Guide to Prebiotics

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In this day and age, many consumers are well aware of the health benefits that come along with a diet rich in fiber and probiotics. Prebiotic foods, however, are commonly lacking from the typical American diet. Probiotics are living microorganisms that benefit the digestive system of their host. Prebiotics contain non-living, indigestible fiber that passes through the human gastrointestinal system without significant change until interaction with the microflora of the gut. Probiotic bacteria use prebiotic fiber as fuel for a variety of health-promoting actions (click here to explore the health benefits of probiotic supplementation).

What are Prebiotics?

Prebiotics are also known as “oligosaccharides” or small starch molecules (mostly fructans and galactans) that behave similarly to other forms of fiber. As with many high-fiber foods, the human gastrointestinal system cannot digest or absorb much nutrition from prebiotics alone. However, once fermented by anaerobic bacteria in the large intestine, prebiotics cause beneficial change to the composition and activity of the gut microflora, allowing for improved digestion, higher immune function, better hormonal balance, reduced stress response, lower risk for obesity and weight gain, healthier cholesterol levels, and reduced inflammation.

Although all prebiotics are fiber, not all fibers are prebiotic. In order for an ingredient to be classified as prebiotic, it must show resistance to 1) the acidity of stomach acid, 2) hydrolysis by mammalian enzymes, and 3) absorption in the upper intestinal tract. It must be fermentable by microflora in the large intestine and also selectively stimulate the growth and activity of the probiotic strains of bacteria known to promote health in the host. A few examples of fibers that qualify are inulin, oligofructose, lactulose, and resistant starch. Strains of Lactobacilli and Bifidobacteria are the probiotics targeted by most prebiotic fiber compounds, as these microbes exhibit a preference for oligosaccharides for consumption.

How Do Prebiotics Work?

The beneficial bacteria residing in the human gastrointestinal system consume prebiotic oligosaccharides for their own survival. As probiotic microflora flourish in the presence of a food source, harmful bacteria have less room to populate. Probiotic microorganisms ferment prebiotic fiber producing short-chain fatty acids (SCFAs) such as butyric acid, which is known to support the integrity of the intestinal lining. SCFAs are metabolized in the liver help to regulate electrolyte levels in the body to improve digestion and support regularity of bowel movements. SCFAs also help to stabilize blood glucose levels and decrease cholesterol synthesis. The process of fermentation lowers pH in the gut, which allows for an increase absorption of dietary minerals, stimulates immune function and further protects the bowels from harmful bacteria and other pathogens.

By fueling the beneficial gut bacteria, prebiotics have been associated with biomarkers of improved immunity, increased absorption of essential nutrients, and reduced inflammation, which is considered to be the root cause of many chronic diseases. Additionally, it has been documented that prebiotic consumption plays a role in both lipid and carbohydrate metabolism. They also have a reducing effect on cholesterol and triglyceride levels and an upregulating effect on satiety hormones. These benefits, along with effects on blood sugar regulation, make prebiotics an excellent supplement to add to a weight control regimen.

Research to support the “gut-brain connection” is still needed to strengthen early scientific claims, but there is a growing body of evidence suggesting a link between gut health and mood, depression, and anxiety. The gut is responsible for absorbing and metabolizing nutrients from both the diet and microbial fermentation. If digestion and absorption are more efficient due to prebiotic and probiotic supplementation, so will be the production and transmission of hormones and neurotransmitters that help to control mood (fear and other emotions) and relieve stress. A 2015 study published in Psychopharmacology concluded that prebiotics do indeed have a neurobiological effect on the brain and can lower circulating levels of the stress hormone cortisol.

Our Prebiotic Formula

BioMaintenance Prebiotic + Fiber supplement is an excellent option for nourishing your healthy microbiome. In only 12 calories and six grams of total carbohydrates, this supplement is jam-packed with five grams of dietary fiber, isomalto-oligosaccharides, alpha galacto-oligosaccharides, xylo-oligosaccharides, and fructo-oligosaccharides.

Isomalto-oligosaccharide is a naturally occurring, plant-based, dietary fiber. It is prebiotic, soluble, and low on the glycemic index. “Soluble fiber” means it dissolves in water as opposed to “insoluble fiber” which does not. Soluble fiber forms a gel like consistency in the stomach that slows stomach emptying, allowing the body to feel satiated for a longer period of time (yet another reason why fiber is so important to weight management). Soluble fiber also helps to reduce cholesterol absorption.

Derived from legumes, α-galacto-oligosaccharides (α-GOSs) are another variety of prebiotic, soluble fibers. They may be effective for appetite regulation, as fermentation of these prebiotics by microbes promotes the secretion of gut peptides that are known to affect both appetite and food intake control.

Xylo-oligosaccharides (XOS) can be found naturally in bamboo shoots, fruits, vegetables, milk, and honey. Fermentation of XOS leads to acidification of the colonic contents and the formation of SCFAs that serve as fuel for the function of different tissues, regulating cellular processes. XOS supplementation has been shown to significantly decrease the abundance of 3 different harmful bacteria species associated with pre-diabetes in both healthy and pre-diabetic patients. Supplementation with XOS was also found to increase the abundance of beneficial bacterial species, Blautia hydrogneotrophica.

Asparagus, sugar beet, garlic, chicory, onion, Jerusalem artichoke, wheat, honey, banana, barley, tomato, and rye are all-natural sources of fructo-oligosaccharides (FOS), or plant sugars. Fructo-oligosaccharides are often used as sweeteners in diet foods, as these sugars are indigestible by the human gut and boast a low-caloric value. To greater benefit, however, dietary or supplementary FOS increases the population of beneficial Bifidobacteria in the colon and improves the absorption of both magnesium and calcium.



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