Why Root Veggies Are Great for the Gut Microbiome


When it comes to digesting carbohydrates, root veggies are difficult to beat: foods like sweet potatoes, carrots, and cassava aren’t just delicious, they are also great sources of vitamins, minerals, phytochemicals, and fiber. (Make Sure You check out my articles The case for Much More Carbs: Insulin’s Non-Metabolic Functions in the Human BodyJust How Many Carbs Should We Eat? 5 Weird Root Vegetables Everyone Should Attempt and Potatoes: Friend or Foe? )

Fortunately for us origin fans, these vegetables come with another major benefit too: they are a total blessing for our gut microbiota! Most root fruits have powerful antibacterial properties (try saying that five times fast!) , feeding the beneficial bacteria in our colon and supporting a healthy makeup of gut microbes (see What Is the Gut Microbiome? And Why Should We Care About It? To get a deeper dip into just what the microbiome is and why it is so significant!) . Let us take a peek at the special ways root veggies help maintain a healthy area of intestine creatures.

Increased Bifidobacteria and Lactobacilli

Root vegetables contain many different carbohydrates that nourish two major classes of probiotic bacteria: Bifidobacterium and Lactobacillus. Bifidobacteria carry a enormous number of roles, such as producing vitamins, preventing pathogens from colonizing the gut mucosa (including E. coli), protecting against yeast overgrowths, improving the gut barrier function, and reducing endotoxin transport. Likewise, lactobacilli (including the most popular probiotic, Lactobacillus acidophilus) help inhibit the growth of pathogens like H. pylori (through a process known as”competitive exclusion”), and a few species have anti-cancer and anti-diabetic consequences. Essentially, these bacteria are essential probiotic residents of a healthy gut, so it’s crazy important to make choices that encourage their growth!

And, root vegetables are all well-proven promoters of these extraordinary microbes! In 1 study using an in-vitro fermentation system together with human fecal slurry, two different sweet potato varieties significantly elevated amounts of Bifidobacterium over the duration of 24 hours. Cassava (a starchy root that’s also the source of tapioca) has additionally been shown to excite bifidobacteria and lactobacilli development. At a study of oligosaccharides free from cassava infusion, amounts of Lactobacillus gasseri (which has important anti-inflammatory activity) and Bifidobacterium breve (that can potentially enhance fat metabolism and skin health) increased dramatically, while also boosting populations of Lactobacillus reuteri (which produces vitamin B12 and folate), Lactobacillus acidophilus (which will help revive the microbiota following antibiotic treatment), and Bifidobacterium adolescentis (which decreases the mineral-binding effects of phytic acid) to varying degrees. In rats, consuming crackers included of cassava fiber and wheat germ (in ratios of 60:40 or even 50:50) led to an increased Lactobacillus count, and in mice, xylooligosaccharides derived from cassava dregs (another byproduct of cassava starch processing) was also shown to foster the rise of Bifidobacterium along with Lactobacillus species. In a different study, inulin expressed from burdock root (a vegetable common in northern Asian cuisines, and which makes a excellent addition to stir fries, braises, and soups!) Significantly promoted counts of lactobacilli and bifidobacteria in vitro.

In many other studies, Jerusalem artichokes (compared to actual artichokes!) Managed to improve levels of several Lactobacillus along with Bifidobacterium species across a variety of creatures, because of the high concentration of fructooligosaccharides (or even FOS), a subtype of inulin that isn’t digested in the small intestine and acts as a potent prebiotic for colonic microbes. Another origin veggie full of FOS is yacon (a slightly sweet tuber native to the Andes), and animal studies have also proven that a diet full of yacon or yacon sugar enhances the development of bifidobacteria and lactobacilli. One rat research found that in one week of ingesting a diet containing 10 percent yacon origin, the intestinal environment was considerably altered as a result of the abundant fermentation of yacon, leading to a substantial increase in Lactobacillus acidophilus, Bifidobacterium pseudolongum, along with Bifidobacterium animalis. (A few yacon crops contain around 70% fructooligosaccharides on a dry-matter basis, therefore it’s not surprising this root veggie is a powerful prebiotic!)

Enriched SCFA Production

Short-chain fatty acids, or SCFAs (including butyric acid, acetic acid, and propionic acid) are produced from fiber cessation by specific bacteria groups at the gut. Together with serving as the main food source of intestinal epithelial cells, SCFAs give you an enormous collection of benefits for our wellbeing, including reducing the chance of inflammatory diseases, protecting against diabetes and obesity, and lessening the probability of heart disease. Also, it just so happens that the carbs which get fermented to SCFAs are present abundantly in many root vegetables, like pectin (saturated in carrots), fructooligosaccharides (plentiful in Jerusalem artichokes, burdock root, chicory root, and also yacon), and immune in the form of RS3 (high in cassava and cooked and cooled potatoes) (for much more on immune starch, including why RS3 might be superior to some other resistant starch subclasses, watch Resistant Starch: It’s Not All Sunshine and Roses! )

In vitro, orange-fleshed sweet potato purees have been proven to improve production of butyric acid when fermented by bacteria that were human. Scientists have also tested polysaccharides extracted in purple sweet potatoes (like water-soluble polysaccharide [WSP], dilute alkali-soluble polysaccharide [DASP], also concentrated alkali-soluble polysaccharide [CASP]) on normal mice as well as those treated with the immunosuppressing drug cyclophosphamide. All three polysaccharides improved the creation of acetic acid, propionic acid, and butyric acid in normal mice, whereas the saltwater polysaccharide improved the creation of these SCFAs one of cyclophosphamide-treated mice.

In rodents, diets supplemented by yacon or yacon flour have been demonstrated to increase levels of SCFAs. Rats fed a diet containing 6% fructooligosaccharides and inulin out of yacon (in comparison to some yacon-free management diet) experienced a beneficial modulation of the intestine microbiome, such as a significant increase in butyrate levels. The following rat study found a diet containing 10 percent yacon root led to SCFA production that was 70% more compared to fructooligosaccharides alone were used, indicating non-FOS components of yacon were being fermented to SCFAs, also!

And, when it comes to SCFAs, potatoes deserve a special mention! Potatoes which have been cooked and chilled to make retrograded resistant starch are demonstrated to greatly enhance SCFA production, as has raw potato starch. And, continuing ingestion of resistant starch from potatoes seems to spoil the microbiota over the time to generate more SCFAs. In a study of rats, for example, resistant potato broccoli had a butyrogenic impact that increased over time, with butyrate production increasing six-fold following six months of ingestion in comparison to half a month of ingestion. (That suggests a slow elastic process happening within the GI tract, making a strong case for consistently including resistant carbohydrates in our diets for maximum SCFA-producing benefit!) . See Potatoes: Friend or Foe of Paleo?

Intriguingly, distinct sources of tomatoes can have significantly different effects on SCFA creation, and it ends up that RS3-containing root veggies may have some advantages over RS3-containing grains! That is because even within immune starch subclasses, subtle variations in structure might influence the reaction of the microbiota. For instance, based upon the food source that they come from, the double-helix form formed in retrograded resistant starch (RS3) results in crystalline entities with unique shapes which support the growth of different bacteria. What scientists call the”A-type polymorphic form” (made from cereal grains) kinds double-helix shapes with a more compact, more dry arrangement, while the”B-type polymorphic shape” (generated from tubers using a high amylose content) forms a more receptive helix shape with higher water content. In studies, B-type forms result in higher butyrate production than A-type forms, implying that foods such as cassava and cooked and chilled potatoes are better for increasing butyrate amounts than grains are!

Decreased Pathogen Infection

For a result of altering the gastrointestinal environment, root vegetables can help prevent pathogens from colonizing and damaging the intestine! In rats, grain products supplemented using cassava fiber led to reduced levels of Escherichia coli from the animals’ feces (while also promoting a greater abundance of probiotic bacteria), indicating an ability to suppress the development of some pathogens while enabling the”good guys” to thrive. In mice, elements of cassava origin proved likewise demonstrated to reduce the amount of all Escherichia coli present.

And, some origin veggies contain compounds apart from fiber that suppress pathogen development. Yacon, for example, comprises natural antibacterial compounds, according to the simple fact that yacon crops require almost no pesticides to nurture! A few of these materials have antibacterial action against not only plant pathogens, but also ones known to infect people, such as Bacillus subtilis and Staphylococcus aureus. 1 mouse experiment even showed that yacon flour could stop intestinal infection from Salmonella enterica serovar Typhimurium (S. Typhimurium), as a result of its ability to boost non-specific immunity and improve the adrenal gastrointestinal obstruction. Even carrots contain compounds which reduce pathogen development. In one experiment, extracts out of peeled and shredded carrots were able to inhibit a range of harmful bacteria including Listeria monocytogenes, Staphylococcus aureus, Pseudonomas fluorescens, Candida lambica, and Escherichia coli.

Enhancing the Bacteroidetes/Firmicutes Ratio

Across multiple studies, the proportion of Bacteroides into Firmicutes (two big germs phyla) was connected with obesity, using a greater ratio (greater Bacteroidetes) associated with leanness, and a decrease ratio (more Firmicutes) correlated with higher body fat. In immunosuppressed mice, three purple sweet potato polysaccharides raised the relative abundances of Bacteroidetes while lowering the levels of Firmicutes, helping move the microbiota in the direction associated with leanness!

Root Veggies for the Win!

So that we have itin case we needed more reasons to add these delicious, versatile, and nutrient-packed veggies into our diet, we could do it to our intestine!


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The article Why Root Veggies Are Terrific for your Gut Microbiome appeared on The Paleo Mom.

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