The concept of prebiotics is more recent than that of probiotics, having been initially proposed by Gibson and Roberfroid in 1995 [2]. The key aspects of a prebiotic are based on the idea that “the host cannot digest them and they benefit health by positively influencing beneficial native microbes.”

The use of prebiotics or probiotics aims to influence the intestinal environment dominated by trillions of commensal microbes, in order to benefit human health. (World Gastroenterology Organization, 2017).

What are prebiotics?

“Prebiotics are food ingredients that have the potential to benefit the host by selectively stimulating the growth of certain microorganisms in the gastrointestinal tract” (FAO/WHO, Piñeiro et al., 2008).

Prebiotics are non-digestible food ingredients that selectively support the growth of beneficial bacteria in the gut. Research suggests they may improve digestive health, heart health, weight management, and nutrient absorption.

The term prebiotic refers to foods containing ingredients that the body cannot digest but that improve health by promoting beneficial intestinal bacteria growth, such as fructooligosaccharides.

Accepted uses of prebiotics

Different oligosaccharides have been shown to stimulate bifidobacteria in the gastrointestinal tract.

These bacteria can reach levels similar to those seen in breastfed infants.

Benefits include:

• Inhibition of pathogens
• Reduction of ammonia levels
• Production of vitamins and digestive enzymes

Prebiotics act like fiber through several mechanisms:

• Serve as substrate for beneficial bacteria
• Reduce intestinal acidity
• Limit pathogenic bacteria growth
• Reduce toxic compounds

Inulin and fructooligosaccharides (FOS)

Inulin and FOS are the most widely used prebiotics.

Natural sources include:

• Chicory
• Onion
• Artichokes
• Garlic

Inulin consists of chains of fructose molecules and can be hydrolyzed into FOS.

It is classified as GRAS (Generally Recognized As Safe), ensuring safe consumption.

Categories of prebiotics

Common prebiotics include:

• Oligofructose
• Inulin
• Galacto-oligosaccharides
• Lactulose
• Human milk oligosaccharides

Lactulose is a synthetic disaccharide used to treat constipation and hepatic encephalopathy.

Characteristics of prebiotics

To be classified as a prebiotic, a substance must:

• Be of plant origin
• Be a complex molecule
• Resist digestion
• Be partially fermented by colonic bacteria
• Be osmotically active

Short-chain fatty acids (SCFA)

SCFAs include:

• Butyrate
• Acetate
• Propionate

Butyrate:

• Provides energy to colon cells
• Promotes cell growth and differentiation

Dosage and tolerance

Studies show dose-response effects for inulin and FOS.

• High intake may cause gas
• Recommended intake is less than 5 g/day
• This is sufficient for bifidogenic effect

Conclusion

Prebiotics provide multiple intestinal benefits, especially in the colon:

• Improve bowel transit
• Help relieve constipation
• Reduce pathogens
• Improve stool formation

Prebiotics feed probiotics and are essential for their function.

They provide natural fiber and enhance gastrointestinal health.

Document prepared by Octavio Davila | Scientific Directo