The ultimate guide to gut health

Gut health seems to be the latest lifestyle craze with more and more people sipping kombucha, taking probiotics and loading up on fermented foods.

But do you really need to look after your gut?

Here is a quick gut health guide to help you understand what all the fuss is about and explain how the health of your gut can have a big impact on the way you feel.

What is the gut?

The gut is your gastrointestinal tract starting at your mouth and including your stomach and intestines. It’s where your food is digested and absorbed by your body.

So then, what is gut flora?

To help do its job, the gut contains trillions of micro-organisms including more than 1000 species of bacteria, fungi and viruses. These bugs are known as the gut flora, or microbiota, and live together like an ecosystem.

We need a healthy microbiota and it needs us. The microbiota helps to keep us well by doing jobs our bodies can’t, such as breaking down fibre and producing vitamin K. While the microbiota relies on the food we eat to thrive.

How does your gut flora/microbiota keep you healthy?

Nurturing your gut can help you absorb more of the good stuff from your food, which helps to boost your immunity, regulate your digestion and even has a positive impact on your mood.

A healthy microbiota also draws more energy from the foods you eat and produces signalling molecules that may help to regulate your appetite, interact with your immune system and communicate with your brain. These clever bugs also help to break down toxic compounds.

What happens when you don’t have a healthy gut?

A gut microbiota with lots of different micro-organisms is a healthy gut, but because these bugs live together like a delicate ecosystem, it’s easy it upset the balance. Your diet, sickness and long-term use of antibiotics can all disrupt the balance.

When the bacteria in your gut microbiota are less diverse, bad bacteria can take over and feed on the lining of the gut wall. This can lead to inflammation in the gut and contribute to a whole range of health issues from allergies to lifestyle diseases such as obesity, diabetes, heart disease. It has even been associated with mental health problems such as depression and schizophrenia.

What about probiotics and do they help?

Probiotics are live bacteria, present in large enough numbers to have a health benefit. They are in foods such as yoghurt that contain live bacteria such as Lactobacillus acidophilus or Lactobacillus GG (LGG). Various probiotics may also be in supplements or added to unfermented foods. 

Probiotics from foods or supplments may reduce the number of harmful bacteria and provide new live bacteria for your gut, although this may only be transitory. Probiotics may be particularly important after a course of antibiotics to help restore the balance of your gut microbiota. 

In order to label a product “probiotic”, its health claim must be backed by scientific evidence, it must be in sufficient quantities to be an effective dose and it must be safe. There are specific strains for specific health conditions—for example LGG has been shown to support our immune system.  It’s important to get advice from your doctor or dietitian before taking a probiotic, as it may not be safe for some people, including pregnant women, infants and people with a compromised immune system. 

Fermented foods

Fermented foods are not the same as probiotic foods. Fermented foods are made through desired microbial growth and enzymatic conversion of some food components. They have been around for thousands of years and have contributed to our wellbeing, including enhanced digestibility and improved taste and texture. Yet fermented foods are not required to demonstrate any specific health benefits as probiotics do. 

Yoghurt is an example of a fermented food (made from milk) where the lactic acid-producing bacteria grow primarily on the milk sugar (lactose). As the bacteria multiply, they change the flavour, texture and nutrients of the milk. Some fermented foods may also contain probiotics if the bacteria are still alive and remain in sufficient number to provide a proven health benefit. 

Other sources of fermented foods with live bacteria include most cheeses, miso, natto, tempeh and most kombucha. If the fermented food is further processed (by pasteurization, heating, baking or filtering) they may no longer contain live bacteria.

What are three simple things you can do to improve your gut health?

1. The most important thing to do is feed the healthy bacteria by eating plenty of fibre rich foods, especially legumes, veggies and whole grains.
2.  Help replenish good bacteria by eating or drinking foods that contain probiotics/live cultures.
3.  Drink less alcohol and drink more water.

Want more information?

Our nutrition fact sheets, created by accredited dietitians, provide the latest nutrition and lifestyle information to help you understand which foods are the best to eat. Click here to see the gut health nutrition fact sheets.