Yacon has been recognised as an exciting food with great potential. Its main unique property is that the Yacon plant stores its energy in the form of FOS (fructo-oligosaccharide). This completly natural sugar is showing more and more promise for good health. Most of the processed foods today contain mostly simple carbohydrates that spike blood glucose levels and can lead to conditions like obesity and diabetes. Humans do not contain the enzyme to digest FOS so it travels through the digestive system relatively unchanged. When it reaches the large intestine, the FOS is used by the probiotic bacteria which contribute greatly to digestive and overall health. Some of the published scientific studies are shown below.

Yacon syrup is naturally low in calories. Generally, the caloric content of carbohydrates is about 4 kcal/g. FOS, being a special type of carbohydrate, has a caloric content of between 1 and 1.5 kcal/g (Roberfroid, 1999). The caloric content of yacon syrup is approximately 2.5 kcal/g due to the simple carbohydrates also present.

Yacon syrup can promote better health of the gastrointestinal tract. Yacon fructooligosaccharide (FOS) are completely fermented in the colon by probiotics (Pedreschi et al., 2003), a group of beneficial bacteria that forms part of the intestinal microflora. The bifidogenic effect of FOS has been well proven (Bouhnik et al., 1996; Gibson et al., 1995; Gibson and Roberfroid,1995; Hidaka et al., 1986). These bacteria (especially some species of the genus Bifidus and Lactobacillus) contribute to better gastrointestinal function and help to alleviate several digestive disorders. Health benefits ascribed to Bifidobacteria include the following: inhibiting the growth of harmful bacteria, stimulating components of the immune system, improved uptake of calcium and other minerals, improved mineralization of bone, regulation of cholesterol levels, reduced constipation, diminished risk of developing colon cancer, synthesis of B-vitamins, and inhibition of the production of toxins and other carcinogenic substances in the colon (Chen et al., 2000; Scholz-Ahrens et al., 2001; Abrams et al., 2005; Liong & Shah, 2005; Pool-Zobel, 2005; Tuohy et al., 2005). In addition, recent research has found that infant formula containing a mixture of GOS (Galactooligosaccharide) and FOS resulted in stimulating the typical microbial ecology of breast-fed infants (Bakker-Zierikzee et al., 2005). Much of this research requires further investigation and extensive clinical trials to prove the effects of FOS on human health. However, the research accumulated shows the likely benefits of FOS intake.

Yacon Syrup has little effect on blood glucose levels. Tests were conducted at the Universidad Nacional Mayor de San Marcos in Peru in July 2004 to test how Yacon syrup affected blood glucose levels. 60 non-diabetic men and women aged between 20 and 60 fasted for at least eight hours before ingesting different sweeteners. The sweeteners tested were Yacon syrup, honey, maple syrup, and anhydrous glucose. The group ingesting Yacon syrup had hardly any fluctuation in blood glucose levels while the other sweeteners showed an immediate significant rise and a slow decline back to normal. The results showed that Yacon syrup has very little effect on glucose levels and can be suitable for moderate use by diabetics.

FOS behaves as soluble fibre which causes several favourable effects during digestion. These include an increase of intestinal peristaltic movements, a reduction in time of intestinal transit, and an increase in the amount of water retained by the faecal matter. Therefore, yacon syrup can help maintain regular bowel movements and prevent constipation (Chen et al., 2000).

References
Abrams, S., Griffin, I., Hawthorne, K., Liang, L., Gunn, S., Darlington, G. Ellis, K. (2005). A combination of prebiotic short- and long-chain inulin-type fructans enhances calcium absorption and bone mineralization in young adolescent. The American Journal of Nutrition. 82: 471-476.

Bakker-Zierikzee, A.M., Alles, M.S., Knol, J., Kok, F.J., Tolboom, J.M., Bindels, J.G. (2005) Effects of infant formula containing a mixture of galacto- and fructo-oligosaccharides or viable Bifidobacterium animalis on the intestinal microflora during the first 4 months of life. British Journal of Nutrition. 94: 783-790.

Bouhnik, Y., Flourie, B., Riottot, M., Bisetti, N., Gailing, M.F., Guibert, A., Bornet, F., Rambaud, J.C. (1996) Effects of fructo-oligosaccharides ingestion on fecal bifidobacteria and selected metabolic indexes of colon carcinogenesis in healthy humans. Nutrition and Cancer. 26(1): 21-29.

Chen, H., Yu-Ho, L., Jiun-Jr, L., Lie-Yon, K. (2000). Effects of fructooligosaccharide on bowel function land indicators of nutritional status in constipated elderly men. Nutrition Research. 20: 1725-1733.

Gibson, G.R., Beatty, E.R., Wang, X., Cummings, J.H. (1995) Selective stimulation of bifidobacteria in the human colon by oligofructose and inulin. Gastroenterology. 108: 975-982.

Gibson, G.R. & Roberfroid, M.B. (1995) Dietary modulation of the human colonic microbiota: introducing the concept of prebiotics. The Journal of Nutrition. 125: 1401-1412.

Hidaka, H., Eida, T., Takizawa, T., Tokunaga, T., Tashiro, Y. (1986) Effects of fructo-oligosaccharides on intestinal flora and human health. Bifidobacteria Microflora. 5: 37-50.

Liong, M., Shah, N. (2005). Optimization of cholesterol removal, growth and fermentation patterns of Lactobacillus acidophilus ATCC 4962 in the presence of mannitol, fructo-oligosaccharide and inulin: a response surface methodology approach. Journal of Applied Microbiology. 98: 115-1126.

Pedreschi, R., Campos, D., Noratto, G., Chirinos, R., Cisneros-Zevallos, L. (2003). Andean yacon root (Smallanthus snchifolius Poepp. Endl) fructooligosaccharides as a potential novel source of prebiotics. Journal of Agricultural and Food Chemistry. 51(18): 5278-5284.
Pool-Zobel, B. (2005). Inulin-type fructans and reduction in colon cancer risk: review of experimental and human data. British Journal of Nutrition. 93: S73-S90.

Scholz-Ahrens, K.E., Schaafsma, G., Van den Heuvel, E., Schrezenmeir, J. (2001) Effects of prebiotics on mineral metabolism. The American Journal of Clinical Nutrition. 73: 459S-464S.
Tuohy, K., Rouzaud, G., Bruck, W., Gibson, G. (2005). Modulation of the human gut microflora towards improved health using prebiotics—assessment of efficacy. Curr Pharm Des. 11: 75-90.