Prebiotics are non-digestible dietary fibers that selectively stimulate the growth of beneficial colon bacteria in the host’s microbiota. Bifidobacteria and lactobacilli are the most well-known of them.
Prebiotics are complex carbohydrates that are not digested by the upper gastrointestinal tract, but rather are fermented in the final section by “good” bacteria present in the colon. Consequently, they are not a source of energy for intestinal cells, but are essential substrates for certain microorganisms, particularly in the vaginal and intestinal microbiota.
Where can you find prebiotics?
Diet is the only source of prebiotics; it’s by eating that you feed your microbiota and thereby influence its diversity and composition. Therefore, a varied diet, favoring foods high in fiber like fresh fruit and vegetables, is the key element in preserving the equilibrium in bacterial flora.
The most-used prebiotics are fructans, particularly inulin, and fructooligosaccharides. Some foods are particularly rich in them:
- bananas, tomatoes, onions, and garlic contain oligosaccharides,
- endives, chicory, and artichokes contain inulin,
- dry pulses and complete cereals contain resistant starch.
Prebiotics, effects to be confirmed
Prebiotics have great therapeutic potential for diseases associated with dysbiosis, like infectious intestinal diseases or allergies. Nevertheless, like with probiotics, it will be necessary to identify the kind of prebiotic to use, the dose, the route of administration, and to confirm their effectiveness.