We are not a completely solitary being as we are accompanied by microscopic bugs. Believe it or not, there are more microbial cells (40 trillion) than human cells (30 trillion) in our body1. Our body is made of water, minerals, protein, fat, bones and also trillions of bacteria, fungus and virus. We have these microscopic “pets” in our gut system known as the gut microbiota that helps us with our emotional wellbeing and many other health benefits. The growing research in discovering the vital function of the gut microbes is changing the paradigm of microbes from being disease-causing to health-promoting (excluding the pathogenic microbes). Most of the research findings have been mainly on bacteria, than fungus or virus. Though they are invisible with the naked eye, they are not to be underestimated. In fact, to be happier and healthier we need to please our symbiotic housemates. Happy gut, happy life.
A symbiotic relationship
A healthy gut microbiome provides a host of health benefits for the human body. When a person has a healthy gut microbiome, they are known to have a symbiosis experience as both the human (as host) and the microbes (recipient) benefit from each other2. A person who has a healthy gut microbiome will have more energy, less allergies, better immune system, digestion, weight management, mental clarity and emotional wellbeing. A healthy gut microbiome is meant to have diversity in the population3, a balanced ratio of the Firmicutes species of bacteria and the Bacteriodetes species of bacteria4, stability and resilience5 to cope with insults, and lastly, perform a myriad of functions6 to regulate, digest, detoxify and release good stuff. The gut microbiota break down food that the body can’t digest. They absolutely love prebiotic fibres. As they digest the prebiotic fibres the microbes produce important neurotransmitters, vitamins and nutrients, and short chain fatty acids, such as butyrate, acetate and propionate7. These by-products provide protection to the gut lining, regulate the immune system, maintain glucose stability, reduce inflammation, regulate appetite8, protect the nerve cells from damage9 and maintain health to the gut lining10. Interestingly, the gut has been coined as the second brain due to the existence of the vagus nerve that connects the gut and the brain and they send signals to each other. The neurotransmitters that are produced in both the gut and the brain contribute to feelings and emotions. What these gut microbes can do is like a miracle pill. But when a human host does not provide the right food for the microbes to thrive and grow, there is a dysbiosis, which has been linked to various diseases such as Type 2 Diabetes, obesity, colon cancer, autoimmune condition, inflammatory bowel disease, psoriasis, coeliac disease, arthritis, anxiety, depression and more2.
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We all have our own unique microbial profile that begins from the womb and becomes modified depending on our diet and lifestyle. A baby is first exposed to the microorganism from the mother during a vaginal delivery and at breastfeeding. The first 1000 days of life are critical for the building of the microbial population in a baby’s gut. There are a number of factors that contribute to a baby’s gut microbiota11, such as: the mother’s health status and diet during pregnancy, vaginal or caesarean birth, breastfed or formula-fed, exposure to antibiotics, and more. Babies who are exposed to a healthy maternal diet and status, born through a vaginal birth, breastfed longer before eating solid food and not exposed to antibiotics, have a higher probability in establishing a stronger immune system, less allergies and healthier development11. A mother’s condition with high body mass index and underlying disease, along with habits of not exercising, eating non-nutritious food, smoking or alcohol consumption can alter the maternal gut microbiota, and may lead to pregnancy complications such as gestational diabetes and preeclampsia. All mothers desire the best for the health of their babies. While life complexities can interfere, it is never too late to make changes. The more you understand the importance of diet and lifestyle for the gut microbiota during pregnancy and after birth, the greater your freedom to choose wisely.
In adulthood every individual has the opportunity to still make lifestyle decisions to heal and enhance their gut health. Underlying infection, period of exposure to antibiotics and medications, genetic predisposition, sedentary lifestyle, poor nutrition of low fibre diet, high intake of saturated fat and sugary foods, and stress, to say the least, are some of the major factors that contribute to an imbalanced gut microbial population. Even a partial sleep deprivation in one night can modify the gut microbiota diversity and function12. While it is difficult to determine generally how long a person’s gut flora can be restored, there are choices that people can make to start to feel better.
10 steps to improving your gut
Here are 10 things that can help improve your gut microbiota balance, diversity, resilience and function:
1. Eat a whole-food plant-based, fibre-rich diet. While it seems daunting for some that we are recommended to eat at least 5 serves of vegetables and 1-2 serves of fruit daily, challenge yourself to daily introduce an extra serving of vegetables and plant-based protein (nuts, beans and legumes) to your diet.
2. Include prebiotic fibre foods such as garlic, onions, leek, shallots, spring onion, asparagus, beetroot, fennel bulb, green peas, snow peas, broccoli, sweet corn, savoy cabbage, artichokes, chicory root/inulin, lentils, soybeans/products, chickpeas, red kidney beans, whole grains, baked beans, flax seeds, jicama, raspberries, green bananas, apples
3. Aim for a rainbow on your plate. Challenge yourself to try a new or different to the usual vegetables and fruits per week.
4. Include a daily dose of fermented foods. Have a kimchi, or sauerkraut, tempeh, miso, kombucha, kefir, natural unsweetened yoghurt.
5. Be active and exercise daily. The recommendation is at least 150 hours per week of moderate exercise, which is 30 minutes per day for 5 days/week. If this is new to you, start with 10 minutes walking per day, either in the morning, or during lunch time.
6. Get enough sleep. The right sleep period is 7-9 hours for adult and 8-10 hours for teenagers. If you have difficulty in sleeping, wind down with chamomile tea, a relaxing bath, a book to read; and avoid checking a digital device 1 hour before bedtime.
7. Manage your stress. Practice 5 minutes abdominal deep breathing, outdoor walk and daily gratitude.
8. Give up smoking and drinking alcohol. If you need to drink something, grab a kombucha.
9. Avoid using antibacterial toothpaste and mouthwash. This can damage the beneficial bacteria, create antibacterial-resistant microbes which then changes the bacteria flora in your mouth. Use natural soap and cleaners and avoid aggressive cleaners such as bleach.
As Hippocrates said 2400 years ago, “All disease begins in the gut”. If we can help to look after our gut microbiota by providing it the right kind of food, we will be able to reduce the risk and development of various chronic disease, survive and thrive. Do yourself a favour: feed your gut the right things and it will love you back.
Christiana Leimena has worked in cardiovascular research in molecular cardiology and hypertension. She obtained her PhD through the University of New South Wales and did her postdoctoral training at Loma Linda University, California. She has a passion in educating and promoting whole-person health and nutrition. She loves the outdoors and cooking.
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