposition cases had regained a significantly higher percentage (89%) of their premorbid weight than patients with Roux-y (78%; p less than 0.05). The weight/height2 ratio was above the 50th centile in 45% of interpositions, but below the 50th centile in all patients after the Roux-y mode of reconstruction (p less than 0.05). It is concluded that the emptying velocity of the gastric substitute has no impact on postoperative weight gain. The authors contend that the concept of a gastric substitute pouch is not supported by the findings of this study.