Verifying Fibers Meet Regulatory Definitions for Nutrition Facts labeling: A Randomized, Controlled Trial Evaluating Polydextrose in a Wet Matrix

Abstract

BACKGROUNDFibers have many health benefits, but most Americans only meet half their recommended daily fiber intake. This ‘fiber gap’ has prompted the food industry to add functional fibers in typically low fiber food items. However, the FDA has now proposed a rule for the Nutrition Facts label that added fibers must demonstrate a physiological health benefit to be included in the label as a dietary fiber. Polydextrose is a non‐digestible carbohydrate with inconsistent findings on its glycemic health effect. Therefore, the objective of this study was to assess the effect of adding polydextrose to a liquid (wet matrix) food product on postprandial glycemia.METHODSIn this randomized, singe‐blind, 4‐arm, crossover trial, 34 healthy men and women with a mean (±SD) age of 30.6 ± 8.17 y were asked to consume a sugar beverage with 50 g dextrose and 0, 8, 12, or 16 g of added polydextrose alongside a light breakfast of toast with butter. Blood samples were collected before beverage consumption and 30, 60, 120 and 180 min after consumption for evaluation of plasma glucose and insulin levels. Gastrointestinal (GI) tolerability was evaluated with a tolerability questionnaire 4 days after clinic visit.RESULTSSignificant treatment and time effects were observed for glucose with the addition of polydextrose (p=0.01 and p<0.0001, respectively). Addition of 12 g polydextrose lead to a significant increase in post prandial glucose by 5.83 mg/dl compared to 0 g control (p=0.005). Postprandial insulin tended to be higher with the same polydextrose dose compared to control (p=0.0680). Total area under the curve (AUC) was also significantly higher with 12 g addition of polydextrose compared to control for post prandial glucose and insulin (p=0.0367 and p=0.0263, respectively). Polydextrose was well tolerated at all dosages investigated based on GI tolerability scores.CONCLUSIONPolydextrose did not lower postprandial glucose in a wet matrix as tested across a dose range of 0–16 g. Increased postprandial glucose and insulin responses were indicated at the 12 g dose. Based on glycemic effect as seen in this study's results, polydextrose cannot yet be considered as a dietary fiber on the Nutrition Facts label. However, considerations into different matrices and alternative fiber benefits should be considered for a full evaluation of potential fiber benefits offered by polydextrose.Support or Funding InformationIIT/FDA Corporate Agreement