A person diagnosed with metabolic syndrome has at least three of the five following medical conditions:
Abdominal (central) obesity;
Elevated blood pressure;
Elevated fasting plasma glucose;
High serum triglycerides (triglycerides are a type of fat found in the blood);
Low high-density lipoprotein (HDL) levels.
With the syndrome there is a high risk of developing cardiovascular disease and diabetes. The term “metabolic” refers to the biochemical processes involved in the body’s normal functioning. The syndrome is a “modern disease” and metabolic syndrome is becoming more common due to a rise in obesity rates among adults. Figures relating to the U.S., for instance, suggest 34 percent of the U.S. population have metabolic syndrome ,as revealed by the American Heart Association.
There could be some hope on the horizon. A South Dakota State University indicates that adding resistant starch to diets for people with metabolic syndrome alters the microbiome of the gut, increasing the levels of beneficial bacteria. In turn this lowers bad cholesterol and decreases inflammation, reducing the health effects of obesity. A microbiome is the ecological community of commensal, symbiotic, and pathogenic microorganisms that literally share our body space. Microbiomes form in different ecological niches (as with the area of interest here – the microbiome of the gut.)
The new study has focused on a prebiotic. Prebiotics are substances that induce the growth or activity of microorganisms (e.g., bacteria and fungi) that contribute to the well-being of their host. Probiotics, in contrast, involve the ingestion of live bacteria with the aim of changing a microbial community through adding to the total population.
The prebiotic under examination is a resistant starch type 4 known as RS4. This is a form of non-digestible, chemically modified wheat fiber. Because the starch cannot be digested in the upper gastrointestinal tract it becomes fermented by the gut bacteria in the colon. This process produces chemicals, such as short-chain fatty acids. These chemicals may exhibit beneficial health effects.
To look into this, a study was set-up using 12 women and 8 men with metabolic syndrome. The people were drawn from the eastern South Dakota community. The RS4 starch was incorporated into flour and each of the subjects eat community meals, based on the same foods. The subjects were not told that their food had been fortified (in research, this is what’s known as a ‘blinded’ study.)
The study ran for 12 weeks. Over this time stool and blood samples were collected and tested to study the bacterial populations. Regular checks of the subjects’ weight and health were made. Assessment included running a DEXA (dual energy X-ray absorptiometry) scan. This is a special type of X-ray that measures bone mineral density.
It was found that the modified diet lowered all types of cholesterols. A small decrease in average waist circumference and body fat percentage also occurred with each person. The microbial analysis revealed a corresponding alteration to the microbiome composition, with a rise in beneficial bacteria in the gut.
While the results are interesting, the study was relatively small and further research will be needed to verify the findings. In addition, simply adding resistant starch to some food is insufficient if other types of less-healthy food are eaten and people do not engage in regular exercise. No complete ‘magic pill’ exists for weight loss.
The research has picked up interest on social media. Medical doctor Dr. Joseph Mercola (@mercola), for example, tweeted: “Digestive-resistant starch is important for gut health to promote regular bowel movements.” While health expert Mike Sheridan (@coachmiketweets) quipped: “Resistant Starch – Worth Carb-ing Up For?”
The research is published in the journal Scientific Reports. The paper is titled “Impact of dietary resistant starch type 4 on human gut microbiota and immunometabolic functions.”
This article is part of Digital Journal’s regular Essential Science columns. Each week we explore a topical and important scientific issue. Last week we traced how West Nile virus is leading to memory loss due to a change with the immune system. The week before we explored how a limitation with wearable technology — being brittle — could be overcome a new self-healing material.
