All about Prebiotics
Written by Jerry Lau and Tommy Li
What can a good gastrointestinal health contribute to your daily wellbeing? The answers can be enhanced absorbance of nutrients, increased gastrointestinal movement and detoxification, positive moods, and more that you could think of. What if someone tells you that the bacteria in your body play important roles in digestion and are responsible for your daily happiness? In fact, many people have been taking probiotics to aid gastrointestinal health. These probiotics are live microorganisms that survive in the gut and provide the aforementioned benefits to us. The prebiotics, the so-called “nondigestible food ingredients” serve as food for the gut flora, selectively stimulate the growth and/or activity of desirable colonic bacteria (Lactobacillus and Bifidobacterium). Prebiotics contain types of fiber such as beta glucans and insulin that gut bacteria feed on. The prebiotics nourish your friendly bacteria in the GI tract to make sure your overall GI wellbeing is on point for the day (3). An easy way to differentiate between the two is that prebiotics is food for probiotics!
Prebiotics may be helpful or preventative for irritable bowel (IBS), or inflammatory bowel disease (Crohn’s disease,ulcerative colitis), colon polyps and cancer and those people with a leaky gut.In addition, prebiotics can reduce body fat and alter intestinal microbiota in children who are overweight or with obesity (1). Moreover, they can improve health by allowing growth of bacteria that facilitate the absorption of nutrients like minerals, helping food digestion, maintaining the intestinal pH and promoting intestinal peristalsis. By themselves they help to maintain a normal balance between good and bad bacteria in the gut, to control blood glucose, HbA1c and LDL, to improve symptoms of IBS. So, they are added to both regular foods and pet foods to improve overall well being for humans and animals.
Where can you find prebiotics? Prebiotics occur naturally all around us, there is no need to purchase particular pills for it. The source of prebiotics can be found in fruits like bananas and kiwi, Jerusalem artichoke, dandelion, legumes, onion, leek, garlic, honey, soybean, raw oats, whole grains like wheat, and barley, and brown rice. Note that yogurt has both bacteria and prebiotics, essentially hitting both benefits with one stone. So eat your yogurt! Prebiotics are mostly oligosaccharides, including fructooligosaccharides (FOS), galactooligosaccharides (GOS), isomalto oligosaccharides (MMOS) and xylooligosaccharides (XOS), soy oligosaccharides and inulin, polydextrose. They also contain some soluble fiber (pectin, gums). Mannan Oligosaccharides (MOS) are only for animals. Recently, calcium phosphate and chicory root (fiber-prebiotic) have also been used in manufacturing.
If you would like to purchase prebiotics and probiotics off the shelf, it is important to know which products to buy. Make sure to buy a product that has a seal of approval from testing agencies such as one from Consumer Reports/Consumer Labs. It is recommended to buy probiotic capsules packaged with insulin or other prebiotics to increase effectiveness. It is also recommended to buy probiotics in spore form, which ensures that the microorganisms can survive on the shelf and in the digestive tract (2).
References:
Nicolucci AC, Hume MP, Martínez I, Mayengbam S, Walter J, Reimer RA. Prebiotics Reduce Body Fat and Alter Intestinal Microbiota in Children Who Are Overweight or With Obesity. Gastroenterology. 2017 Sep;153(3):711-722. doi: 10.1053/j.gastro.2017.05.055. Epub 2017 Jun 5. PMID: 28596023.
“Prebiotics vs. Probiotics: What’s the Difference?” healthessentials. Cleveland Clinic. https://health.clevelandclinic.org/prebiotics-vs-probiotics-whats-the-difference/. Accessed 13 September 2021.
Palken J. Prebiotics: what, where, and how to get them. Center for Applied Nutrition. UMass Chan. https://www.umassmed.edu/nutrition/ibd/ask-Nutritionist/prebiotics-what-where-and-how-to-get-them/.
Prebiotics
Yu Feng Lin & Fawziya Twam
Prebiotics, non-digestible dietary compounds, stand as crucial players in nourishing beneficial gut bacteria, ultimately contributing to overall health. Their influence spans across multiple facets, encompassing improvements in gastrointestinal conditions, impacts on skin health, cardiovascular well-being, calcium absorption, and potential effects on mental health. Prebiotics serve as essential components in the delicate balance of the gut microbiota. They possess the unique ability to selectively nourish beneficial bacterial strains, including Bifidobacteria and Lactobacilli, while concurrently inhibiting the proliferation of harmful pathogens. This selective nutritional support plays a pivotal role in fostering and sustaining a harmonious gut environment, a cornerstone of optimal health.
Prebiotics have also been subjects of research aimed at managing gastrointestinal conditions, such as Irritable Bowel Syndrome (IBS) and Crohn's Disease. While certain studies suggest improvements in IBS symptoms with prebiotic consumption, the results remain heterogeneous due to variations in prebiotic types and doses. Conversely, regarding Crohn's Disease, the effects of prebiotics are less conclusive, with some studies failing to demonstrate significant clinical benefits. Colorectal cancer, a global health concern of substantial magnitude, is another area where prebiotics hold potential. Particularly, prebiotics that contribute to the production of butyrate exhibit promise in safeguarding against colorectal cancer risk and progression. They have the capacity to induce apoptosis in cancer cells and enhance the integrity of the epithelial barrier, contributing to a defense mechanism against this malignancy.
Prebiotics like FOS and GOS emerge as potential tools in preventing necrotizing enterocolitis (NEC), a severe condition predominantly affecting premature neonates. These prebiotics facilitate the growth of beneficial Bifidobacteria and enhance feeding tolerance, though further research is essential to confirm their effectiveness in reducing the risk of NEC. Immunity receives a significant boost from prebiotics as they elevate the population of protective microorganisms, simultaneously reducing pathogen colonization. These compounds also induce the expression of immune molecules, particularly cytokines, with maternal prebiotic metabolites even impacting the development of the fetal immune system.
The intricate "gut-brain axis" connects the gut and brain through neural, endocrine, and immune pathways, and prebiotics wield the potential to influence brain function. This can have implications for mood, memory, learning, and psychiatric disorders, all mediated by shifts in the composition and activity of the gut microbiota. Additionally, prebiotics have shown potential therapeutic applications in specific health conditions, such as autism and hepatic encephalopathy. Research suggests that prebiotics may impact autism by altering gut microbiota composition and neurotransmitter production, but further investigation is warranted. In the case of hepatic encephalopathy, lactulose, a prebiotic, effectively treats the condition by reducing ammonia levels and inhibiting glutaminase.
Shifting focus to skin health, prebiotics are also relevant. They offer potential benefits in reducing the risk and severity of skin conditions like atopic dermatitis, enhance skin barrier function, and counteract the effects of harmful phenols on the skin.
Cardiovascular health benefits from prebiotics as well, with the potential to reduce the risk of cardiovascular diseases (CVD) through the lowering of inflammation and improvement of lipid profiles. Nevertheless, their impact on cholesterol levels remains inconsistent, and certain short-chain fatty acids (SCFAs) produced by prebiotics may have negative implications. When it comes to calcium absorption, prebiotics may exert influence, albeit with variability depending on the specific type. While some prebiotics, such as lactulose, TOS, and inulin + oligofructose, have demonstrated the ability to enhance calcium absorption, others, like GOS or FOS, do not yield the same effect.
In terms of safety, prebiotics are generally considered safe for consumption, yet they can induce mild side effects like osmotic diarrhea, bloating, and flatulence. The severity of these side effects may hinge on factors like chain length and dosage, with low and high doses potentially resulting in mild to moderate side effects. Therefore, it is imperative to adhere to recommended therapeutic dose ranges when utilizing prebiotics. As for the future trajectory of prebiotic research, it holds immense promise for improving human health, but a more profound understanding of their mechanisms and substantiation of health claims is imperative. Rigorously designed clinical trials and genomics investigations will play pivotal roles in this endeavor. Furthermore, the concept of formulating population-specific prebiotics, tailored to the distinct gut microbiota of local communities, presents an intriguing standardized approach to enhancing health.
Prebiotics emerge as versatile agents impacting a spectrum of health domains, ranging from the equilibrium of gut microbiota to potential influences on diverse health conditions. Although further research is indispensable to comprehensively comprehend their safety and effectiveness in varied contexts, prebiotics undeniably wield considerable potential in advancing overall well-being.
References:
Davani-Davari D, Negahdaripour M, Karimzadeh I, et al. Prebiotics: Definition, Types, Sources, Mechanisms, and Clinical Applications. Foods. 2019;8(3):92. Published 2019 Mar 9. doi:10.3390/foods8030092
Guarino MPL, Altomare A, Emerenziani S, et al. Mechanisms of Action of Prebiotics and Their Effects on Gastro-Intestinal Disorders in Adults. Nutrients. 2020;12(4):1037. Published 2020 Apr 9. doi:10.3390/nu12041037