Gut health. It’s the latest buzz word when it comes to health and nutrition. Not only are new ‘gut friendly’ foods popping up on supermarket shelves and in the trendy cafes but research on the links between the gut and health is constantly evolving making the gut more fascinating than ever before.
The gut – not its official name but certainly the name it’s referred to the most. The gut (our gastrointestinal tract) is a long tube that begins at the mouth and ends at the anus. The entire gut, which is roughly nine meters long consists of the mouth, oesophagus, stomach, small intestine (the duodenum, jejunum and ileum) and the large intestine (cecum, rectum, and anus) with digestive organs attached along the way. One of the primary roles of the gut is to digest and absorb food. Digestion begins in the mouth when we chew food and saliva starts to break it down. Food then passes through to the stomach where gastric secretions of enzymes and chemicals digest it further. Once food moves into the small intestine the majority of nutrient absorption takes place. Food that can’t be digested, waste substances and some bacteria move into the large intestine, water is absorbed and the remaining contents are passed out as faeces.
Key message: The gut is the gastrointestinal tract which runs from the mouth to the anus to digest and absorb the food we eat.
The gut contains trillions of different types of bacteria, fungi and viruses (around 2kg in adults) which collectively make up the gut microbiota (also known as gut microbiome or gut flora). Everyone has a unique makeup of gut microbiota which is influenced by genetics, environmental and lifestyle factors, disease, medications and diet. Our gut microbiota helps to digest foods, produce some vitamins and amino acids and plays an important role in the immune system. Gut microbiota has well established links with irritable bowel syndrome and gut disorders but recently scientists have begun to discover links with gut microbe and metabolism, obesity, type 2 diabetes, heart disease, mental health and brain health.
Key message: The gut contains trillions of bacteria, fungi and viruses collectively known as the gut microbiota. The latest research is uncovering links between the gut microbiota and chronic diseases such as type 2 diabetes, cardiovascular disease, obesity as well as immune function, mental health and brain health.
Pre and Pro biotics
Probiotics are live bacteria and yeast that are beneficial for our gut microbiota as they help to maintain the balance of good bacteria in our gut. Probiotics are found naturally in fermented foods such as yoghurt, kimchi, sauerkraut, kefir, kombucha, tempeh, miso soup and fermented vegetables. The amount of probiotics in commercial products varies greatly, some products may state that they contain ‘live and active cultures’.
Prebiotics are non digestible components of some foods that promote the growth of healthy microbes in our gut. Prebiotics are mainly non digestible carbohydrates like fibre, resistant starch and other non digestible carbohydrates like inulin. Foods rich in prebiotics include fruits (apples, bananas), vegetables (garlic, onions, leeks, chicory root, Jerusalem artichokes, asparagus) wholegrains (oats, barley, rye, wheat bran) as well as beans, lentils and legumes.
Think of your gut like a garden. The probiotics are seeds that you plant into your ‘gut garden’ and the prebiotics are the fertiliser that allow the seeds (or probitoics) to grow & flourish.
Key message: Probiotic foods contain live bacteria and yeast similar to those found in our gut. Eating probiotic foods helps to balance out the amount of good bacteria in our gut. Prebiotic foods promote the growth of the healthy bacteria in the gut. Both pre and probiotic foods are essential for good gut microbiota.
Diversity is key
Most people have about 20 main foods they eat each week which isn’t ideal when it comes to gut health. To make our gut microbes flourish we need to have a variety of different pre and probiotic foods. Even if you eat healthy, wholesome & fibre filled foods it’s important to mix it up – try different fruits and vegetables, different grains, a variety of pules and beans and different kinds of fermented foods too. When it comes to gut health diversity is key.
Key message: A diverse gut microbiota is considered to be a healthy one. Eat a wide variety of pre and probiotic foods to allow a wide range of healthy gut bacteria to grow and flourish.
Unsurprisingly a diet high in highly processed foods and junk foods isn’t ideal for gut health. Consuming a diet high in junk foods can drastically reduce the variety of bacterial species in the gut within a few days. High fat, high sugar and high meat diets have also been linked to poor gut health and gut microbiota.
Take it easy with the alcohol if you want to your microbiota to thrive. Excessive alcohol intake can also disrupt microbial balance in the gut.
It’s also wise to avoid restrictive diets and diets that eliminate entire food groups. A healthy, well balanced diet full of a wide variety of wholefoods is key for gut health.
One of my favourite styles of eating is the Mediterranean diet. It’s full of a variety of delicious, wholefoods such as fruits, vegetables, yoghurt, olive oil, fish, wholegrains, pules, legumes, nuts and seeds which makes it a brilliant gut friendly diet.
Key message: Limit highly processed foods and junk foods and avoid having a diet high in fat, sugar, meat and alcohol if you want your gut microbiome to thrive.
Gut health top tips:
- Eat fermented foods such as yoghurt, kimchi, sauerkraut, kefir, kombucha, tempeh, miso soup and fermented vegetables.
- Eat a huge variety of minimally processed wholefoods. Expand your horizons from your 20 key foods that you usually eat and start including new foods to your diet.
- Eat a fibre rich diet. High fibre foods will give you plenty of prebiotics to allow your ‘gut garden’ to flourish.
- Minimise highly processed foods and don’t overconsume fat or sugar. Incorporate more plant based rather than animal based protein into the diet.
- Don’t over do the alcohol.