A basic guide to gut health, key terms defined and explained.
Understanding gut health; 1 the basics
The scientific investigation of gut bacteria and its relationship to wellbeing is at a very early stage. There are discoveries every week that support, coexist with or contradict earlier findings. It’s a rapidly developing and dynamic area of human knowledge. The good news is, there are many resources available to anyone who wants to understand and take control of their own health through diet.
As a starting point there are a few concepts that are best understood at the outset. Not everyone uses these terms in the same way but try these definitions as a starting point.
Microorganism is widely used in talking about gut health, it is a general description for any organism that is too small to see with the naked eye. Some scientists prefer not to use the word but you are likely to come across it widely if you start reading about gut bacteria. Bacteria, viruses, archaea and fungi are all typically included in the term.
Microbiota is generally used to denote the population of microbes in any given community or system. Flora appears to have largely the same meaning as microbiota and appears interchangeably. For example gut flora means the same thing as gut microbiota.
The aggregate of all the genes of an entire population of microorganisms in any environment is described as a microbiome.
Typically scientists divide human microbiota into populations linked to their environment, such as skin, mouth, nose, digestive tract, and in females also the vagina. The largest population of microbes occur in the digestive tract, also known as the gut. Bacteria are the largest type of microbe in the human gut and bacteria reflects the dominant interest of scientific research. Gut bacteria are the main recipients of the benefits of prebiotics and probiotics, that is why the term gut bacteria and gut health is so prominent in media accounts of research findings. Technically speaking the plural of bacteria is bacterium but you will rarely see this outside of science journals, bacteria is typically used as the singular and plural form in most everyday situations.
A key point to make is that the gut has an important two way communication system with the human brain. That means to think of fermented food and drinks as only involved in what happens in the intestinal tract is a mistake. What we eat and drink has has the potential to exert a widespread influence across a number of systems.
As science begins to unravel the importance of gut bacteria to health and wellbeing, there’s never been a better time to learn about human microbiota.
So what’s the big deal about the fermentation of food and drink? Why is there such an interest in it now when it’s been around for thousands of years? The growing ability of science to study microorganisms has opened up research linking the human microbiome to a range of health and wellbeing benefits. Even though this research is at an early stage, there are signs that our understanding of the human condition is entering a new era. Fermentation has a central role in this process, prebiotics and probiotics may be able to make a significant contribution to the quality of our lives and the state of our health.
The awareness that fermented foods may be beneficial is a useful starting point, but there are resources available for anyone wanting to know more. Maggie and I have signed up for the Coursera MOOC, Gut Check; Exploring Your Microbiome. MOOCs are multiple open online courses; essentially short samples of higher and further education. They are typically free and offered by experts in their fields. All materials are available online, and a study commitment of three to five hours for between four to eight weeks are required by students. There is usually an assessment required to complete a MOOC and a verified certificate may be available for a fee.
We will provide a weekly report of the Gut Check MOOC. But for anyone considering signing up for the course, it starts with a basic outline of the microbiome and microbiota (What is the human microbiome? What’s in your gut and how is the human microbiome studied?). It takes a little effort, but it is accessible to most people with a desire to learn and a basic knowledge of biology. This course is offered on the Coursera platform, there are other MOOC providers and free courses available in the same or similar areas of study. We welcome feedback about this or similar resources, feel free to enter your comments in the box below.
Home fermentation, have you tried the Kilner fermentation set?
Is a home fermentation kit necessary? For the occasional production of sauerkraut I’m not sure that special equipment is essential. Maggie has managed to keep us supplied with our fermented foods simply by using medium sized jam jars, and a range of normal kitchen utensils. The point she always stresses is that everything has to be clean. The fermentation vessel should be thought of as a bacterial incubator. If you incorporate harmful bacteria into the incubator it will inevitably grow quickly. You should throw any tainted product away , clean everything and start again. One of the many appealing aspects of home fermentation is the relatively low cost of fermenting produce. Consider that at current prices a liter of organic sauerkraut can be created for less than 50p (ten bob!).
I know that previous generation of home fermenters from Poland and Germany actually had a range of fermentation pots and tools that were accumulated through the course of married life (I don’t remember seeing any of these is the kitchen of my mother or grandmother). In particular ceramic pots that were dedicated fermentation vessels. They had necks wide enough that a small plate or large saucer could be accommodated within to keep the fermented product under the water level.
With the rising interest in home fermentation equipment has passed from specialist shops and online retailers into mainstream retail outlets. We purchased a Kilner fermentation kit at the weekend. Our primary motivation was to increase the volumes of our product. Not only has our own consumption increased but we are also sharing more with our own friends and family. It certainly seems that the public awareness of the benefits of fermentation is growing. The Kilner kit was fairly priced (£18) when compared to similar products and the fermenting jar was around the size we were looking for (3 liters). It all seems OK, we’ll report back when our first batch is ready (cabbage and carrot). We have no particular connection with Kilner, save that we use their 1liter fermentation jars already.
We’d be really interest in what other home fermenters use, and any equipment related tips would be most welcome. Feel free to leave any suggestions, comments or feedback in the box below.
People suffering from migraines tend to have particular profile of bacteria linked to nitrate processing.
I am keen not to overstate the potential of any individual scientific study. However this story highlights exciting news about a potential relationship between bacteria and migraines. In 2016 The Guardian featured a study that appeared to demonstrate a link between the efficient break down of nitrates in humans and the occurrence of migraines. As I understand the research, migraineurs (people that suffer from migraine) tend to have more nitrate reductase bacteria in both the mouth and in stool samples, than the wider population.
Nitrate reductase genes are responsible for processing nitrates in food and drinks, point being the greater their abundance the more efficient the nitrate processing. So getting more nitrates from food (compared to non migraineurs) may be linked to triggers for migraines. Obviously further research will be needed but the link between nitrates and headaches is not new. What this study is demonstrating is that the key might rest with the microorganisms in the mouth and gut.
Many migraine sufferers are aware of a relationship between certain foods and increased risks of attacks, through chocolate and wine for example. It is also known that certain drugs high in nitrates can provoke severe headaches. When broken down, nitrates lead to increased blood circulation in the cardio vascular system, this increase may be a key factor in migraines. The complexity of the human microbiome, particularly the gut-brain axis, makes demonstrating causality between food and health challenging. However this seems like a promising area of research. Controlling the intake of foods high in nitrates might be a short term solution. But given that fruit and vegetables are rich sources of nitrates, cutting down on them could present a range of risks and benefits. For more information visit the Migraine Action or Migraine Trust websites.
We always welcome your feedback, comments in the text box below. Thanks for Peter for suggesting the subject and as always please read our disclaimer.
The overuse of antibiotics is a major health concern. Probiotics may support the lower consumption of antibiotics by boosting overall health in humans and animals.
I am in the process of writing a basic guide to probiotics, but a general description is,
‘microorganisms contained in some food and supplements that have proven and assumed benefits to human and animal health’.
A key point at the outset is that it is hard to prove causality in such matters. Demonstrating correlation (people that have particular gut bacteria tend to have or not have a particular illness) is much simpler. The evidence linking probiotics and health is both causal and correlational. The point of probiotics is to change (improve) the profile of gut flora so that it has more positive and less negative microorganisms. This is a long road of which we are at the beginning.
Antibiotics are drugs designed to destroy or inhibit the growth of bacteria harmful to humans, animals or other organisms. I acknowledge the potential lifesaving benefits of antibiotics, they are an important part of modern healthcare. But the widespread overuse of antibiotics in industrialized societies is creating superbugs, bacteria that are resistant to all known antibiotics. This problem was the subject of the film Resistance which I recently saw on Netflix. The issue of superbugs is not new and the discoverer of penicillin, Alexander Fleming discussed resistance in the mid 1940s. If you subject bacteria to an effective antibiotics most will die off, but surviving bacteria can develop resistance to that antibiotic. If you repeat the process often enough you risk creating bacteria over time, that become resistant to every antibiotic they have been exposed to.
Sometimes humans are given antibiotics when they are not needed, and so we may carry around bacteria that have a resistance to some antibiotics, this is a problem in itself. A key point that the film Resistance makes is that contemporary farming methods can involve the routine administration of antibiotics to hundreds of millions of animals every year. Antibiotics appear to make some animals grow bigger, thus increasing their cash value. However intensively farmed animals can live in insanitary conditions, exposed to fecal matter for most of their lives. Forcing animals to live in an environment where high levels of dangerous bacteria are present, thus necessitating the use of antibiotics as a routine measure, can be described as a perfect breeding ground for superbugs.
The standards of animal welfare vary from country to country and the use of antibiotics in the EU generally is lower than some other parts of the world. But it’s still a major problem according to a recent report. Conceptually the idea of eating animals is increasingly unacceptable to many people. However the logic of forcing animals to live in terrible conditions their whole lives, only sustained by large amounts of antibiotics is obviously flawed. Not only are people eating animals that have endured life long suffering underpinned by the consumption of drugs. But this process may also be creating bacteria resistant to those drugs. The use of last-resort antibiotics for humans such as colostin, is increasing according to official data. When colostin is used it can indicate other antibiotics were ineffective against the harmful bacteria.
So what has this got to do with fermentation and probiotics? Firstly antibiotics generally kill and inhibited some good bacteria. Where health is at risk this is clearly an appropriate course of action. However as the importance of gut flora to health becomes better understood we should consider the need to maintain gut bacteria at healthy levels. Secondly the better our overall health the lower the risk of illness and presumably the less need there will be to take antibiotics. Just to be clear, probiotics are not a substitute for antibiotics, there are some very dangerous bacteria in our environment for which antibiotics may be the only cure. My position is to abandon the overuse of antibiotics in animals and humans so that when we (and animals) get really sick we will have antibiotic treatments that continue to work. The third point is eating animals that have lived a life in potentially dangerous bacteria, sustained by routine antibiotic consumption seems irrational. Wouldn’t it make more sense to maintain animals in healthy conditions, with feed rich in probiotics, reducing the need for antibiotics in all but essential cases?
Is temperature linked to the quality of your sauerkraut?
In the short time we have been running this blog we have been asked about the optimum temperature for the fermentation process to take place. We have successfully fermented a range of foodstuffs at room temperature, let’s say from 18oC to 22o. There is no method in this, it is simply that Maggie was brought up to leave the fermenting vegetables in the kitchen or a heated utility room. As such we’ve never been tempted to leave them in the garage or garden shed. As different types of cabbage take different amounts of time to ferment into sauerkraut, it always seemed likely that temperature is a variable in the process.
I eventually became impatient not knowing, I was also intrigued by the idea that the quality of our own sauerkraut fermentation could be qualitatively improved by allowing it to take place at a slightly lower or higher temperature. The first two science papers I found dealing with the issue didn’t offer explicit conclusions, however third time lucky! India is one of the world’s big producers of cabbage, the spoiling of the raw cabbage before it gets to the consumer is a significant problem. So Indian interest in fermentation is something that is culturally relevant but also has commercial implications. An article in the Indian Journal of Ecology from 2017, Effect of Temperature on Fermentation and Quality of Sauerkraut provided a lot of useful data.
In an experiment, Pran Krishna Thakur, Payel Panja and Jahangir Kabir tested the quality of sauerkraut produced at a low (15o-20o C), ambient (25o-30o C) and high (35o-40o C) temperatures. The paper is well written if you’d like to know more about yeast and bacterial profiles of sauerkraut fermentation at different temperatures follow the link. However the headline is that the sauerkraut was of a higher quality when fermented at the lower temperature (15o-20o C). This is in line with the general advice, however it’s worth noting that the experiment was undertaken with the shaan variety. I suspect that there may be some variability with different types of cabbage, but that’s a story for another day.
Show someone your love by taking an interest in their long-term health and wellbeing. Fermentation is a game changer.
The media (traditional and social) are full of valentine news, view and suggestions. Local traders, shops and supermarkets have an overwhelming array of products linked to St Valentine’s day. However the way in which you decide to treat your loved one says a lot about you. Whilst chocolates, Champagne or roses spring immediately to mind they may by simple clichés of what people are supposed to give, rather than lasting indications of love.
Perhaps a different approach would be to offer your partner (and yourself) something likely to offer nourishment and a lasting health benefit. It is easy to overstate the qualities of naturally fermented probiotics. But we can feel confident that they are likely to make a long lasting contribution to wellbeing in a number of ways. Evidence is starting to emerge that positive gut flora, may be correlated with, stable weight, and generally improved physical and mental health across a number of measures.
Clearly probiotics are not just for February the 14th, and moving towards a healthy diet is a long term project. But talking about fermented foods or trying them for the first time, may be a great way of showing your partner that you really care, and that you want them to enjoy the best possible health. When you create fermented foods at home, not only are your own family exposed to the product, but the idea and your positive actions can influence a wide circle of friends. Something that can’t be said of a bottle of fizz or a bunch of roses.
Whatever you do, and whoever you do it with have a great day.