The gut microbiome consists of a unique, diverse mixture of trillions of microbes – bacteria, viruses and fungi and it is essential for digestion, immune function and overall health. In a healthy gut, although there is a combination of beneficial and pathogenic microbes, the beneficial microbes outnumber the pathogenic ones.
What are some of the benefits of a healthy gut microbiome?
- It increases good (HDL) cholesterol and decreases bad (LDL) cholesterol, by producing enzymes that metabolise the more harmful cholesterol (zoe, 2024)
- It assists weight regulation by regulating appetite, metabolism, and fat absorption and storage (Koutoukidis et al., 2022)
- It helps maintain bone density by increasing oestrogen bioavailability & increasing the promoting effect of vitamin D on bone mineral absorption.
- It modulates the immune system, improving immune response.
- It positively influences mental health through the gut brain axis.
What can lead to an unhealthy (dysbiotic) gut microbiome?
- Certain medications- alter the microbiome in favour of pro-inflammatory microbes.
- Antibiotics -these generally kill all the gut microbes and can lead to an overgrowth of the less beneficial ones.
- Reduced dietary fibre and plant diversity- leads to reduced microbial diversity (a cause of dysbiosis).
- Lack of dietary probiotics – leaving the gut vulnerable to disease causing microbes.
- Alcohol – can deplete microorganisms with anti-inflammatory effects allowing those microbes with pro-inflammatory effects to proliferate.
- Excessive stress – can suppress the beneficial bacteria and allow harmful bacteria to flourish.
- Lack of sleep – increased cortisol, inflammation and metabolic imbalances can lead to a decrease in beneficial bacteria and an increase in harmful pathogens.
What can I do to improve my gut microbiome?
- Increasing the quantity of fibre in your diet – at least 30g/day (ensure that you drink at least 2L of water a day and increase the fibre quantity in your diet gradually).
- Increasing the diversity of plant foods in your diet – aiming for 30 different plants/week- including as many different colours as possible.
- Eat a variety of probiotic foods (such as live yoghurt, kefir, kimchi, sauerkraut etc).
- Reduce sugary and processed foods.
- Reduce your alcohol intake.
- Reduce the saturated fat content of your diet.
Foods to focus on:
Eat a diverse colour of plant foods including vegetables, fruits, nuts, seeds, herbs and spices to help feed the beneficial microbes.
Eat a variety of probiotic foods daily – such as sauerkraut, kimchi, miso, live yoghurt and kefir to increase the microbial diversity.
Include extra virgin olive oil in your daily diet – it reduces the abundance of pathogenic bacteria and stimulates the growth of beneficial bacteria
Limit the amount of highly processed foods in your diet which often contain excess salt, emulsifiers and artificial sweeteners which can all damage the health of your microbiome.
Lifestyle factors to aid a healthy microbiome
An overnight fast of 12-14 hours gives the gut microbiome time to rest and repopulate.
Stress reduction – inflammation caused by stress can increase pathogenic bacteria.
A good nights sleep – Poor sleep patterns reduce the diversity of the gut microbiome.
Take regular exercise which can improve the health of the gut microbiome by enhancing gut motility, reducing inflammation and strengthening the gut barrier. However be careful not to over exercise as this can have the opposite effect.
To Sum up
A healthy gut microbiome is imperative for overall health. To maintain and improve the health of your gut microbiome aim to eat at least 30 different plant foods a week, eat at least 30g of fibre a day, and try and include some probiotic foods; keep alcohol highly processed and sugary foods to a minimum, get plenty of sleep and practice stress reduction techniques.
