When you read the title of this article, you probably frowned and thought to yourself, ‘How can my gut and heart possibly be linked? They are in very different parts of my body!’ You will be surprised… More and more research is emerging about how the little organisms in our gut influence our health. Let’s see what it says about how they influence our hearts.
WHAT IS THE GUT MICROBIOTA?
The human intestine houses trillions of microorganisms, most of which are bacteria and viruses that are considered harmless. This can be a daunting thought, especially when you think they can contribute up to 2kg of your body weight!1. These microbes work with the body’s defences and immune system to protect us from bacteria and viruses that cause diseases. They also provide essential vitamins and aid in extracting energy and nutrients from our food2.
Furthermore, the gut microbiota produces a wide range of compounds that may be carried in the blood and distributed to different parts of the body, where they can influence certain important processes3.
HOW THE GUT MICROBIOTA IS LINKED TO HEALTH?
It is strange to think that these little microbes play a role in protecting us from disease. So, where does it go wrong? The answer is dysbiosis…
Dysbiosis occurs when there are abnormal changes in the composition of the intestinal microbiota3,4. For quite some time, we have known that dysbiosis contributes to the development of certain diseases involving altered intestinal health3. However, only fairly recently have we come to realise that dysbiosis plays an intricate role in a wide range of diseases that do not involve the intestines.
An abnormal gut microbiota composition has been linked to obesity, type 1 and type 2 diabetes, non-alcoholic fatty liver disease, certain cancers and autoimmune diseases5,6. This is due to the influence that the microbiota has on our metabolic pathways. For example, the types of bacteria that are found in the gut of lean individuals differ from those found in obese individuals5,6. This illustrates the role they could play in our gaining unwanted weight and struggling to shake it off.
DIET AND THE GUT MICROBIOTA
What we eat affects the microbiota that lives in our intestines, as well as its by-products7. A few studies have shown that a diet that is high in fat and animal protein can drastically change the gut microbiota, reducing the number of bacteria that are considered beneficial to our health, and increasing the amount of bacteria that produce harmful by-products7. Beyond altering the gut microbiota, we know that red meat consumption is also associated with an increased cardiovascular disease (CVD) risk.
Studies show that the more dietary fibre you consume, the lower your CVD risk7. Fermentable fibres, especially prebiotics (fibre that can convey various health benefits), increase the abundance of health-promoting bacteria. The fermentation of these fibres leads to the production of Short Chain Fatty Acids (SCFAs)7. SCFAs play a number of different roles in the body, one of which involves influencing different hormones which help to control satiety and food intake and maintain the gut barrier function. Maintaining this barrier function prevents the uptake of inflammatory compounds that can lead to chronic low-grade inflammation associated with obesity and CVD7.
Additionally, plant polyphenols (naturally occurring compounds found in plant-based foods) can inhibit the growth of certain gut bacteria and promote the growth of others. It is better to consume polyphenols and fermentable fibres as part of your diet, than it is to take supplements. They work together with food to provide health benefits that are linked to reduced CVD risk7.
LINK BETWEEN THE GUT AND THE HEART
So now that we know that what we eat influences our gut microbiota and that dysbiosis can contribute to the development of various diseases, what is the link with our heart specifically?
It lies in a study by Wang et al., where they found a pathway that links dietary fat intake, our gut microflora and atherosclerosis6. It was found that Trimethylamine-N-oxide (what a mouthful!), which we will refer to as TMAO, is linked to an increased risk of heart attacks, strokes and death. TMAO is a by-product from the digestion of certain nutrients found in foods that are rich in cholesterol and fat: red meat, liver and egg yolk. Elevated levels of TMAO are positively associated with the formation of plaque in our blood vessels, which increases one’s risk of future cardiac events5,6.
It is now also recognised that the gut contributes to the development of heart failure and the complications associated with it5. During heart failure, the gut wall is impaired due to an overgrowth of bacteria and decreased host defence. This leads to unwanted bacteria getting into the blood and releasing toxins, which results in inflammation5.
Vegans and vegetarians have lower TMAO levels than omnivores. This is due to the fact that they exclude the foods that are rich in the nutrients from which TMAO is derived3. The types of microbiota that are found in vegans and vegetarians also differ from those found in omnivores. Thus the diet followed by omnivores promotes the growth of certain microbiotas that would prefer to feed on the nutrients that result in the production of TMAO3.
HOW CAN I IMPROVE MY MICROBIAL COMMUNITY?
So how can I improve my microbial community to achieve optimal health and hopefully prevent future diseases, including heart disease?
To start the process, it might be wise to provide your body with probiotics (good bacteria) that are known to result in heart health benefits. This is very strain-specific. For example, some strains provide immune modulation, whereas others can lower cholesterol, even though these bacteria may belong to the same species7. It is therefore necessary to select the right probiotic strain to help lower CVD risk.
You then need to provide the bacteria with the correct food. So you are not eating for one, but for a trillion! You need to factor in what your gut microbiota likes to eat and ensure that you include these foods in your diet. Probiotics feed on prebiotics and fermentable fibres, so by including them in your diet, you promote the growth of beneficial bacteria in your gut. You can get these fibres from fruits, vegetables and whole-grains.
Foods known to be protective against CVD – such as fruits, vegetables and whole grain cereals that are rich in fermentable fibres, prebiotics and polyphenols – may provide their protective effect, at least in part, through their influence on the gut microbiota. On the other hand, a diet that is high in red meat and fat and low in fibre is associated with decreased microbiota diversity, increased unwanted bacteria as well as increased production of TMAO, which is known to be toxic for heart function7. So the way to man’s heart is indeed through his gut!
WHERE DOES FUTURELIFE® FIT IN?
FUTURELIFE® Bran Flakes and Barley with Probiotic Capsulescomes with 10 capsules of HOWARU® Premium Probiotics per 460g/910g box. HOWARU® Premium Probiotics is a blend of clinically studied probiotics that has been scientifically formulated to contain two of the most beneficial probiotic strains, namely HOWARU® Lactobacillus acidophilus and HOWARU® Bifidobacterium lactic. The product itself has wheat bran as its base. Wheat bran also has prebiotic activity and results in the production of short chain fatty acids. Most of our other FUTURELIFE® products also contain inulin, which is a prebiotic. Apart from that our products are low-moderate in
- [Online] http://www.gutmicrobiotaforhealth.com/en/about-gut-microbiota-info/.
- Dysbiosis of the gut microbiota in disease. Simon Carding, Kristin Verbeke, Daniel T. Vipond, Bernard M. Corfe and Lauren J. Owen. s.l. : Microbial Ecology in Health and Disease, 2015, Vol. 26.
- The contributory role of gut microbiota in cardiovascular disease. Hazen, W.H. Wilson Tang and Stanley L. 10, s.l. : The Journal of Clinical Investigation, 2014, Vol. 124.
- Linking the gut microbiota to human health. Guarner, Virginia Robles Alonso and Francisco. s.l. : British Journal of Nutrition, 2013, Vol. 109.
- Prognostic Value of Elevated Levels of Intestinal Microbe-Generated Metabolite Trimethylamine-N-Oxide in Patients With Heart Failure. H.Wilson Tang, Zeneng Wang, Yiying Fan, Bruce Levison, Jennie E. Hazen, Lillian M. Donahue, Yuping Wu, Stanley L. Hazen. 18, s.l. : Journal of the American College of Cardiology, 2014, Vol. 64.
- The Heart and the Gut. Rosano, Gerhard Rogler and Giuseppe. s.l. : European Heart Journal, 2014, Vol. 35.
- ‘The way to a man’s heart is through his gut microbiota’ – dietary pro- and prebiotics for the management of cardiovascular risk. Kieran M. Tuohy, Francesca Fava and Roberto Viola. : Proceedings of the Nutrition Society, 2014, Vol. 73.