Understanding
Digestive Health

What is digestive health?

Turning the food that we eat into the nutrients and energy we need to survive is the most obvious (and an extremely necessary) function of the digestive system, but it is only possible with a healthy gut.

Over the last few decades, the research done on the role of our digestive systems has developed dramatically. Previously, our gut was seen simply as a long hollow tube that food passed through, starting at the mouth and ending at the anus. Evidence now shows that the human gut is in fact more complex than previously assumed, with various links made between the digestive system and other organ systems in our bodies, like the skin, endocrine system, immune system, and the central nervous system. Having a healthy gut has been linked to many health benefits, including a boosted immune function, reduced risk of some diseases, healthier skin, improved digestion, and even weight loss.

The gut microbiome

The 100 trillion microorganisms (or microbes) living in the human gastrointestinal tract are referred to as the “gut microbiome”. This microbiome is now seen as a virtual organ of the body and is made up of different types of microbes – mostly bacteria, but it also includes viruses, protozoa, and fungi. Generally, when one thinks about bacteria, it is usually in relation to infection or disease, but there are also good bacteria which are necessary and potentially beneficial to having a healthy mind and body. These bacteria are called normal flora. People have around 500 different species of bacteria, comprising almost 2 million genes, living in their gut.  

Humans have had microbes in their guts for millions of years and it turns out that most of our gut microbiome has been evolving with us. What this tells us is that our microbiomes are most likely inherited, but additional research shows that it is also greatly influenced by environmental factors like diet. Every person’s microbiome is different, with no two people having the same microbiome – even twins have different combinations of microbes.

The moment you are born, your gut microbiome has an impact on your body. As the microbiome grows, it starts to contain a variety of different microbes and continues to influence your body in various ways. This includes being able to digest breastmilk appropriately as a new-born, and the ability of the growing body to respond to infection and influence brain function. As a result, the gut microbiome plays an important role in our essential bodily functions and overall health.

Diversity, that is, a wide variety of good bacteria, represents a healthy gut. Having a species-rich gut ecosystem means that the gut can enhance our immune system, help our mental wellbeing, and assist with other bodily processes, since it is more robust against environmental influences. Interesting to note that around 70 percent of the immune system is found in the gut, meaning that it is essential that our digestive systems are well taken care of in order to manage the various health challenges that we may face. Conversely, lower bacterial diversity has been seen in people with various chronic conditions like type II diabetes, high cholesterol, obesity, atopic eczema, and inflammatory bowel disease.

Apart from the gut, beneficial microbes can be found in various other parts of your body. Other parts of your body that house normal flora are those locations that are in contact with the external environment, such as your mouth, urinary tract, skin, lungs, and vagina.

How do gut flora help us?

The main function of normal flora is to maintain a healthy balance between the good and harmful bacteria in the body. This balancing act of good and bad bacteria occurs continuously inside our bodies.

Apart from keeping harmful bacteria in check, the normal flora in the gut keeps us healthy by manufacturing vitamins, such as vitamin K as well as some of the B vitamins. Furthermore, these gut microbes convert fibres into short-chain fatty acids like butyrate, propionate, and acetate that not only feed the gut wall, but also perform many other metabolic functions. Apart from being the main energy source for the cells lining the colon, butyrate can also help the immune system to destroy cancerous colon cells, while it also plays an important role in glucose and energy metabolism. In addition, it helps to maintain oxygen balance in the gut assisting with the prevention of microbial imbalance. Propionate plays a role in glucose homeostasis in the liver and also helps to send satiety signals, while acetate (the most abundant short-chain fatty acid) is essential to the growth of other bacteria. It is transported in the blood stream to peripheral tissues where it is used in cholesterol metabolism. Acetate is also thought to assist with central appetite regulation.

These short-chain fatty acids further stimulate the immune system, and this may help prevent unwanted microorganisms or other substances from entering the body and provoking an immune response.

Good bacteria also help to control inflammation, which is a leading driver of many diseases.

Good food choices to support gut health

Probiotics

Probiotics are living microbes that, when ingested, provide a health benefit. These live microorganisms, usually bacteria and yeasts, can be found in some foods but can also be taken as supplements. By colonising your gut with good microbes, probiotics benefit us in various ways. This includes helping to keep the balance of “good” and “bad” bacteria in your gut and reducing the risk of diarrhoea that can be caused by taking antibiotics for a bacterial infection.

There are various bacterial species that function as probiotics, the most common being Lactobacillus and Bifidobacteria. Additional common strains are Streptococcus, Enterococcus, Escherichia, and Bacillus. Saccharomyces boulardii is a yeast that is a common constituent of some probiotics.

It is not always necessary to take additional probiotics if you eat a well-balanced diet. As this is not always possible, one can also take probiotic supplements to assist with this process. These supplements come in various forms including drinks, powders, capsules, or pills. There are so many different options and it can be quite overwhelming when trying to decide what to take. Consulting your healthcare provider and asking for suggestions would be a good place to start. There are also certain types of foods that contain probiotics. These are foods that are prepared by bacterial fermentation and include:

  • Yoghurt
  • Cottage cheese
  • Sourdough bread
  • Kombucha
  • Kimchi
  • Sauerkraut
  • Tempeh
  • Miso soup

Can children take probiotics?

Children can also take probiotics, but it is always important to discuss this with a trusted healthcare professional. A safe way to introduce probiotics into a child’s diet is through food. For example, including yoghurt or cottage cheese into a balanced diet can assist with adding good bacteria to your child’s gut. There are also probiotic supplements which are available for children.

Prebiotics and synbiotics

Prebiotics are, in essence, foods that help probiotics grow. These are usually high-fibre foods like whole grains (e.g., flaxseed and oats), green vegetables (including spinach, asparagus, and leeks), and well as different types of fruit (such as bananas, apples, and berries).

These foods contain carbohydrates that your body cannot digest. These indigestible carbs then go into your gut where they act like food to help the “good” bacteria grow.

Ideally, getting prebiotics from whole foods compared to supplements is a better option since these foods also contain vitamins, minerals, and antioxidants. Prebiotic supplements are also available at pharmacies and health shops. The term “synbiotic” is used when a supplement contains both a prebiotic and a probiotic.

Simple things to ensure gut health

Besides a well-balanced diet and taking supplements where needed, there are a few other simple things you can do to help your digestive system:

  • Get at least 7 – 8 hours of sleep per night.
  • Include activities into your daily routine that reduce stress, e.g., meditation, walking, reading, and reducing your caffeine intake.
  • Eat slowly. This gives your gut time to fully digest your food and absorb the important nutrients your body needs.
  • Drink plenty of water.
  • Be mindful of how your body responds to different types of food. Some abdominal symptoms like cramping, bloating, nausea, and heartburn can be associated with being intolerant of certain foods.
  • Changing simple things in your diet like reducing the amount of processed foods or foods with high sugar or high fat contents can contribute positively to a healthy gut.

Diagnosing a gut health problem

Now that we know what a healthy gut needs to thrive, what are some of the symptoms people may experience when their guts are not functioning properly?

Everyone at some time or another will experience digestive problems. When your gut is not able to process food and eliminate waste effectively, you may experience troubles like constipation, bloating, nausea, gas, loose stools, abdominal pain, or heartburn. Many of these symptoms occur commonly and are not necessarily a cause for concern. It is, however, important to contact your healthcare provider should any of these symptoms occur repeatedly or if these symptoms persist for longer than 2 weeks, as this may suggest that there is an underlying problem.

When to see a doctor

There are certain gut symptoms that you should alert your healthcare provider to as soon as possible. These include:

  • Stool changes such as:
    • A change in stool colour – this can be if your stools become a deep red, burgundy or black (especially if there is also a noticeable odour), or if there is fresh blood in your stool. This also applies if the colour of your stools is very pale, especially if it goes hand in hand with your urine turning dark, as this may be indicative of a bile duct or liver problem.

Small amounts of bright red blood on stool or toilet paper are mostly indicative of haemorrhoids (or piles) or a scratch in the rectal area. Generally, these should not be a cause for concern, unless there are more than just a few streaks of blood visible in the stool or on the toilet paper or if there is bloody diarrhoea. The latter calls for immediate medical attention.

  • A change in the consistency of your stools –
    • Constipation is usually characterised by dry, hard stools. If constipation should persist for more than 2 weeks, you must notify your healthcare provider.
    • Also notify your healthcare provider if mucus and fluid leak out of the rectum as this may be indicative of stool that has become lodged (impacted) in the rectum.
    • Diarrhoea is characterised by loose and watery stools, and it occurs quite commonly; however, if diarrhoea is accompanied by the following symptoms, it may indicate a serious problem: severe stomach pain or discomfort not relieved by passing stool or gas, fever, chills, vomiting, or fainting. It is also important to contact a doctor without further delay if the diarrhoea lasts for more than 2 days in an adult, or more than 1 day in a child younger than 3 years or more than 8 hours in an infant under 6 months.

Those that have recently taken antibiotics, the elderly, recently hospitalised, pregnant women, or people with compromised immune systems should also immediately alert their doctor if they develop diarrhoea.

  • A change in the frequency of your bowel movement – this differs greatly from person to person, so knowing what is your “normal” will help you identify when it has been too long since your last bowel movement. Neither constipation nor diarrhoea should last for longer than 2 weeks following which a doctor must be consulted.
  • Sudden, unexplained urges to pass stool
  • Weight loss without a good reason
  • Severe vomiting
  • Severe stomach pain
  • Trouble swallowing food or experiencing pain in the throat or chest when food is swallowed
  • Jaundice (yellow discolouration of the skin or white of the eyes).

The Bottom line

Understanding what gut health is and how to look after your gut is imperative for overall whole-body health. The human digestive system is far more complex than previously understood, with a far greater overall impact than just the processing of food and providing us with the nutrients we need. Our guts are linked to many other parts of our bodies and if not taken care of, can have vast health implications.

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