The incretin hormones, glucagon-like peptide-1 (GLP-1), and glucose-dependent insulinotropic polypeptide (GIP), play an important role in glucose homeostasis in both health and diabetes. In mice, sucralose, an artificial sweetener, stimulates GLP-1 release via sweet taste receptors on enteroendocrine cells. We studied blood glucose, plasma levels of insulin, GLP-1 and GIP and gastric emptying (by a breath test) in 7 healthy humans after intragastric infusions of (i) 50 g sucrose in water to a total volume of 500 ml (~ 290 mosmol/L), (ii) 80 mg sucralose in 500 ml normal saline (~ 300 mosmol/L, 0.4 mM sucralose), (iii) 800 mg sucralose in 500 ml normal saline (~ 300 mosmol/L, 4 mM sucralose), (iv) 500 ml normal saline (~ 300 mosmol/L), all labelled with 150 mg 13C-acetate. Blood glucose increased only in response to sucrose (P < 0.05). GLP-1, GIP and insulin also increased after sucrose (P = 0.0001), but not after either load of sucralose, or saline. Gastric emptying of sucrose was slower than that of saline (T50: 87.4 ± 4.1 min vs. 74.7 ± 3.2 min, P < 0.005), whereas there were no differences in T50 between sucralose 0.4 mM (73.7 ± 3.1 min), or 4 mM (76.7 ± 3.1 min) and saline. We conclude that sucralose, delivered by intragastric infusion, does not stimulate insulin, GLP-1 or GIP release, or slow gastric emptying in healthy humans.