Essential nutrients for good gut health other than fibre
Gut health refers to the function and balance of bacteria that live in harmony in your body. Gut health specifically focuses on the bacteria that colonise the colon of your gastrointestinal tract (gut).
Poor gut health has been linked to a variety of health concerns, including digestive problems such as irritable bowel syndrome, autoimmune conditions such as arthritis, metabolic diseases such as type 2 diabetes, and, more recently, Alzheimer’s disease. It’s critical that we maintain a healthy balance of the trillions of microbes (gut microbiome) living inside our digestive system to maintain our overall health.
How to support and maintain a healthy gut microbiome through food
Good gut health begins with what you eat. Eating a varied and high-fibre diet that aims to reduce salt, sugar and alcohol intake is essential to ensure you get all the nutrients you need, but also to support a healthy gut microbiome. Fibre is incredibly important, but there’s another nutrient that’s essential for gut health: zinc.
Why is zinc important for gut health?
Zinc is one of the key nutrients found in a wide variety of foods. Good sources of zinc include lean meat (beef, pork and poultry), fish and shellfish (oysters contain more zinc per serving than any other food).
Lesser amounts of zinc can be found in milk and dairy products, whole grain products, beans, seeds and nuts.
Zinc is essential for many of our body’s functions including wound healing, immune function and blood clotting. It’s also key in maintaining a strong intestinal barrier function, or lining of the gut, and helps to restore the gut wall lining if it becomes irritated. Zinc is also critical in the immune function of our body – particularly the functioning of immune cells that help our body reduce infection. Zinc is also an important antioxidant, which helps to prevent damage to cells, reduces inflammation and subsequently improves overall health.
Are you getting enough zinc?
Eating a diet rich in zinc-containing food is recommended for supporting and maintaining good gut health, particularly for those who suffer from increased intestinal permeability (also known as an irritated gut).
Australian standards recommend 11g of zinc per day for men and 8g per day for women.
Top five foods for zinc (per 100g):
1. Cooked oysters (fresh or tinned) - 17g zinc
2. Pumpkin seeds – 9.5g zinc
3. Lean roast beef – 6g zinc
4. Sunflower seeds – 5g zinc
5. Pork fillet – 3g zinc
To boost your zinc intake, you could try a zinc-boosting salad bowl: 1 cup mixed green salad (1g zinc) with 1 cup roasted pumpkin with 1tsp Moroccan spice (1g zinc)+ 100g canned, drained legumes (3g zinc) + 30g pumpkin and sunflower seeds(3g zinc) with 30g crumbled Greek feta (1g zinc) served with 1 slice of wholegrain bread (2g zinc) – for a total of 11g of zinc.
Other beneficial nutrients
Polyphenols are another important nutrient for gut health. They’re micronutrients found in certain plant-based foods, especially the skin of fruits and vegetables, as well as some spices. Polyphenols are enriched with antioxidants, which fight inflammation, protect our body’s cells against damage and reduce our risk of type 2 diabetes, some cancers and heart disease. It has been suggested that polyphenols can help boost our memory, but more research is needed.
Polyphenols can also aid in digestion through promotion of the beneficial gut bacteria, bifidobacterial and reduce inflammation as well as improve overall gut health, especially when consumed each day. Besides plant-based foods, good sources of polyphenols include beans, nuts and whole grains.
The fatty acids that are considered essential for our health can’t be produced by our body, which is why it’s important to eat foods rich in fatty acids. Omega-3 fatty acids, found in deep-sea fish, nuts and seeds have numerous proven benefits, including reducing inflammation in the gut and boosting the immune system. It also helps to maintain a healthy gut by supporting a balanced gut microbiome and encouraging growth of good bacteria. The best natural source of omega-3 fatty acids is fish, but you can also look to vegetable oil, such as canola, dark leafy greens, walnuts, flax seeds and chia seeds.
By making slight improvements to your diet, eating a wide range of food enriched in zinc or polyphenol, prebiotics and probiotics, and dietary fibre can help support a healthy gut microbiome and improve your overall health and wellbeing.
This article was written by Dr Cuong Tran
Dr Cuong D Tran is a senior research scientist and at team leader at CSIRO Health and Biosecurity Business Unit in the Food and Nutrition Program, and an affiliate senior lecturer at the University of Adelaide. He has a PhD in nutritional physiology and gastroenterology, and more than 15 years research experience in gut health and nutrition, and gut disorders and well-being in paediatrics and adults. Dr Tran has a research interest in gut barrier function and microbiome, particularly developing effective measures of gut health and function and how that impacts overall health and well-being. He has published over 50 peer-reviewed research papers ranging in topics including gut microbiome and health, zinc nutrition as a potential therapy for inflamed conditions of the gut, non-invasive testing for gut health and small bowel integrity and function.