You are what you eat. And when it comes to your gut health, what you eat has a big impact on keeping you and your gut in good shape. When your gut isn’t healthy, it can affect your mental health, mood, body weight, and a number of digestive disorders.

Feeding your gut microbes

Before you have your next meal, you may want to ask yourself: am I feeding my gut bacteria? A growing field of research is finding that our gut bacteria play a crucial role in our health. Feed these microbes well and your digestive system will work at its peak capability. And with 100 trillion bacterial cells in our gut, that’s a lot of mouths to feed.

The bacteria in our gut play an important part in our health and it is prebiotics that is the food that they thrive on. Think of prebiotics as a ‘gut fertiliser’ to promote the growth of beneficial bacteria such as Bifidobacteria and Lactobacillus.

Other benefits of prebiotics include improvement in gut barrier function, immunity and even regularity of bowel movements. Prebiotics can also help reduce the amount of potentially damaging bacteria in the gut by altering the pH, making it less of a hospitable place for the more harmful bacteria.

What to eat for a healthy gut

To keep your gut ecosystem happy, you want to be eating more foods that are high in different types of fibre including soluble and insoluble fibre and resistant starch. To do this, the simplest advice is to eat a wide variety of nutritious whole foods from all food groups, which would naturally contain different types of fibre. That means more vegetables, more fibre-rich foods and including some probiotic foods while easing up on highly processed junk food, added sugar and alcohol.

Some of the key prebiotic foods include:

• Aromatic vegetables such as onions, garlic, leeks, celery and Jerusalem artichokes. These are high in a type of carbohydrate called inulin which bacteria use to promote healthy colon cells and other health benefits
• Barley and oats are a rich source of the soluble fibre, beta-glucan. Beta-glucan acts as food for your good gut bacteria and helps lower cholesterol levels.
• Starchy foods such as cooked potatoes, beans and lentils and green bananas are a great fuel source for gut bacteria.
• Fermented foods such as sauerkraut, kimchi, kefir and yoghurt contain a good supply of healthy bacteria to add to your microbiome.

Smart food swaps

Eating more prebiotic foods will have you on the way to a healthy gut. And the good news is that a shift to a healthier diet can change the bacterial mix in a few short days. To illustrate, one recent study involving African Americans who swapped their meat-heavy, highly processed diet for a diet typical of African foods rich in beans and vegetables saw a positive change in gut microbes within just two weeks. And the reverse swap saw that when rural Africans switched to a typical American diet, their microbe profile was more in line with a higher risk of colon cancer.

These rapid changes in gut health with a switch to eating healthier will stay in place so long as you stick to the better food choices. So treat this like a long-term game where you make small changes and healthy food swaps over many weeks to months to make the changes sustainable. Something as simple as eating two pieces of fruit each day and choosing wholegrain foods over more refined grains is a great way to start. Then look at adding in more of the variety of prebiotic foods available to us.