Your body is like a planet. It is inhabited by trillions of creatures adapted to the various environments provided by different parts of your anatomy.
Every surface of the body exposed to the outside world – including skin, nose, ears, mouth, teeth, lungs, vagina and gut – are potential real estate for microorganisms. Some prefer the intense acidity of your stomach, others the salty moisture of your armpits. Body odour – both pleasant and unpleasant – is produced by bacteria. Most of our 100 trillion resident microbes are bacteria, but we also house viruses, fungi and archaea.
The most densely populated region of the body is the colon or large intestine. This is not surprising because the surface area of your gut is up to 100 times greater than the surface area of your skin. Right now in your colon an estimated 1000 bacterial species are breaking down food, manufacturing vitamins, buffering toxins and keeping harmful infections at bay.
The way we live our lives affects not only the earth and its animals but also the population of microorganisms that call us home. In return, the activity of our microorganisms influences us – our general health as well as our mood, energy levels, immune function, metabolic processes, food intolerances, even our height and weight.
The combined weight of the bacteria that inhabit your body is about 2kg – more than the weight of your brain (1.4kg)! A gram of faeces contains more bacteria than there are people on earth.
No two people have the same microorganisms living on their bodies, not even identical twins. In other words, everyone has a unique microbial identity, just as we have a unique fingerprint. This is one of the reasons why one diet does not fit all.
- When and how do we acquire our distinctive microbial population (known as our microbiota)?
- What role do they play in health and disease?
- Can gut bacteria really make a person thin or fat?
- What is the best way of cultivating a healthy microbiota and how important is this?
If you follow mainstream media and marketing, you’d be forgiven for thinking that you simply need to feed your ‘good’ bacteria with pre- and probiotics, avoid eating junk and add fermented foods to your daily fare. While this is good advice, the situation is far more complicated and nuanced.
For a start, different bacteria behave differently under different circumstances. ‘Bad’ bacteria are not always bad for us and ‘good’ bacteria are not always good. Just as humans behave differently in different situations, so do bacteria.
The other issue is that this is still an emerging area of science. We don’t have all the answers. We don’t even have all the questions. Every day new research hits my inbox. Scientists are in the process of determining what constitutes a healthy microbiome. (The microbiome refers to the genetic makeup of our microbiota but many people use the two terms interchangeably.) Scientists are starting to compile a list of bacteria that seem to be desirable – and the key appears to be diversity. The more different species you carry, the better. But just as restoring a rainforest involves more than adding or subtracting a few species, so too restoring optimal gut health will mean more than simply tweaking our diet to encourage the growth of more friendly bacteria.
Over the ensuing months I’ll answer the questions posed above and keep you updated on the latest research involving our merry microbes.
* To read other HEB’s in the gut series click below:
Very very interested in this subject and I trust and appreciate your blogs thankyou
And I appreciate your response – if I know a subject is of interest to people I’ll keep you posted on new developments.
Thank you for sending me your newsletters. I learn a lot from them.
Could you please which HEB products and which site on line I could purchase for myself.
I have a problem I’m 69 years old and if I have one drink of wine or beer next day I have to run
next day to the toilet.
Thank you for your help.
Hi Andrew, If you’re a fan of Shakespeare, you might recall the porter in Macbeth saying that alcohol promotes ‘nose-painting, sleep and urine’. For most people, every gram of alcohol they consume increases their urinary output by 10mL above what they would normally excrete. In other words, a standard glass of wine (100mL) containing 10grams of alcohol would result in 200mL of urine.
The reason for this is that alcohol travels to the pituitary gland in your brain and reduces its output of a hormone called vasopressin or ADH (anti-diuretic-hormone). This hormone stops you urinating. Therefore alcohol is like taking your foot of the breaks and you excrete more than usual. Another explanation is that one of the metabolites of alcohol is small enough to be filtered out by the kidneys and it drags fluid along with it.
If your response is in excess of this, you may have an issue with your kidneys or your pituitary gland. I would recommend you see your GP and ask for a full examination and perhaps a referral to a nephrologist (kidney specialist) or urologist. Your GP will be able to determine the best course of action for you. All the best!
I attended one of your weekends in Southern Highlands last year. I have struggled with Crohns Disease and lately had a really bad flare up. For the past 5 years I have been eating sensibly but have continued to gain weight; even after keeping a diary of my food intake the GP struggled to figure out why I was gaining weight
Finally with this flare up my GP suggested that I try the SCD diet to re-establish my gut flora. I am amazed the weight is just falling off, I feel good and experience minimal gut pain.
This article has come at the right time and I finally understand just how s gut flora really runs your body.
I look forward to future articles.
I’m so pleased to hear that your gut is much improved and your body is burning through its fat stores. Our gut flora has contributed a great deal to our understanding of why one diet does not suit all. In your case, your body does not tolerate many carbohydrates and hence an eating plan like SCD (Specfic Carbohydrate Diet) can be very effective. It’s also possible that gluten was contributing to your symptoms and since the SCD eliminates gluten, this has probably also been beneficial. The SCD has actually been around since 1924 when it was first devised to treat coeliac disease. Since then many patients with Crohn’s report that it helps them manage flare ups. Finally, all diets that reduce carbohydrates reduce insulin production. Insulin is the primary hormone that drives fat storage. The less insulin we produce, the more we use our fat stores for fuel. Keep up the great work!
Hello Dr Helena,
I have recently (3 months) had a colonoscopy which obviously clears everything out in the gut. In the last month my excrement has turned to a clay like substance,my mental health has deteriorated and my hair has fallen out ( not in clumps). My question is how do I fast track (from the science that you already know) getting my gut to a healthy state as the pain has been unbearable? I would really appreciate your opinion and any books that you believe would help.
Warmest regards Shauna
I’m sorry to hear that your health has declined so precipitously. There are a lot of things to consider in your situation. What was the reason for the colonoscopy in the first place? What did your gastroenterologist find? Have you seen him or her since the procedure and received any advice with respect to your post-surgical symptoms? The first step – if you haven’t already done so – is to return to your GP and gastroenterologist for them to shed light on what might be going on.
I don’t know where you live, but I also suggest that you contact the Centre for Digestive Diseases in Five Dock, Sydney: http://www.centrefordigestivediseases.com or ring 02 9713 4011 and speak to them about what you are experiencing. If you live in Sydney, would your GP be able to write a referral for you to see them?
In the meantime, basic principles of good gut health include avoiding processed food – especially products containing refined sugar, vegetable and seed oils (except olive oil) emulsifiers, preservatives and artificial sweeteners. The good things to include in your diet I’m sure you’re aware of: whole foods (especially vegetables) and fermented foods like yoghurt, sauerkraut, kimchi, tempeh, miso and kombucha. Having said that, different vegetables are tolerated differently by different people so you will need to eat mindfully and listen to your gut in order to observe what does and doesn’t agree with you. In some people (but not everyone) avoiding gluten may also be helpful.
A few preliminary studies have found that certain probiotics containing high concentrations of live lactobacilli may help people with depression and anxiety. Again it requires a very individual approach and no single probiotic cocktail has been found to help everyone.
There are also many factors other than diet that affect our gut microbes and the metabolites they produce. Regular aerobic exercise (30 minutes a day) is a stand-alone way of increasing gut microbial diversity (which is a cornerstone of good health) as well as increasing the numbers of butyrate-producing bacteria (another desirable).
Another well-studied method of improving gut health is to fast for 13 hours every night. In other words, leave a gap of 13 hours between dinner and breakfast every night. Also avoid snacking throughout the day. Eat no more than 3 meals and make them satisfying enough so that you don’t need to snack between meals. Our gut was not designed to have a constant influx of food.
Psychological interventions like CBT, meditation and mindfulness can also change what’s going on in our gut because of the constant two way communication between our brain and gut. Our health is part of our lifelong journey of personal growth. I hope my suggestions have given you a starting point.
This is such useful information. I have been following this fascinating area for some while as a lay person. So I’ll be very interested in what you reveal as always
What I like about this subject is that it illustrates how much our lives depend on the wellbeing of other lifeforms. Reigning in the indiscriminate use of antibiotics needs to become a major focus of medical practice.
Are you a “functional medical practitioner?
Do you share similar views as Dr Mark Hyman?
My sibling, Has told me to seek advice from such a professional.
I am not a Functional Medicine practitioner but I agree with the overarching philosophy that treating ill health needs to take into account a person’s whole life – their diet, daily habits, environment, stress levels and relationships. The focus in Functional Medicine is to determine the root cause of an illness and to individualise treatment for each person. This means that different people may receive different treatments, even if they present with the same symptoms. Within this context, I share some – but not all – of Dr Mark Hyman’s views in relation to diagnostic methods, dietary advice and treatments. The important thing is that you find a health professional with whom you feel comfortable, who listens to your concerns and who works with you in finding the most suitable approach for you. If your interaction with your healthcare provider leaves you feeling empowered to take positive steps to improve your health, then this is a good start. Before you even see a doctor, do your best to get regular good quality sleep, 30 minutes of exercise a day (a walk is fine or if you have physical limitations, whatever you are capable of) and a friend or family member to support you on your healing journey. Let your healing be an adventure!
Learning from your book, radio presentations & this blog is great but needing more to find the right solution or progress towards a solution for my gut health
Gut health is a burgeoning field with new research being published every day. We know from the Human Microbiome Project (HMP) that everyone’s gut bacterial composition is unique. In fact, the microbial differences between us are greater than our genetic differences. What this means is that YOU are the best source of your own answers. I imagine you’re already paying close attention to how your gut responds to different foods. In addition, gut health is influenced by sleep, exercise, stress, time spent in nature and a myriad of other lifestyle factors that we’re still piecing together. Observing and keeping a record of your symptoms in different situations may help you see what ameliorates or exacerbates your condition and you can then adjust your food and lifestyle choices accordingly. This may seem tedious but that’s the way of most scientific research. Small meticulous observations over long periods of time will eventually lead to solutions. Depending on where you live, you might also like to visit The Centre for Digestive Diseases in Five Dock, Sydney: centrefordigestivediseases.com. They are doing ground-breaking work in treating diseases of the gut. I wish you all the best on your journey.