Global Prebiotics Week
Global Prebiotics Week takes place during the first week of November each year and aims to raise awareness on the importance of prebiotics for the gut microbiota1.
What are prebiotics?
Prebiotics are scientifically defined as “a substrate that is selectively utilized by host microorganisms conferring a health benefit”2. In other words, prebiotics are the food for the beneficial gut microbes, often categorised as dietary fibre that is not broken down by the human digestive system (learn more about the digestive system here).
The gut microbes living in the digestive system, particularly in the large intestine, make up a community of microorganisms called the gut microbiota. Prebiotics are specific types of dietary fibre, often soluble fibre, that make their way through the digestive tract to the large intestine. Here, they are broken down by beneficial gut microbes like bacteria, viruses, and fungi to create energy for their biological processes. Consuming 5g of prebiotics per day is recommended for gut health2.
Prebiotics in the diet
Prebiotics can be found in small quantities in a variety of fruits (such as apples and bananas), vegetables (such as onion, garlic and Jerusalem artichoke), beans, pulses and grains. In food products and supplements, the term ‘prebiotics’ is rarely featured on the label. Instead, you may see galacto-oligosaccharides (GOS), fructo-oligosaccharides (FOS), oligofructose (OF), chicory fibre, or inulin2. Prebiotic supplements are another source of prebiotics in the diet; however, a food first approach is encouraged.
During infancy, children consume prebiotics in breastmilk from the naturally occurring Human Milk Oligosaccharides (HMOs) to feed their newly formed gut microbe community and develop their immune system2. Infant formulas now include prebiotic supplements to simulate the naturally occurring prebiotics in breastmilk. This is important for development of the immune system and the brain during childhood2.
Increasing prebiotic intake for gut health
Increasing dietary fibre intake is a good place to start to improve the chances of consuming enough prebiotics. The daily recommendation for fibre intake is 24-25g and 30g per day, in Ireland and the UK, respectively3,4. However, only around 10% of the population reach this daily intake3. Aim to gradually increase intake for fruits, vegetables, nuts, seeds, beans, pulses and grains throughout the day to increase fibre and prebiotic intake.
Dietary fibre can support the health of the digestive system through the fermentation of fibre and reducing transit time of stool. Fibre can support the absorption of vitamins and minerals, as well as regulating blood sugar levels 2. It also keeps us fuller for longer which can support weight management and reduce the risk of heart health5.
It is important to note is that not all fibre is a source of prebiotics. Different types of fibre-based foods will be a source of different structures of prebiotics5. Gut microbes have enzymes to break down specific prebiotic structures within the food we eat5. For this reason, a varied diet with fibre from a diverse range of plant-based foods will increase the chance of consuming enough prebiotics in the diet.
- Global Prebiotic Association: Global Prebiotics Week (2021) https://prebioticassociation.org/global-prebiotics-week-2/ (Accessed: October 2021)
- Gibson et el., (2017) Nature Reviews Gastroenterology & Hepatology, 14(1):491–502 https://www.nature.com/articles/nrgastro.2017.75
- Public Health England, National Diet and Nutrition Survey https://www.gov.uk/government/statistics/ndns-results-from-years-9-to-11-2016-to-2017-and-2018-to-2019 (Accessed: October 2021)
- Irish Nutrition and Dietetic Institute, Fabulous Fibre https://www.indi.ie/diseases,-allergies-and-medical-conditions/digestive-health/1248-fabulous-fibre.html (Accessed: October 2021).
- Holscher et al., (2017) Gut Microbes, 8(2): 172–184 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5390821/