Effects of a medical food containing an herbal alpha-glucosidase inhibitor on postprandial glycemia and insulinemia in healthy adults.
OBJECTIVE
To determine the effect of different doses of Salacia oblonga extract, an herbal alpha-glucosidase inhibitor, on postprandial glycemic, insulinemic, and breath hydrogen responses in healthy adults.


METHODS
Double-masked, randomized crossover design.


METHODS
Subjects, after fasting for 12 hours, consumed four test meals consisting of 480 mL of study beverage (14 g fat, 82 g carbohydrate, and 20 g protein) with 0, 500, 700, or 1,000 mg of S oblonga extract on four separate occasions. Capillary finger-prick plasma glucose and venous serum insulin concentrations were measured at baseline and for 2 hours postprandially. Breath hydrogen excretion was measured at baseline and hourly for 8 hours postprandially.


METHODS
Thirty-nine healthy, nondiabetic adults (body mass index=23.7+/-0.4, age=25.7+/-0.9 years.


METHODS
Repeated-measures analysis of variance was applied to the raw data or data that had been transformed (log, rank) when necessary due to nonnormality. The Tukey-Kramer post hoc test was used for pairwise comparisons.


RESULTS
Compared with the control, the 1,000-mg S oblonga extract dose reduced the plasma glucose and serum insulin incremental areas under the curve (0 to 120 minutes postprandial) by 23% ( P =.32) and 29% ( P =.01), respectively. The other doses of S oblonga extract did not impact glycemia or insulinemia. Breath hydrogen excretion increased linearly as the dose of S oblonga extract was advanced.


CONCLUSIONS
The presence of S oblonga extract tended to lower postprandial glycemia and significantly reduced the postprandial insulin response. The increase in breath hydrogen excretion suggests a mechanism similar to prescription alpha-glucosidase inhibitors. Future studies of S oblonga extract in patients with diabetes are needed.
Heacock
Patricia M
PM
Department of Nutritional Sciences, Rutgers, The State University of New Jersey, New Brunswick, USA.
Hertzler
Steven R
SR
Williams
Jennifer A
JA
Wolf
Bryan W
BW
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D019540:Area Under Curve; D001628:Beverages; D001786:Blood Glucose / Q000378:metabolism*; D001944:Breath Tests; D029753:Celastraceae / Q000737:chemistry*; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004791:Enzyme Inhibitors / Q000378:metabolism*; D005260:Female; D005951:Glucose Tolerance Test; D038321:Glycemic Index; D065089:Glycoside Hydrolase Inhibitors; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007328:Insulin / Q000097:blood*; D008297:Male; D010936:Plant Extracts / Q000627:therapeutic use*; D019518:Postprandial Period; D000520:alpha-Glucosidases / Q000378:metabolism
D001786:Blood Glucose; D004791:Enzyme Inhibitors; D065089:Glycoside Hydrolase Inhibitors; D007004:Hypoglycemic Agents; D007328:Insulin; D010936:Plant Extracts; D000520:alpha-Glucosidases