Effect of an Arabinogalactan Product

Dietary fiber is an important nutrient that supports gastrointestinal function as well as blood glucose and cholesterol maintenance. The National Academy of Sciences Institute of Medicine (IOM) established an adequate intake for fiber as 14 g/kcal, or 38 g and 25 g for men and women, respectively. Currently, however, the majority of the U.S. population falls substantially below this level, with mean intakes of 18.9 g/day and 15.7 g/day in men and women age 20 and older, respectively. Fiber is a complex category that contains a number of different polysaccharides and oligosaccharides that are not digested in the upper gastrointestinal tract. In its final rule updating the Nutrition and Supplement Facts label regulations, which was published in May 2016, the U.S. FDA revised the definition of dietary fiber for food labeling and included two categories: (1) the intrinsic and intact non-digestible carbohydrate (NDC) and lignin, and (2) the isolated or synthesized NDC. In this re-definition, those NDCs that are isolated from plant and other food sources will now require clinical data indicating that the ingredient provides a physiological effect that is beneficial to human health. This study is designed to test the effect of an isolated NDC, arabinogalactan, on attenuation of blood glucose and/or insulin. Attenuation of blood glucose and/or insulin is one of the outcomes identified by the U.S. FDA as a physiological effect that is beneficial to human health, and as such, can be used to support that an isolated NDC is acting as a fiber (FDA 2018). Arabinogalactans are hemicelluloses that are abundant in plants. Arabinogalactans are found in seeds, leaves, roots, and fruit of higher plants, such as cereals, beans, leeks, pear, corn, and wheat (Saeed 2011; Dion 2016). The arabinogalactan ingredient used in the study is isolated from larch (Larix laricina) using a patented water-based extraction process. Larch arabinogalactan has been designated as Generally Recognized as Safe (GRAS) by the U.S. FDA (2000) for multiple uses and has been used in numerous previous clinical studies in humans, with no significant safety issues observed at intakes of up to 30 g daily for up to 6 weeks. The present study was designed with the goal to assess the effect of acute consumption of arabinogalactan on blood glucose and insulin responses.