title: A dose-response evaluation of freeze-dried strawberries independent of fiber content on metabolic indices in abdominally obese individuals with insulin resistance in a randomized, single-blinded, diet-controlled crossover trial.
abstract: This study evaluated the dose-response relationship of strawberries, an anthocyanin-rich fruit, on postprandial glucose and insulin concentrations in individuals with insulin resistance (IR), including changes in plasma anthocyanins, markers of oxidative stress, and inflammation.
  
  
  
  In a randomized controlled, four-arm, dose-response, crossover trial, 21 adults with IR consumed a high-carbohydrate, high-fat meal with one of four beverages containing 0 g freeze-dried whole strawberry powder (0g FDS, control), 10, 20, or 40 g FDS, controlled for fiber. Blood was collected at 0 min and at 30 min intervals postmeal until 2 h, then hourly until 6 h. Postmeal insulin concentrations (6 h) were significantly reduced after the 40-g FDS beverage compared to other beverages (p < 0.05). Postmeal 6 h glucose concentrations were not different, although mean insulin:glucose ratio was significantly different among beverages (p < 0.05). Pelargonidin-glucuronide was inversely associated with mean insulin concentrations after the 20 and 40 g FDS (p < 0.05). Oxidized low-density lipoprotein was reduced after 20 g FDS (p < 0.05) and IL-6 was not different among treatments. Strawberry intake reduced the insulin demand to manage postmeal glucose in obese individuals with IR, which was related to plasma anthocyanin/pelargonidin concentrations.
  
  
  
  The data support a role of strawberries in improving insulin sensitivity in people with IR.
authors: Center for Nutrition Research, Institute for Food Safety and Health, Illinois Institute of Technology, Chicago, IL, USA.
authors: Eunyoung
authors: E
authors: Park
authors: Center for Nutrition Research, Institute for Food Safety and Health, Illinois Institute of Technology, Chicago, IL, USA.
authors: Indika
authors: I
authors: Edirisinghe
authors: Center for Nutrition Research, Institute for Food Safety and Health, Illinois Institute of Technology, Chicago, IL, USA.
authors: Hequn
authors: H
authors: Wei
authors: Center for Nutrition Research, Institute for Food Safety and Health, Illinois Institute of Technology, Chicago, IL, USA.
authors: Lakshmi Prabha
authors: LP
authors: Vijayakumar
authors: Center for Nutrition Research, Institute for Food Safety and Health, Illinois Institute of Technology, Chicago, IL, USA.
authors: Katarzyna
authors: K
authors: Banaszewski
authors: Center for Nutrition Research, Institute for Food Safety and Health, Illinois Institute of Technology, Chicago, IL, USA.
authors: Jack C
authors: JC
authors: Cappozzo
authors: Center for Nutrition Research, Institute for Food Safety and Health, Illinois Institute of Technology, Chicago, IL, USA.|Department of Nutrition, University of California, Davis, CA, USA.
authors: Britt
authors: B
authors: Burton-Freeman
mesh_terms: D000328:Adult; D000872:Anthocyanins / Q000097:blood; D001628:Beverages / Q000032:analysis; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D018592:Cross-Over Studies; D004032:Diet; D004043:Dietary Fiber / Q000008:administration & dosage* / Q000032:analysis; D005260:Female; D031985:Fragaria / Q000737:chemistry*; D005612:Freeze Drying; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D015850:Interleukin-6 / Q000097:blood; D008077:Lipoproteins, LDL / Q000097:blood; D008297:Male; D062407:Meals; D008875:Middle Aged; D056128:Obesity, Abdominal / Q000178:diet therapy*; D018384:Oxidative Stress; D019518:Postprandial Period; D016037:Single-Blind Method
chemical_list: D000872:Anthocyanins; D015415:Biomarkers; D001786:Blood Glucose; D004043:Dietary Fiber; C508600:IL6 protein, human; D007328:Insulin; D015850:Interleukin-6; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein; C066957:pelargonidin