What are prebiotics?
The scientific definition of a prebiotic is “a substrate that is selectively utilized by host microorganisms conferring a health benefit”. Often, prebiotics are types of soluble fiber that humans cannot digest but instead serve as ‘food’ for beneficial microbes that already live your colon or elsewhere in your body.
What can prebiotics do for health?
Both for healthy people and those with certain health concerns, prebiotics are a promising way to modulate your gut microbiome for better health. While there are more studies to date on probiotics than on prebiotics, research on prebiotics is rapidly expanding. Researched health benefits of specific prebiotic substances include:
- Improving calcium absorption
- Regulating blood sugar
- Enhancing colonic bacterial fermentation to reduce gut transit time
These physiological benefits may have positive effects in those with osteoporosis, diabetes, and colorectal cancer, respectively.
Research has also suggested that prebiotics may support your immune system and encourage favorable metabolic activities by your resident gut microbes. Newer studies are investigating the role of prebiotics in the management of some gastrointestinal conditions such as irritable bowel syndrome and inflammatory bowel diseases (ulcerative colitis and Crohn’s disease). In the future, specific prebiotics could be designed to boost numbers of beneficial bacteria known to be less abundant in the systems of people affected by these and other conditions.
How can I get more prebiotics?
Consuming certain foods and supplements can increase dietary intake of prebiotics. Plants that are rich in prebiotics include onions, garlic, bananas, chicory root, and Jerusalem artichokes. Prebiotics may also be added to some food items such as certain yogurts, cereals, breads, biscuits, desserts, or drinks. The word ‘prebiotic’ is seldom used on the label; instead, look in the ingredients list for galacto-oligosaccharides (GOS), fructo-oligosaccharides (FOS), oligofructose (OF), chicory fiber, or inulin. Consuming at least 5 grams of prebiotics daily is recommended for improved gut health.
Prebiotics are also found in breast milk. Human milk oligosaccharides (HMOs) are prebiotics that enhance beneficial microbial populations in the infant gut while discouraging pathogens that may cause infections. Many brands of infant formula are now supplemented with oligosaccharide prebiotics to mimic this effect, and HMO-enriched formulas are also available in some places.
Are prebiotics safe?
When you eat foods such as garlic or onions that naturally contain prebiotics, there are no safety concerns as long as you can tolerate those foods. Prebiotics that are used as extra ingredients to foods or supplements that have been tested in clinical trials and shown to be safe for consumption by the generally healthy population.
Are there any downsides to prebiotics?
With high intake of prebiotics, some people experience minor digestive discomfort. It’s a good idea to start with low doses of prebiotics and gradually increase your daily consumption to a level that’s effective. If you have symptoms, they may subside once your body adapts.
Prebiotics are not an alternative to a diverse and healthy diet. Eating a range of whole grains, fruits and vegetables, and other fiber-rich foods in addition to prebiotics can help you enjoy better digestive health and overall health.
Prebiotics and probiotics may be taken at the same time. When one product delivers both, it is called a synbiotic. Although in theory a probiotic could be matched with a prebiotic that will improve the probiotic’s function, few studies have demonstrated this synergy. The specific combination of prebiotic and probiotic has to be carefully researched if the goal is to consume health-benefitting live microorganisms along with the exact substrate that they need to grow.
See here for resources that will help you find a prebiotic product to suit your needs.
Get the facts on prebiotics
This educational infographic called “Prebiotics” gives you the basics of prebiotics in supplements or in foods.
What effects do prebiotics have on the gut microbiota?
This infographic, called “Effects of probiotics and prebiotics on our microbiota”, shows how both probiotics and prebiotics interact with the microbes in your digestive tract.
Prebiotics and fiber: Are they the same?
It’s a common misconception that prebiotics are the same thing as dietary fiber. This infographic, called “Understanding prebiotics and fiber”, helps you understand the difference between the two categories.
Check out this ISAPP educational video, created by our science translation committee to give a quick overview of prebiotics and how they affect health.