A prebiotic is basically dietary fiber, that is components of the diet that our organism cannot digest and reach the large intestine in a practically unaltered form where they act as a substrate to be fermented by the indigenous intestinal microbiota (or intestinal flora) there, making the latter grow and proliferate.
Therefore, in order for the prebiotic to reach the large intestine practically intact, it must be able to show resistance to being metabolized or hydrolyzed in the previous stages (stomach, small intestine), that is, it must be able to withstand gastric acidity and digestive enzymes and not be altered by them.
The official definition of prebiotic, as established by the World Gastroenterology Organization (WGO) in its report of February 2017 is that of a “selectively fermented ingredient that results in specific changes in the composition and/or activity of the gastrointestinal microbiota, thus conferring benefit(s) upon host health”.
Although they only differ in one letter, we should not confuse Prebiotic with Probiotic. A probiotic is a microorganism while a prebiotic is a substrate, a “food” for bacteria.
Prebiotics are essentially molecules of carbohydrates linked together in a chain to form a polysaccharide. Depending on the types of molecules that form the polysaccharide and the type of chemical bond that joins them, it will be one prebiotic or another.
The most common prebiotics that can be found on the market as a dietary supplement are
- Inulin Fiber.
- FOS (Fructooligosaccharides).
Inulin fiber is a type of polysaccharide formed by several molecules of fructose joined in a chain giving rise to a fructan. Our body lacks enzymes that can hydrolyze the bonds that bind these fructose molecules, however, our intestinal microbiota can. Thus, the native microbiota metabolizes inulin and grows in the presence of this substrate that it uses to produce energy and generate metabolites (short-chain fatty acids) that our body needs.
In nature, inulin fiber is present in many plants, being the Agave, Jerusalem Artichokes tubers or in the Chicory Root, from where this prebiotic is usually extracted.
FOS (Fructooligosaccharides ) are closely related to inulin fiber since they are in fact derived from the hydrolysis of inulin.
Inulin and FOS Fructooligosaccharides benefits:
They provide great benefits to the body as they are:
- Encourage the growth of Bifidobacteria and Lactobacillus at the level of the colon.
- Produce short chain fatty acids by reducing the pH of the intestinal environment and creating a hostile environment for the growth of potentially pathogenic species.
- To promote the absorption of calcium, magnesium and iron.
- Absorb water as they pass through the intestine favoring gastrointestinal transit.
- Increasing the weight of the feces
- They can promote the growth of certain bacteria that give rise to metabolites that promote the growth of other beneficial bacteria.
Inulin fiber and FOS fructooligosaccharides may present some intolerance problem such as flatulence or presence of gases as a result of the fermentation process. It is important to adjust the dose well, which can be set at about 2-3 doses/day of 5 g each, but should be reduced if these symptoms of intolerance are present.
We can find in the market both inulin fiber powder and FOS:
Chicory Root Inulin
Jerusalem Artichoke Inulin
Pectin is another group of fibers that have their origin in some vegetables and in the skin of some fruits and citrus fruits (apple, lemon).
Although it exerts similar processes to the FOS and Inulin, the ingestion of fruit pectin is also associated with the growth of Faecalibacterium prausnitzii, a very important species in the intestinal microbiota since it produces short chain fatty acids, specifically butyric acid, very important for the energetic contribution to the intestinal epithelial cells and for its anti-inflammatory capacity.
Some of the Apple Pectin products we can find in the market:
Polyphenols – Resveratrol
Polyphenols are substances naturally found in plants, fruits, vegetables, as well as in other products such as chocolate or red wine.
Their main characteristic is their ability to act as antioxidants.
One of the best-known polyphenols is Resveratrol, a polyphenol from grapes with antioxidant and anti-aging properties.
At the intestinal level, resveratrol promotes the growth of Akkermansia muciniphila, a microorganism present in the intestine and with a fundamental function in the regeneration of the intestinal epithelium.
Resveratrol exists in two isomers: trans resveratrol and cis resveratol. The common form we usually find in the market is the trans resveratrol isomer as this is the most active isomeric form.
Some products that we can find in the market with trans resveratrol: