What is good bacteria?

Despite what we have been led to believe, not all bacteria are bad.

Each of us has around 100,000 billion viable microbes or bacteria living in our intestines. These microbes weigh around 1.5 kg in total and are referred to collectively as the microbiome.

Acidophilus bacteria - ProVen Probiotics


The bacteria are made up of over 1,000 different species and more than 5,000 strains, some of which are considered helpful and others that have been shown to be detrimental to health. The two most common species of helpful bacteria found in our gut microbiome are Lactobacillus and Bifidobacteria. Clostridium difficile is an example of a strain of bacteria that negatively impacts health, often termed pathogenic.

Maintaining balance between the helpful (good) bacteria and the more unhelpful (bad) species has been shown to be key to supporting a healthy digestive system. With the gut now understood to be central to health and containing more than 70% of our immune system, there is greater focus on natural methods for keeping our gut healthy.

95% of the microbiome is in the large intestine, with only around 50g (weight) of the microbiome residing in the small intestine.

With us from birth

The composition of our gut bacteria is initiated when we are born and develops through the first few years of our life. It is based upon the bacteria we are exposed to at birth and our diet and experiences from birth to around three years of age, after which it becomes set for the rest of our lives.

Affected by life

During our lives, the balance of this gut good bacteria is challenged by many things – what we eat and drink, the medications we take (particularly antibiotics), the environment we live in, the toxins we encounter and the amount of stress we experience.

If we live a high-stress life in a city, eat a diet high in sugar and processed foods, with lots of alcohol and we take antibiotics regularly, this can reduce the levels of good bacteria in our gastrointestinal tract and create ‘dysbiosis’ (imbalance), where the bad bacteria have taken over.

To help avoid this imbalance, it is useful to always keep our levels of good bacteria ‘topped up’ and there are two ways that we can help to support these good guys and ‘crowd out’ the unfriendly types.

Firstly, eating fermented foods such as sauerkraut, kimchi and kefir can help to ensure that our friendly (good) bacteria remain topped up. These foods were traditionally eaten by our ancestors before refrigeration was invented and are a valuable addition to a modern diet.

Alternatively, for those who choose not to eat fermented foods or who are looking for a quick and easy substitute for our native good bacteria, friendly bacteria supplements, often referred to as probiotics, maybe a useful option.

Gut balance is key

Our Microbiota

Our natural microbiota contains both helpful (friendly) and hostile bacteria. The main two species of helpful bacteria are Lactobacillus and Bifidobacteria.


Gut Balance

Many factors can affect the balance of the gut bacteria, including diet, sickness, antibiotics and other medications, stress, lack of sleep and even aging.


Imbalance Symptoms

An imbalanced bacterial population is known as ‘dysbiosis’ and symptoms include bloating, gas, indigestion and food intolerances, as well as low energy and reduced immunity.


Before refrigeration, humans used to eat lots of useful bacteria via fermented and cultured foods. As this is no longer the case, supplementation may help to support the bacterial balance.

The gut microbiome

Each of us has around 100,000 billion live bacteria living in our intestines.

Probiotics & Antibiotics

Research has shown that taking friendly bacteria (probiotics) alongside antibiotics can help to maintain a healthy balance of the bacteria in the gut.

Should I take probiotics with food?

If live bacteria supplements are not taken alongside food, 90-95% of the bacteria will die in the stomach acid.

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