Your gut is home to trillions of bacteria and other microorganisms that have an impact on your whole-body health. Many factors, including the foods that you eat, can impact the type of bacteria found in your digestive system and whether they grow, survive and flourish.
Why is it important to have a healthy digestive system?
A healthy digestive system is the cornerstone of overall health and wellbeing, since it brings nutrients to the body for energy, growth and cell repair. Without a strong digestive foundation, many body systems can suffer, including your immunity and mental wellbeing.
One of the fundamentals of healthy digestive function is your gut microbiome. This complex ecosystem that lives mostly within your large intestine, assists with digestion, stimulates the immune system, helps synthesise some vitamins and amino acids, produces important short-chain fatty acids and helps protect us from pathogenic organisms that might enter the body through our food or water.1
Each person’s gut microbiome is unique, much like our fingerprints. It is determined by many factors including our DNA, how we were delivered at birth, whether we were breastfed or not, our diet and other environmental exposures and health behaviours.1 When it comes to a healthy, resilient gut microbiome, diversity of gut bacteria is key.2
What can upset gut bacteria?
The dynamic and living nature of our gut microbiome means it can change and fluctuate depending on many things we encounter on a daily basis. Regular stress can reshape the composition of the gut through stress hormones and inflammation.3 Medication, such as antibiotics, can have a significant and negative effect on gut microbes.2 The foods we eat, and our dietary patterns can also have a profound influence on the abundance of different types of bacteria in the gut. For example, artificial sweeteners can disrupt the balance and diversity of the gut microbiome and people on restrictive diets (raw food, “clean eating”, gluten-free), show a lower abundance of several key bacteria species.2
On the other hand, eating certain types of foods can have a positive effect on your gut health. Prebiotic foods feed and fertilise the beneficial bacteria in the gut, and probiotic (fermented) foods contain gut-friendly bacteria and may encourage a more diverse gut microbiome.
What are the top foods for gut health?
Eating a wide range of foods and drinks can encourage a happier inner ecosystem. Some of the top foods for gut health include:
- Kefir – A fermented milk drink that contains several important strains of beneficial bacteria
- Yoghurt – Provides a source of gut-friendly bacteria. Look for a brand that says “live” or “active” cultures
- Sauerkraut – A traditional food in many countries made from finely shredded cabbage that has been fermented by lactic acid bacteria. Add it as a side on your dinner plate, in a sandwich or on top of your avocado toast
- Miso – Miso is full of bacteria that can contribute to improved gut health. Make a delicious soup with miso paste or add it to broth
- Tempeh – Made from fermented soybeans and rich in probiotics, protein and prebiotic fibre, tempeh can be used as a meat alternative in stir-fries or salads
- Kimchi – Similar to sauerkraut, kimchi is a traditional Korean dish made from fermented cabbage, radish or cucumber. Add it to rice or serve with scrambled eggs
- Kombucha – A fizzy drink brewed from tea, sugar, bacteria and yeast that supports gut health. You can make your own using a ‘scoby’ (symbiotic culture of bacteria and yeasts) or buy from a health shop, cafe or supermarket
- Garlic – Acts as a prebiotic by promoting the growth of beneficial bacteria in the gut
- Onions – Similar to garlic, onions contain prebiotic fibre and may help strengthen your gut health
- Leek – High in prebiotic inulin fibre, a good food source for gut microbes. Add leeks to soups, stews, bolognaise, quiches and omelettes
- Asparagus – Another prebiotic source to support digestive health
- Chicory root – Also high in inulin, the prebiotic fibre that feeds and promotes the growth of healthy bacteria in the gut. Delicious as part of chai tea
- Dandelion root – More than a common backyard weed, dandelion root is a good source of gut-loving prebiotic fibre to support microbial balance. Use with chicory in a chai (along with ginger, cinnamon, peppercorns, cardamom, honey and your choice of milk) or on its own as a coffee alternative
- Bananas – A source of prebiotics, especially when a little unripe
- Oats – Have prebiotic effects and may increase the abundance of gut bacteria. Eat as porridge or add to baked goods
Benefits of supplementation
You can also assist healthy gut microbe balance with a probiotic supplement. Probiotic supplements contain specific strains of beneficial bacteria at high strengths to support different health issues and symptoms and allow for a more targeted approach to gut health.
- Harvard Health, The Microbiome, The Nutrition Source, viewed 17 November 2022, https://www.hsph.harvard.edu/nutritionsource/microbiome/
- Valdes A 2018, ‘Role of gut microbiota in nutrition and health’, BMJ, vol 361
- Madison A 2019, ‘Stress, depression, diet, and the gut microbiota: human–bacteria interactions at the core of psychoneuroimmunology and nutrition’, Curr Opin Behav Sci, vol 28, pp 105-110