Yacon syrup reduces postprandial glycemic response to breakfast: A randomized, crossover, double-blind clinical trial

Food Res Int. 2019 Dec;126:108682. doi: 10.1016/j.foodres.2019.108682. Epub 2019 Sep 15.


Yacon is a root rich in fructooligosaccharides (FOS), which act as prebiotics. Numerous studies have shown promising results in the technological aspects of producing yacon syrup. However, uncertainties exist concerning whether yacon syrup can modulate postprandial glucose and lipid profiles. In order to assess the effect of yacon syrup on postprandial glucose, insulin and triglyceride (TG) responses, a randomized, crossover, double-blind clinical intervention with 40 women (20 normal weight and 20 grade I obese) was performed. Participants underwent two-arms of intervention with at least a one-week wash-out period between visits. On each intervention day, after 12 h of fasting, an aliquot of blood was collected. For intervention A, volunteers consumed breakfast +40 g of placebo, whereas for intervention B, participants consumed breakfast +40 g of yacon syrup (14 g of FOS). Blood samples were drawn at 15, 30, 45, 60, 90, and 120 min. Glucose and insulin concentrations were lowered after yacon syrup intake as compared to placebo at following times: 30 min for glucose and 15, 30 and 45 min for insulin. In conclusion, yacon syrup has a postprandial decreasing effect glucose and insulin concentrations in adult women. This effect was not evident for triglyceride concentration. Clinical trial registry: RBR-33wf46. Available in: http://www.ensaiosclinicos.gov.br/rg/RBR-33wf46/.

Keywords: Fructooligosaccharides; Postprandial period; Prebiotics; Smallanthus sonchifolius; Women.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Blood Glucose / drug effects*
  • Breakfast / physiology*
  • Cross-Over Studies
  • Double-Blind Method
  • Female
  • Humans
  • Insulin / blood
  • Oligosaccharides
  • Plant Extracts / pharmacology*
  • Postprandial Period / drug effects*
  • Prebiotics
  • Young Adult


  • Blood Glucose
  • Insulin
  • Oligosaccharides
  • Plant Extracts
  • Prebiotics
  • fructooligosaccharide
  • yacon syrup