Gut microbiota have been a hot topic in recent years as it was discovered that the structure and function of gut microbiota are of huge importance for our health and the occurrence of various diseases. A (negative) change in the structure or function of gut microbiota is called dysbiosis and has been linked to several ailments like mental illness, autoimmune diseases and metabolic diseases.
What are gut microbiota? The digestive tract consists of a large number of different microorganisms, including bacteria and fungi, and is one of the body’s biggest organs. Gut microbiota is the name used to describe the microorganisms that are found in the digestive tract.
What is the function of gut microbiota? Gut microbiota have several different tasks, including being responsible for breaking down and absorbing nutrients from food, which means they play an important role in our immune system, produce vitamins and convert hormones. And more!
How can I support my gut microbiota?
Fibre, fibre, fibre!
Considering how much of an impact our gut microbiota can have on our health and well-being, it’s useful to try to support them to promote the growth of healthy bacteria. One thing that has the most positive effect on our gut microbiota is our intake of dietary fibre. Dietary fibre, or fibre for short, refers to those carbohydrates that pass through to the large intestine without first being broken down in the small intestine. In the large intestine, the fibre is broken down by microorganisms in the gut microbiota to become short-chain fatty acids and gases. Certain fibres are fermented and become food for the gut microbiota’s bacteria and thereby promote the gut microbiota’s structure and growth. Which bacteria are promoted depends on what type of fibre we eat – both the amount and the type of fibre may have an impact on the balance between the different gut bacteria. Having a large number of different species of bacteria in the gut microbiota is a sign of a healthy digestive tract, so eating a varied diet allows you to contribute to a wider variation of bacteria in your digestive tract.
Examples of foods that are rich in fibre:
- Vegetables (such as broccoli, cauliflower, kale, red cabbage, onions, mushrooms, peppers)
- Pulses (chickpeas, beans, lentils)
- Wholegrain products (such as wholemeal bread, brown rice, oats)
- Root vegetables and potatoes
- Fruit and berries
- Nuts and seeds
How much fibre should we eat? Adults are recommended to get at least 25–30 grams of dietary fibre per day. If at the moment you are not used to eating a lot of fibre, it is a good idea to increase your intake gradually as it may upset your stomach to go too quickly from a low-fibre diet to one that is rich in fibre. The stomach needs time to get used to things, and to begin with the increased fibre intake may produce gases so that you feel bloated, but this will pass as the body becomes accustomed to it. If you experience discomfort after increasing your fibre intake, you can try reducing your fibre intake again somewhat and then increasing it slowly but surely. Another important thing to remember when you increase your fibre intake is that you also need to increase your intake of liquids. As fibre absorbs a lot of liquid in the digestive tract, you have to drink more liquids to avoid constipation.
Fats are important! Both the amount and the type of fats in the diet have been shown to be capable of having both beneficial and detrimental health effects on the gut microbiota’s bacterial structure. A high fat intake generally seems to have a negative impact on the structure of gut microbiota. As for the type of fats, good quality fats with a high proportion of unsaturated fats and a low proportion of saturated fats provide greater variation of healthy bacteria in gut microbiota whereas a high proportion of saturated fats may lead to the growth of unfavourable bacteria.
Examples of foods with a high proportion of unsaturated fats:
- Avocado
- Oily fish
- Nuts
- Seeds
- Rapeseed oil
- Olives
There are other things that may impact on gut microbiota both positively and negatively. Considerable research is being done on the subject to establish what these are and to acquire a greater understanding of our gut microbiota. So, I am certain that we are going to hear even more about this in the future and become even more knowledgeable about how our gut microbiota have an impact on us and how we can have an impact on them.