Guar gum is a common food additive that is extracted from guar beans; it can help stabilize food and animal feed, and is also used as a thickener. New research has suggested that not all fibers have the same impact on the body, and that guar gum provides a fiber that can reduce inflammation and delay the onset of some symptoms of multiple sclerosis (MS). The research, which used a mouse model and still has to be confirmed in humans, has been published in Cell Reports.
In this study, the researchers gave several different diets to various groups of mice that all are disease models of MS. One group received a normal diet with 5 percent cellulose; another group got a diet that did not contain any dietary fiber at all, and other groups ate a diet containing 30 percent fiber that was either from inulin, pectin, resistant starch, or guar gum. Out of all of the diets that were tested, only the diet high in guar gum relieved symptoms of MS in this model.
The researchers determined that once the guar gum is taken in, gut microbes in the mice start to break it down, creating molecules that seem to lower the activity and proliferation of a type of immune cell known as CD4+ T cells, Th1 cells. These cells play a crucial role in the activation of the autoimmune response, which is thought to cause MS-line symptoms in these mice.
This research has revealed how fiber can impact Th1 cells, and has suggested that biochemical variations in how fiber is structured might change how they influence immunity, or autoimmunity.
Over the past few decades in the industrialized world, there has been a rapid increase in the prevalence of autoimmune and inflammatory disorders. This indicates that people's dietary choices are influencing the incidence, noted senior study author Dr. Lisa Osborne, an assistant professor at the University of British Columbia (UBC). "Dietary fibers are potent modulators of immune responses and can control inflammation in multiple diseases, but they're a very biochemically diverse family. Our study gives us a clearer window into the potential of several sources of fiber in maintaining immune health."
"Guar beans aren't that common in western diets, and the gum isn't used at these high levels as an additive in the west," noted first study author Naomi Fettig, a graduate student at UBC.
The researchers noted that studies have indicated that fiber is beneficial for health, and it's good to have a variety of sources in the diet. This research has shown that different types of fiber can have very different impacts.
The average American or Canadian person's intake of fiber, at 15 grams, is half the recommended daily allowance of 30 grams.
"Incorporating guar beans might be challenging to achieve at the doses we gave to mice," Osborne acknowledged. "But a guar gum derivative, partially hydrolyzed guar gum, is commercially available as a prebiotic."
The researchers want to learn more about how guar gum is beneficial to physiology.