Dietary fiber improves symptoms of metabolic syndrome.
Metabolic syndrome is a constellation of medical conditions that includes high blood pressure, high blood glucose, unhealthy cholesterol levels, and excess abdominal fat. Having metabolic syndrome increases a person’s risk of heart disease, stroke, and diabetes. A 2009 study found that supplemental psyllium and guar gum improved symptoms associated with metabolic syndrome.
Psyllium, found in husks of the psyllium (Plantago ovata) seed, and guar gum, found in guar beans and commonly used as a food additive, are types of soluble dietary fiber. Soluble fibers dissolve in water and pass intact into the large intestine, where they are converted by colonic bacteria to prebiotic gels. Evidence indicates that consumption of soluble dietary fibers is associated with improved metabolic function, cardiovascular health, and gut function.
The six-month study involved 141 adults (average age, ~58 years) who had metabolic syndrome. The investigators randomly assigned participants to one of three groups. One group consumed supplemental psyllium husk powder twice a day before meals, while the other consumed guar gum. The third group consumed a standard diet. Investigators measured the participants' metabolic markers, blood lipids, blood pressure, and body weight before and after the intervention.
Participants who consumed the psyllium and guar gum exhibited reduced blood glucose, insulin, low-density lipoprotein cholesterol, and apolipoprotein B (a component of very-low-density lipoprotein), compared to their baseline levels. Those who took the psyllium showed marked improvements in their triglycerides (~13 percent lower) and blood pressures (systolic, ~4 percent lower; diastolic, ~3 percent lower). Those who took the guar gum lost slightly more weight than those who took the psyllium. Participants who followed the standard diet did not exhibit significant improvements in any measures.
These findings suggest that soluble dietary fibers such as psyllium and guar gum reduce weight and improve markers of metabolic health in people with metabolic syndrome. Dietary fibers also maintain gut barrier function, which is often impaired in metabolic syndrome due to increased intestinal permeability. Learn more about intestinal permeability in our overview article.
The science digest is a special email we send out just twice per month to members of our premium community. It covers in-depth science on familiar FoundMyFitness related topics.
If you're interested in trying out a few issues for free, enter your email below or click here to learn more about the benefits of premium membership here.