What foods help gut bacteria?

Prebiotics are essentially what feeds the bacteria in our gut. They are substances in food that can’t be digested but will be fermented by bacteria in your gut and encourage those bacteria to grow. Most are types of dietary fibre and therefore are found in a wide range of plant foods, such as garlic, onions, bananas, wheat, rye, barley, soya beans and tomatoes. If you are getting a diverse range of foods in your diet, you will be getting all the prebiotics that you need.

Probiotics are the microbes – bacteria and yeasts. These are available as supplements or may be added to foods. There isn’t strong evidence that we should be taking these for heart and circulatory health. There is beginning to be evidence that they may be useful in some situations, but if you are generally healthy you don’t need to spend your money on supplements that may not deliver what they promise.

Fermented foods include yoghurt, miso, sauerkraut, kefir, kimchi and tempeh. There is limited clinical evidence to prove that they have a health benefit, but there are many potential mechanisms by which these foods may have a benefit. They’ve also been consumed by humans for thousands of years.

Although some of them can be expensive, depending on which ones you buy, you can often make your own more cheaply. Kefir, a fermented milk drink similar to yogurt, is fairly simple to make. If you want to try something new, fermented food can be a good place to start.

If you’re buying or making fermented pickles like sauerkraut and kimchi, bear in mind that they can be salty – check the nutrition labels and choose the one with the lowest salt per 100g. If you are choosing these products for their beneficial bacteria, you need to buy unpasteurised versions as pasteurisation will kill the beneficial bacteria. Look for the type that has to be stored in the fridge.

When it comes to yoghurt, look for a low-fat or fat-free yoghurt to reduce your intake of saturated fat and check that it includes ‘live’ bacteria. Greek-style yogurt in particular can be high in saturated fat.