Revealing the master of digestion – gut microbiome
Here’s a quick quiz question for you: What is the body’s most important organ of digestion?
Did you say the stomach? Or perhaps the liver? Maybe you said the intestines… and you would be close to the right answer; but not quite on top of it.
That’s because the greatest digestive organ of all time is….
The British Medical Journal calls the human microbiome “an organ in its own right”
As a well-respected journal, the BMJ calling the gut microbiome an organ is something you can trust1. Of course, it sounds strange to call a colony of bacteria, fungus, yeast, viruses and other microorganisms an organ, but you’ll see why as you continue to read.
Let’s look more closely at the microbiome; what it is, what it does, and how it can either work for you… or against you.
A complex system, living in your digestive tract
The authors of a 2017 BMJ review study explains that the microbiome that is far more complex than human DNA. Large-scale projects propose that there are more than 3 billion possible unique gene sequences that may come from these microorganisms which, when you compare it to the human genome of 23 000, shows just how significant this colony is2. And when you look at it that way, you can begin to see what it has such a profound influence on a person’s health.
At the very basic level, this microbiome is involved in the immune response of the body. From the moment you are born, these microorganisms play a fundamental role in your immune system. They are involved in its conception as well as training and function throughout your life. This interaction between the immune system and the microorganisms is what evolves into a relationship that ensures processes that take place within the digestive tract are beneficial to the host: you and your wellbeing. It’s this relationship that allows the body to recognize and target foreign invading pathogens, as well as maintain a certain level of defense against anything harmful that may attack the body3.
Besides this crucial role in immunity, the microbiome plays other significant functions in human health. One of those is nutrition.
Without gut bacteria, you would be deficient in a number of crucial compounds your body needs to thrive and survive. During digestion, they help to break down leftover food particles and, as they ferment them, the microorganisms release compounds that are beneficial to your body. For example, vitamin K and B12 are obtained from certain species of bacteria. Both are critical, as vitamin K is involved in maintaining the fluidity of your blood, preventing clotting, while vitamin B12 is important in a number of body systems, including energy homeostasis.
Another significant contribution of your gut microorganisms, is their production of short chain fatty acids, or SCFAs. When they digest dietary fibre, these SCFAs are made, which the body uses to maintain the health of your intestinal lining and provides the food these cells within the digestive tracts need to function. They’re also responsible for reducing your risk of type 2 diabetes, heart disease, obesity, and other chronic medical conditions4,5,6.
You can see how important it is to maintain a healthy microbiome, can’t you… Unfortunately, it has become more and more difficult to do in our modern-day society.
The fight to keep your gut health intact
Processed foods, preservatives, hydrogenated oil, refined fats and sugar, low-fibre diets, food-borne chemicals…. The list goes on. There are so many factors we need to watch out for when it comes to keeping our microbiome healthy and working for us instead of against us. These food items chip away at the integrity of your microbiome, leaving you vulnerable to dramatic imbalances within your digestive tract and at an increased risk of chronic disease7,8.
It’s the way we live that are drastically changing our gut health and leaving us with less diverse gut microorganisms, which often favour more harmful bacteria, which contribute less to our health and wellbeing.
The Yanomami people, who live in the Venezuelan rainforest, have been found to have one of the most diverse gut microorganism populations ever seen. They have little – if any – access to this Westernized way of living, and their traditional way of life and their diet has been followed for more than 11,000 years. What’s more, is their non-existent exposure to antibiotics, which means they have largely held onto the bacteria they developed as infants and children9.
Their diet follows that of the typical hunter-gatherer. Hunting accounts for only 10% of their food, which means 90% of what they eat comes from gathering, i.e. plant-material10. The significance of this lies in the dietary fibre.
Feeding your microbiome
Fibre has one of the most significant impacts on the gut. Of course, it helps to move things along, but it also provides an important food source for your microbiome. The Yanomami have a high intake of dietary fibre, where the cassava – a potato-like root vegetable – makes up a large portion of their diet. It’s nutrient-rich, and provides a type of resistant starch as well as prebiotic fibre that provides food to their gut bacteria, contributing to the diversity and healthy they maintain11.
Today, in the modern-world, many of us eat far too little fibre. Instead of getting the daily required amount of close to 30g, some of us are hardly ingesting half of that on a day-to-day basis12. One of the easiest ways to boost your gut – and overall – health, is to increase your fibre intake. Root vegetables similar to cassava are sweet and regular potatoes, carrots, beets, and yacon root. What’s interesting about yacon root, is that it too, is native to South America, this time in the Andean regions, and is typical of the traditional diet in these areas. Studies on supplementation with the fibre it contains, has shown to be an effective way to increase dietary fibre to both prevent and treat chronic diseases13. Traditionally, it has long been used in folk medicine to treat a number of ailments involving the digestive tract14. Other fibre-rich foods include all types of vegetables and fruit, whole grains like barley and brown rice, nuts, seeds and legumes.
From reducing your intake of refined, processed, convenience and chemically-laden foods, to supplementing with a variety of probiotics and feeding them with good quality fibre, there is a way you can take back control of your microbiome. It’s the only way to keep it in balance, and to keep the critters in your digestive tract contributing to your health, instead of being the reason it’s being stripped away.
- Amon P, Sanderson I. Arch Dis Child Educ Pract Ed 2017;102:258–261.
- Qin J , Li R , Raes J , et al . A human gut microbial gene catalogue established by metagenomic sequencing. Nature 2010;464:59–65.
- Belkaid, Y, Hand, T. Role of the Microbiota in Immunity and inflammation. Cell. 2014 Mar 27; 157(1): 121–141.
- Chambers, E., et al. Role of Gut Microbiota-Generated Short-Chain Fatty Acids in Metabolic and Cardiovascular Health. Curr Nutr Rep. 2018; 7(4): 198–206.
- Tan, J., et al. The role of short-chain fatty acids in health and disease. Adv Immunol. 2014;121:91-119.
- RIos-Covian, D., et al. Intestinal Short Chain Fatty Acids and their Link with Diet and Human Health. Front Microbiol. 2016 Feb 17;7:185.
- Brüssow H, Parkinson SJ. You are what you eat. Nat Biotechnol. 2014 Mar; 32(3):243-5.
- Louis P, Hold GL, Flint HJ. The gut microbiota, bacterial metabolites and colorectal cancer. Nat Rev Microbiol. 2014 Oct; 12(10):661-72.
- Clemente, J., et al. The microbiome of uncontacted Amerindians. Science Advances 17 Apr 2015: Vol. 1, no. 3, e1500183
- Survival International. The Yanomami.
- Osundahunsi, O., et al. Prebiotic effects of cassava fibre as an ingredient in cracker-like products. Food Funct. 2012 Feb;3(2):159-63.
- Martens, E. Fibre for the future. Nature volume 529, pages 158–159 (14 January 2016).
- Caetano, B., et al. Yacon (Smallanthus sonchifolius) as a Food Supplement: Health-Promoting Benefits of Fructooligosaccharides. Nutrients. 2016 Jul; 8(7): 436.
- Delgado GT, Tamashiro WM, Maróstica Junior MR, Pastore GM. Yacon (Smallanthus sonchifolius): a functional food. Plant Foods Hum Nutr. 2013 Sep; 68(3):222-8.