You’ve probably heard of the word ‘microbiome’ being tossed around occasionally when there’s talk of health, weight loss and well-being, and for good reason. Over recent years, the topic of the human microbiome has been of great interest among healthcare researchers and nutritionists alike. And why has this now filtered through to the life sciences?
It seems that a lot of the ‘human condition’, from your physical health to your state of mind, appears to be linked to the microbes living inside of you. Just so you know, there are plenty. So, it’s no surprise that the human microbiome is one of the fastest moving points in medicine and science.
Each of us is many. Each of us is legion.
Inside and out, each of us harbours a huge array of micro-organisms. We host bacteria (the biggest among the microbes), single-celled organisms such as archaea and protozoa, fungi, and even viruses! Collectively, these organisms are called the ‘microbiota’. Your ‘microbiome’ is essentially the genes of all the microbiota combined.
To put things in perspective, the average human body has 50-100 trillion body cells (also known as ‘somatic’ cells). Bacteria, which constitutes the largest group within the human microbiota, has an estimated 75-200 trillion individual organisms. Combined, the microbiota weighs about 2-5 pounds (around 0.9-2.3 kg), 3 pounds being roughly the weight of your brain.
Genetically speaking, the number of genes in all the microbes in a person’s microbiome is 200 times the number of genes in the human genome. There are up to 1,000 species of bacteria in the human gut microbiome alone, and each of them plays a different role in your body. Most of them are extremely important for your health, while others may cause disease.
A person’s microbiome is so unique, even identical twins do not share the same microbiome. In fact, medical researchers are finding the human microbiome so unique, that Harvard Medical School is now working on a type of microbial fingerprinting. This would eventually allow for more bespoke/precise therapies for patients.
The symbiotic relationship.
It’s important to note that human beings (alongside other species on earth) evolved to live with microbes over hundreds of thousands of years. During this time, microbes have, in turn, adapted to play very important roles in the human body. In fact, without the microbiome, it would be very difficult for us humans to survive.
The gut microbiome begins to affect your body the moment you are born. You are first exposed to microbes when you pass through your mother’s birth canal. However, new evidence suggests that babies may come into contact with some microbes while still inside the womb.
As you grow, your gut microbiome begins to diversify, meaning it starts to contain many different types of microbial species. Higher microbiome diversity is considered good for your health.
Interestingly, the food you eat affects the diversity of your gut bacteria.
How does your gut microbiome influence your body?
There are many ways that your microbiome can influence your various body functions. Researchers are still scratching the surface, as each part of our body houses a diverse microbial community (or ‘flora’). For example, the microbial flora in our gut (stomach, intestines, etc.) is very different to that within our lungs, or on our skin.
To simplify things, here are just some of the ways that your microbiome can influence your body:
- Helps digest breast milk – Some bacterial species that begin to grow inside babies’ intestines are called Bifidobacteria. These microbes digest the healthy sugars in breast milk that are important for growth
- Helps digest fibre – As we grow, other bacterial species begin to emerge, some of which digest fibre, producing short-chain fatty acids. These fatty acids are important for gut health as they are the main source of energy for cells lining your colon
- Helps control your immune system – Your microbiome also controls how your immune system works. By communicating with immune cells, the gut microbiome can control how your body responds to infection
- Helping control brain health – There is new research suggesting that the gut microbiome may also affect the central nervous system, which ultimately controls brain function
Why is it important to take care of your gut microbiome?
The gut microbiome has recently been associated with various diseases and conditions. Medical researchers have found that diabetes, obesity, anxiety, and even autism, are influenced by the state or our gut microbiome. We are only beginning to uncover the many ways that microbes living within us can influence our health.
For instance, when your gut microbiome is imbalanced, it creates a state of dysbiosis. This can eventually cause various problems such as irritable bowel syndrome and inflammatory bowel disease. It can also affect your weight. A recent study of 1,500 people found that the gut microbiome played an important role in promoting ‘good’ HDL cholesterol and triglycerides. This helps to lower your risk of heart disease and stroke.
In case you didn’t know, our gut is connected to our brain via millions of nerves. The ‘happy’ chemicals (serotonin) are mostly produced in the gut by some of our friendly bacteria.
Ever heard of the term ‘a gut feeling’? The state of your microbiome not only influences your body’s health and well-being but also your state of mind and your emotions.
Simple & effective ways you can boost your gut microbiome.
There are many ways to improve your gut microbiome, which could effectively improve your health and well-being.
- Diversify your food intake – The more types of food you eat, the better. Diverse food intake leads to a diverse microbiome, which is a sign of good gut health. A good rule of thumb is to simply eat more fruits and vegetables
- Eat fermented foods – Popular sources for probiotics (good live bacteria and yeasts) you can eat are yogurt, kimchi, miso, tempeh and sauerkraut
- Eat prebiotic foods – Onions, bananas, apples, artichokes and asparagus are some examples of fibre sources that stimulate the growth of healthy bacteria. A good microbiome thrives on the prebiotic foods that you consume
- Reduce intake of processed food and artificial sweeteners – Artificial sweeteners stimulate the growth of unhealthy bacteria such as Enterobacteriaceae, which increases your blood sugar
- Take antibiotics only when necessary – Antibiotics kill many bacteria, both the bad pathogenic ones and the good bacteria in your gut microbiome. This ultimately causes dysbiosis, and a lack of microbial diversity
A healthy microbiome for a healthy you.
As a human being, your somatic (body) cells live alongside trillions of microbes, mostly bacteria. Different parts of your body house vast, diverse communities of microbes working in harmony to help with various body functions.
Your microbiome is uniquely yours. It doesn’t take much to take care of your microbiome. Just by eating more fruits and vegetables and some yogurt, your body is well on its way to having a good microbiome, and good health.
References:
- https://www.britannica.com/science/human-microbiome
- https://www.sciencedirect.com/topics/immunology-and-microbiology/microbiome
- https://www.theguardian.com/news/2018/mar/26/the-human-microbiome-why-our-microbes-could-be-key-to-our-health
- https://ep.bmj.com/content/102/5/257
- https://hms.harvard.edu/news/microbial-fingerprinting
