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The effect of three snack bars on glycemic response in healthy adults
Carla K Miller1, Robert A Gabbay, Judith Dillon
1Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA 16802, USA. ckm105@psu.edu
Abstract:
Many consumers prefer convenient, portable, and preportioned snack foods. Foods with a lower glycemic response are associated with reduced risk for chronic disease. The glycemic index and glycemic load of three nationally available snack bars were determined. Ten subjects, with mean age (+/-standard deviation) of 29+/-7 years and mean body mass index (+/-standard deviation) of 25.3+/-3.2, were tested on four occasions on nonconsecutive days. After an overnight fast, subjects consumed 50 g of available carbohydrate as a glucose beverage or as a portion of one of three bars: SmartZone nutrition bar (The Hershey Co, Hershey, PA), ZonePerfect nutrition bar (Abbott Laboratories, Abbott Park, IL), or SlimFast meal bar (SlimFast Foods Co, West Palm Beach, FL). Blood glucose was tested at 0, 15, 30, 45, 60, 90, and 120 minutes after consumption. Incremental area under the glucose response curve was calculated for each test bar and compared with that of the glucose beverage to determine glycemic index. The glycemic index (+/-standard error of the mean) for SmartZone was 10.9+/-3.9 and was significantly less (P<0.05) than that of ZonePerfect (43.7+/-7.3) or SlimFast (63.8+/-13.0). The glycemic loads (+/-standard error of the mean) for the SmartZone (2.0+/-0.7) and ZonePerfect (8.3+/-1.4) bars were significantly less (P<0.05) than the glycemic load of the SlimFast bar (21.1+/-4.3). Although the long-term impact of snack foods with a lower glycemic load requires further research, the SmartZone and ZonePerfect bars provide a lower glycemic response for consumers.
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