Gut Microbiota and Microbiome

How to Take Good Care of Them

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The relationship between your gut health and overall health is crystal clear: when you take good care of your gut microbiota, they take good care of you.

Gut microbiota or gut flora is the collection of microorganisms that live in your digestive tract. They’re predominantly made up of bacteria and to a lesser extent, viruses and fungi. In this article, we’ll focus on how to take good care of the beneficial bacteria in your gut. When we say gut microbiome, we’re referring to the total genetic material of your gut microbiota. The research spotlight is now on gut microbiome because of its enormous potential in explaining how some diseases develop (pathophysiology) and how to formulate treatment strategies against these diseases.

Our gut microbiota has several functions that benefit our overall health and this is the primary reason we need to take good care of them. There are three essential things you should keep in mind when considering your gut health:

What factors can negatively affect your gut microbiota
What happens to your health when your gut microbiota is in a state of imbalance (called dysbiosis)
How can you support your gut microbiota

What factors can negatively affect your gut microbiota?

Diet. The kind of food you consume can have a tremendous impact on your gut microbiota. The Western diet known for its high fat and low fibre content is associated with decreased beneficial bacteria, specifically the Bifidobacterium and Eubacterium species. A Mediterranean diet is an example of a high-fibre diet that increases the total number of beneficial bacteria in your gut.
Age. After the age of 70, your immune system starts to decline, and changes in digestion, physical activity, and nutrient intake can affect gut microbiota composition. The imbalance can lead to a proinflammatory state associated with other health issues like cancer development and malnutrition.
Drug/medication use. Some medications like proton pump inhibitors and antibiotics can change the gut microbial composition. Antibiotic use can reduce the diversity of bacterial groups which can be prolonged. Proton pump inhibitors reduce gastrointestinal tract acidity and both scenarios can promote the overgrowth of harmful bacteria.
Drinking alcohol and tobacco use. A study that appeared in the American Journal of Physiology Gastrointestinal and Liver Physiology has noted that chronic alcoholism is linked with changes in the gut microbial composition that may favour the presence of bacterial toxins in the blood. Similarly, smoking has also been connected to changes in the composition of your gut microbiota.
Exposure to harmful bacteria. Colonisation by harmful bacteria can initiate inflammation in your gastrointestinal tract. The inflammation can then disrupt the normal balance between microbial communities leading to altered functions. These harmful bacteria can also outcompete your gut microbiota during these inflammatory states.
Stress and anxiety. Anxiety and psychological stress can affect intestinal motility (constipation or diarrhoea), secretion of hormones and enzymes, the permeability of your intestinal lining, and sensory perception of your digestive organs. Stress and anxiety are like natural disasters (earthquake or storm) on the gut microbiota and after such conditions, the composition of gut microbiota is negatively affected.
Geography, particularly urbanisation, has a strong impact on the diversity of your gut microbiota. Exposure to pollution and unhygienic status may also add burden to urbanisation. All these factors prohibit the diversity of your gut microbiota.
Your sleep schedule and circadian rhythm can also alter your gut microbiota. Irregular timing of sleep, eating times, and lack of relaxation can lead to an imbalance in microbial composition.

What happens to your health when your gut microbiota is in a state of imbalance? Is it linked to the development or worsening of particular diseases?

Thanks to research studies, associations have been established between gut microbiota and some diseases. It’s not certain whether these diseases cause the imbalance of the microbial population or the other way around, with ongoing research underway. So, for now, we will settle with ‘they just have a connection’, and will elaborate on ones that have caught much attention and interest in recent years.

Allergic diseases like atopic asthma, rhinitis, atopic eczema, and food allergies have seen increases in the number of cases in recent years. Some experts attribute this to the hygiene hypothesis.

The hygiene hypothesis can be explained when a baby is exposed to fewer varieties and quantities of microorganisms during infancy resulting in a lesser microbial challenge and weak immune systems. The gut microbiota is one of the body parts where an infant can be exposed, adequately process the response, and initiate a proper immunological reaction. Because of the hygiene hypothesis, being too clean may inadequately expose your child and develop a poorly educated immune system.
People who are obese or with diabetes mellitus type 2 manifest a state of functional imbalance (dysbiosis) in their gut microbiota. It was also observed that there are certain groups of opportunistic harmful bacteria present in various concentrations in the gut.
People with IBD (inflammatory bowel disease) have reduced numbers of Firmicutes bacteria. Firmicutes bacteria are vital producers of SCFAs (short-chain fatty acids), which have potent anti-inflammatory properties.
The exact cause of IBS (irritable bowel syndrome) is unknown but is believed to be multifactorial. Infection (harmful bacteria) and inflammation are some of these factors. Like the other diseases mentioned here, people with IBS exhibit altered composition of gut microbiota and deranged colonic fermentation which could have an essential role in the development of IBS symptoms.
Your gut and liver share a special relationship called the gut-liver axis. Smack in the middle of that relationship is your gut microbiota. Substances produced by beneficial bacteria are metabolised by the liver for cytokine production and Kupffer cell (immune cells that protect the liver) activity. Any significant liver disease (cirrhosis, hepatitis) can affect the microbial population and diversity in your gut. Likewise, unhealthy growth of pathogenic bacteria may cripple some of your liver functions.
Colon cancer patients were also found to have less butyrate-producing bacteria in their gut microbiota. Butyrate is a short-chain fatty acid needed by other beneficial bacteria to help control inflammation and possibly prevent a leaky gut. A healthy gut microbiota will undoubtedly contribute to the prevention of cancer in your digestive tract.

Tips on How to Support Your Gut Microbiota

Dietary adjustments:

Dietary fibre has been proven to be therapeutic and preventative for many intestinal disorders, cardiovascular disorders, obesity, and diabetes mellitus type 2. Your gut microbiota breaks down (fermentation) undigested fibre to organic acids that provide energy for them and nutrients for the lining of your intestines. Fibre also adds to faecal mass (the bulk of your poop), dilutes toxins, reduces mechanical movement of your intestines, decreases transit time, and increases bowel movement frequency. Try to consume between 25 to 30 g of fibre every day.
Resistant starch, like those found in raw potatoes, green bananas, legumes, grains, seeds, etc., acts as a prebiotic.

Your gut microbiota converts starch like fibre to short-chain fatty acids that support their growth and proliferation. Focus on increasing your resistant starch and fibre intake while limiting the consumption of other forms of carbohydrates.

Too much protein from processed red meat is associated with higher levels of protein fermentation products from your gut microbiota. These end products can contribute to the development of cancer. The quality and quantity of your protein intake are key.

Lifestyle changes. The way you live and take care of yourself undoubtedly has a massive impact on your gut microbiota.

According to a study published in the Journal of Exercise and Sport Science Reviews in April 2019, it’s theorised that the beneficial effects of exercise on your brain are mediated by your gut microbiota. Exercise increases gut microbiota activity to produce butyrate, a short-chain fatty acid, which has anti-depressant activity as well as activating your brain’s immune cells (called microglial cells).
Stop smoking. Smoking increases your risk for digestive disorders like developing gallstones, digestive tract cancers, peptic ulcers, and heartburn. All these digestive disorders disrupt the health of your gut microbiota.
Stress lowers the microbial population of an essential bacteria, Lactobacillus. It also contributes to the development of irritable bowel syndrome by increasing intestinal activity (motility). We can’t live without stress, though, so we should learn to manage it and relax every once in a while.
Lose the extra weight. Obesity leads to an imbalance in microbial populations and the increase of bacteria that produce proinflammatory substances.
Where you live also has an impact on your gut health and different members of your gut microbiota. Whenever you can, aim for less polluted, hygienic, less urbanised (better yet, choose rural) areas.
Keep a consistent sleep schedule.

Supplements that may help:

Ginger has been shown to have anti-inflammatory effects and may help decrease inflammation in your gastrointestinal tract when there’s an imbalance in microbial composition. Let’s not forget that it also has antioxidant, antiulcer, and anticancer properties.
Chamomile tea and extracts also have an anti-inflammatory effect in addition to its ability to reduce stomach acid to prevent the growth of harmful bacteria.
Peppermint tea and extracts have a relaxing effect on your digestive tract. This may benefit your gut microbiota by helping maintain the balance and composition of your gut microbiota. Increased gut activity disrupts their distribution.
Bitter herbs, such as gentian, dandelion, wormwood, burdock, parsley, horseradish, mugwort, coriander, mint and horehound, act as digestive aids and increase the secretion of digestive enzymes.
A 2018 study published in the Biochemical and Biophysical Research Communications Journal has shown results suggesting that pancreatic enzyme replacement therapy promotes colonisation and proliferation of beneficial gut bacteria. People who can’t produce enough digestive enzymes because of certain medical conditions may benefit from supplementing with digestive enzymes to help their gut microbiota grow in numbers.
Both prebiotics and probiotics have been documented to support gut microbiota (see below because they both deserve special mention).

How do probiotics help your gut microbiota?

We all know probiotics help your gut microbiota. They can be found in fermented foods like kefir, kombucha, yoghurt, sauerkraut, tempeh, kimchi, miso, sourdough bread, pickles, and some cheeses. They can also be supplied in supplement form. Most common probiotics contain Bifidobacterium and Lactobacillus bacteria.

Probiotics help your gut microbiota by:

Direct competition with harmful bacteria for receptors and nutrients.
Increasing the production of antibodies at the gut level.
Strengthening the lining of your gastrointestinal tract, thereby preventing the entrance of harmful bacteria into your body.

What is the role of prebiotics in supporting your gut microbiota?

Prebiotics are dietary substances that promote the proliferation and increase the activity of beneficial bacteria residing in your colon. The more you feed them with the good stuff (prebiotics), the healthier and more active they become.
To qualify as a prebiotic, a substance or food ingredient has to:

Survive digestion in the small intestine
Be fermented in the colon to alter its activity
Provide demonstrable benefit for the host or consumer.

All well-known prebiotics to date are:

Carbohydrates

Lactobacillus

Bifidobacterium

These food ingredients are naturally found in fruits, vegetables, and cereals.

So, there you have it, factors that can negatively affect your gut microbiota, what happens when there’s dysbiosis, and tips on how to support your gut microbiota. Keeping these three things in check will help you take good care of your gut microbiota and promote a healthy gut.