Botanical Name: Smallanthus sonchifolius
The sweet tubers (roots) of this plant are prepared as a snack or used to make syrup. The syrup contains a high amount of fructooligosaccharide, an indigestible fructose complex; thus, yacon has little caloric value.
- Constipation 
- Nonalcoholic Fatty Liver Disease, yacon in combination with milk thistle may be effective 
- Weight Loss in Obese Pre-Menopausal Women with Insulin Resistance 
No Clinical Research:All other conditions.
- Avoid or contact a licensed healthcare practitioner, if you have allergies to plants in the family Asteraceae (ragweed, chamomile, etc.).
- Since there is not enough research on the use of supplements containing yacon, use caution or contact a licensed healthcare practitioner.
There is not enough research on the use of supplements containing yacon during pregnancy and breast-feeding, so consult a licensed healthcare practitioner before use or avoid use. 
Yacon is not a "drug", so the best doses have not been thoroughly established. Make sure to follow the specific product instructions and take as directed on the label, or consult a licensed healthcare practitioner before use.
1. Geyer M, Manrique I, Degen L, Beglinger C. Effect of yacon (Smallanthus sonchifolius) on colonic transit time in healthy volunteers. Digestion. 2008;78(1):30-3. 2. Valentová K, Stejskal D, Bartek J, Dvorácková S, Kren V, Ulrichová J, Simánek V. Maca (Lepidium meyenii) and yacon (Smallanthus sonchifolius) in combination with silymarin as food supplements: in vivo safety assessment. Food Chem Toxicol. 2008 Mar;46(3):1006-13. 3. Genta S, Cabrera W, Habib N, Pons J, Carillo IM, Grau A, Sánchez S. Yacon syrup: beneficial effects on obesity and insulin resistance in humans. Clin Nutr. 2009 Apr;28(2):182-7. 4. Geyer M, Manrique I, Degen L, Beglinger C. Effect of yacon (Smallanthus sonchifolius) on colonic transit time in healthy volunteers. Digestion. 2008;78(1):30-3.
The "-" means there is no information.