Background
A Practical Guide to Understanding Prebiotics
Abstract

A quick guide explaining what prebiotics are, the different types of probiotics, the mode of action of prebiotics and its health benefits.

7 minutes
PDF
Download PDF

What are prebiotics?

Prebiotics are dietary substances resistant to digestion and selectively fermented in the large intestines to promote specific changes in the composition and activity of beneficial gastrointestinal microflora1,2. Oligosaccharide prebiotics in particular, can stimulate the growth of Lactobacillus and Bifidobacterium3, which have been associated with the health and well-being of the host1-3.
 

What types of prebiotics are available?

Common prebiotics (non-digestible carbohydrates) can be grouped into the following categories listed1,4:

1. Human milk oligosaccharides (HMO)

2. Lactulose

3. Galacto-oligosaccharides (GOS)

4. Inulin-type prebiotics or inulin-type fructans - which includes inulin, fructo-oligosaccharides (FOS) and oligofructose (OF)

  • Inulin-type prebiotics are members of a larger group called 'fructans'. Fructans are primarily polymers of fructose units, with a specific bonding profile between the sugars2
  • These prebiotics can be broken down into broad subgroups based on degree of polymerization2. Please refer to below table1,2,4-12:

 

Type

Natural Food Source

Manufacture method

Degree of polymerization

Usage in food products

HMO

Human milk5

A large variety found in human milk, complex to mimic6

Large structural diversity7

Addition to infant formula being explored5

Lactulose

Only formed during heat treatment by isomerization of lactose8

Polymerising one unit of fructose with one unit of galactose1

 

Disaccharide1

Used as a drug for treatment of constipation and hepatic encephalopathy1

GOS

Produced from lactose9

Enzymatic transgalactosylation of lactose7

2-84,7

Added in milk formula and infant foods, beverages, meal replacers, fermented milks, and confectionery products10

Inulin-type prebiotics

Inulin

Naturally in plants such as root vegetables including burdock, chicory, leeks, onions1

Extraction from chicory roots, contains FOS molecules11,12

11-6511

Added in milk formula and infant foods, beverages, yogurts, biscuits, dietary supplements9

 

Short chain FOS (scFOS)

Enzymatic synthesis from sucrose2

2-64,7

 

Long chain FOS (lcFOS)

Enzymatic synthesis from sucrose2

7-60 (average 25)4,7

 

OF

Enzymatic partial hydrolysis of inulin1,2

< 10 (average 4)

Please note the above table was collated from different authors who defined types of prebiotics, however terms are not universal and uses have been inconsistent across papers.
 

The metabolism of prebiotics4:

  • Non-digestible carbohydrates are fermented in the colon to short chain fatty acids (SCFA - mainly acetate, propionate and butyrate), metabolites and gases such as hydrogen and carbon dioxide
  • Beneficial effects can be related to the metabolism of Bifidobacteria, with their end products from fermentation:
    • Bifidobacteria have the capacity to produce vitamins and antioxidants
    • SCFA reduces the gastrointestinal pH to suppress the growth of pathogens, consequently supporting immunity, while also contributing energy
       

Prebiotic effects and potential health benefits:

Supplementation in infant formula was associated with:

Intake in adults was associated with:
  • Change of gut microbiota profile, especially increasing fecal concentration of Bifidobacteria4
  • Improved stool quality and frequency4,13
  • Reduced risk of gastro-enteritis4
  • Reduced risk of certain allergic reactions and types of infections, as suggested by preliminary data4,13
  • Ability to modulate certain immunological

biomarkers, affecting immune activities4

  • Improved pathogenesis of irritable bowel disease

(IBD) with changes in gut microbiota composition4

  • Reduction in colon cancer risk and increased calcium absorption, as suggested by preliminary evidence1,4

There should be further studies to help confirm the health benefits listed above and the relevant clinical significance4,13.
 

How much prebiotics do we need?

  • Individual response to an identical dose of prebiotics can be variable. It is suggested bifidogenic effects may be influenced by the existing gut flora2. For example, the growth of a strain of bacteria that was previously present in a low number might be greater after supplementation, than if it was present in a high number.
  • There is currently no consensus on a recommended intake for prebiotics, however there is some evidence suggesting a minimum dose of 2.5 g inulin-type prebiotics daily is needed to produce a bifidogenic effect in adults, with a dose-response relationship up to 10 g per day2.

For infants, recommendations on dosages are currently unavailable, but existing scientific research suggests administration of prebiotic-supplemented formula to healthy infants does not raise safety concerns in terms of growth and adverse effects13.
 

For more nutritional information, please view https://Singapore.wyethnutritionsc.org
This material is for healthcare professional reference only. Wyeth® is a registered trademark of Wyeth LLC. Used under license.

Reference
  1. Guarner F et al. World Gastroenterology Organization global guidelines: probiotics and prebiotics October 2011. J Clin Gastroenterol. 2012;46(6):468-481.
  2. Kelly G. Inulin Type Prebiotics – A Review: Part 1. Altern Med Rev. 2008;13(4):315-329.
  3. Shoaf K et al. Prebiotic galactooligosaccharides reduce adherence of enteropathogenic Escherichia coli to tissue culture cells. Infect Immun. 2006;74(12):6920-6928.
  4. Roberfroid M et al. Prebiotic effects: metabolic and health benefits. Br J Nutr. 2010;104(S2):S1-63.
  5. Moreno FJ and Sanz ML. Food oligosaccharides: Production, analysis and bioactivity. New York: John Wiley& Sons; 2014.
  6. Arslanoglu S. Early dietary intervention with a mixture of prebiotic oligosaccharides reduces the incidence of allergic manifestations and infections during the first two years of life. J Nutr. 2008;138(6):1091-1095.
  7. Boehm G and Moro G. Structure and functional aspects of prebiotics used in infant nutrition. J Nutr. 2008;138(9):1818S-1828S.
  8. Luzzana M et al. Milk lactose and lactulose determination by the differential pH technique. Le Lait. 2003;83:409-416.
  9. Nittynen L et al. Galacto-oligosccharides and bowel function. Scand J Food Nutr. 2007;51(2):62-66.
  10. Torres D et al. Galactooligosaccharides: Production, properties, applications and significance as prebiotics. Compr Rev Food Sci F. 2010;9:438-454.
  11. Macfarlane S et al. Review article: prebiotics in the gastrointestinal tract. Aliment Pharmacol Ther. 2006;24(5):701-714.
  12. Thomas DW et al. Probiotics and prebiotics in pediatrics. Pediatrics. 2010;126(6):1217-1231.
  13. Braegger C et al. Supplementation of infant formula with probiotics and/or prebiotics: A systematic review and comment by the ESPGHAN Committee on Nutrition.
Locked
On
FAB action liks
Share
Messenger
WhatsApp
Copy Link
Search
On
Register
Off
Save (for later)
On
Share it