Freeze-dried powdered yacon: effects of FOS on serum glucose, lipids and intestinal transit in the elderly

Eur J Nutr. 2014 Oct;53(7):1457-64. doi: 10.1007/s00394-013-0648-x. Epub 2014 Jan 8.


Background and aims: Freeze-dried powdered yacon (FDY) can be considered a prebiotic product due to its fructooligosaccharides (FOS) content. The effect of 9 weeks of daily intake of FDY containing 7.4 g of FOS on glucose, lipid metabolism and intestinal transit in a group of elderly people was investigated.

Methods: Seventy-two elderly (mean age 67.11 ± 6.11) men and women were studied for 9 weeks in a double-blind, placebo-controlled experiment. They were randomly assigned to the supplement group (which received 7.4 g of FOS as FDY) or the control group. At the beginning and end of the study, anthropometric measurements, blood sampling, clinical analyses and dietary intake were assessed.

Results: A daily intake of FDY containing 7.4 g of FOS for 9 weeks was associated with a mean decrease in serum glucose (p = 0.013), but supplementation did not reduce serum lipids in the study group. The administered dose did not adversely affect intestinal transit. It did not cause bloating, flatulence or intestinal discomfort.

Conclusion: Freeze-dried powdered yacon is a good source of FOS, and daily consumption can have a favourable effect on serum glucose in the elderly. It is also practical, easy and safe to use and store.

Publication types

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

MeSH terms

  • Aged
  • Blood Glucose / metabolism*
  • Body Mass Index
  • C-Reactive Protein / metabolism
  • Cholesterol, HDL / blood
  • Cholesterol, LDL / blood
  • Dietary Supplements*
  • Double-Blind Method
  • Female
  • Freeze Drying
  • Humans
  • Intestinal Mucosa / metabolism
  • Intestines / drug effects*
  • Lipid Metabolism / drug effects
  • Male
  • Middle Aged
  • Oligosaccharides / administration & dosage*
  • Oligosaccharides / chemistry
  • Prebiotics*
  • Triglycerides / blood
  • Waist Circumference


  • Blood Glucose
  • Cholesterol, HDL
  • Cholesterol, LDL
  • Oligosaccharides
  • Prebiotics
  • Triglycerides
  • fructooligosaccharide
  • C-Reactive Protein