Transforming health and wellbeing through fermentation
As a researcher working with the contemplative sciences, the key role that food has in health and wellbeing became evident to me. From there it was a small step to realize that fermentation and gut bacteria play an essential part in our lives. Do yourself and your loved ones a favour, check out the evidence linking gut bacteria and health now!
Fibre is an essential part of the human diet, strategic reviews indicate that consuming just 30g of fibre a day is correlated to reduced risk of colon cancer, type-2 diabetes, heart attacks and strokes.
For most of us there is a simple thing we can do to improve our short and long-term health, eat more fibre! The role of fibre in regulating digestion has been understood by humans for hundreds of years. But the full benefits linked to fibre (also known as roughage) are only just starting to be understood. A recent study published in The Lancet1 analysed a wide range of research and found that a shortage of fibre in our diets is linked to greater risks of type-2 diabetes, bowel cancer, heart attacks and strokes. In addition people that eat more fibre tend to have lower weight, lower blood pressure and reduced cholesterol levels. Amazingly the research suggested that consuming a mere 30g (1oz) of fibre a day was sufficient to deliver the full range of health benefits. To put this into some kind of perspective the 30g target can be reached by consuming four slices of brown bread, eating a handful of nuts and seeds in addition to the regulation five portions of fruit and veg a day. In essence it is available to most of us with only a few small changes to our eating habits.
Fibre consumed through our diet can be divided into two types, soluble and insoluble. Soluble fiber is generally though of as a prebiotic, which means it supports communities of helpful bacteria in the gut microbiome. Insoluble fibre does not dissolve in water and typically passes through the digestive system aiding bowel movements. Most fibre rich foods contain soluble and insoluble elements, today food science is more concerned with the total amount of fibre rather than the different forms (cellulose, pectins and beta glucans) we eat.
In summary; fibre is an essential part of the human diet, strategic reviews of the available evidence strongly suggest that consuming 30g of fibre a day is correlated to reduced risk of colon cancer, type-2 diabetes, heart attacks and strokes. There is a growing body of evidence that fibre also plays an important role in maintaining helpful bacteria in the gut microbiome.
Blueberries appear to offer a wide range of benefits including supporting guthealth.
Being a meditation scientist I often write about lifestyle choices that support augmented brain function and structure. As a general rule food that is associated with a healthy brain also positively correlates with improved general health and well-being. So having just blogged an article explaining how blueberry consumption can reduce effective brain age by up to 2.5 years I looked up potential relationships between blueberries and the gut microbiome.
Berries in general and blueberries in particular are good natural sources of polyphenols and therefore limit the effect of oxidisation, a cause of cell damage. But we also know that polyphenols lead to a healthier gut through the creation of metabolites which in turn support communities of beneficial bacteria.
As we age, chronic diseases become more likely1, when low grade inflammation is an underlying factor scientists refer to this as the “inflammaging” syndrome. In gut health inflammaging is linked to a weakening of a number of internal systems (homeostasis) including a reduction in the efficiency of the immune barrier. In experiments with mice it was suggested that polyphenols reduced intestinal inflammation and led to the modulation of the gut microbiota. The evidence is that berries are rich sources of polyphenols and so are likely to have a positive impact upon chronic diseases linked to gut health, particularly in older populations.
According to the Blueberry Council the benefits of blueberries extend beyond inflammaging.
Experiments have demonstrated an improved insulin response in blueberry-fed mice when compared to controls.
Further evidence for augmented cognitive function in animals and humans has been found.
There are also preliminary studies supporting a relationship between blueberry consumption and reduced growth in cancerous cells.
Polyphenol is found in a wide range of fruit and vegetables as well as nuts and pulses. Here are some of the top 100 food sources of polyphenol according to a study published in 20102.
Health risks of bacon and other processed meats hit the headlines.
I’ve been reading about the potential health risks linked to meat consumption for decades1. The evidence of a relationship between processed meat products in particular and serious illnesses including cancer has been established for many years. So recent and widespread calls to rid bacon and ham of nitrates comes as no surprise. In fact in some senses it feels like a long overdue and underwhelming response.
Needless to say The British Meat Processors Association stand by their bacon and maintain that nitrates are ‘authorised additives’. However the dispute over the risks and benefits of nitrates in processed meat begs the question, why don’t we do away with processed meats altogether? Meats are processed to modify the taste or extend the shelf life, products include bacon, sausages, hot dogs, salami, corned beef, beef jerky, ham as well as canned meats. Until we know more about the relative health risks of the different products it might be advisable to avoid them all.
The importance of the microbiome to human health is just starting to emerge, but our attitude to gut health hasn’t always been this enlightened.
Just a heads up for anyone interested in learning more about the changing relationship between humans and gut health. A short series The Gut Instinct: A Social History has been broadcast on BBC Radio 4 this week over five 15 minute episodes. At the time of writing the transmissions were still available on the BBC iPlayer here.
The concept was to explore how humans related to digestive processes and gut health across culture and time. There’s a lot of general information linked to the microbiome, some directly relevant to us today. The programme was written and presented by restaurant owner Tim Hayward and it seeks to offer an account relevant to a general audience, setting out major historical landmarks as well as important contemporary issues. Unusually for a British show we actually hear adults talking about bowel movements and human waste in a practical and informative manner. The five episode titles reflect the general content of the series (Gut Culture, A Window into the Gut, The Language of the Gut, The Disease of Civilisation and The Gut Speaks). Don’t expect much detailed science but I’d imagine anyone who tunes in to pick up some new morsels of gut knowledge, total listening time is just 75 minutes.
Diet is becoming a crucial factor in maintaining estrogen levels in post menopausal women.
Menopause and health, diet is crucial
The number of women living with the menopause is growing, therefore more people are at risks from illnesses connected with life after the menopause. A recent study investigating estrogen levels and gut health in post menopausal females found a relationship between microbial diversity (the different types of microbes) and circulating estrogen. The implications of this are huge because low estrogen is linked to a wide range of health issues. Typically the diversity of microbes in the human digestive system (gut microbiota) can be altered with changes to diet, for example a greater emphasis on plant based foods, and the use of probiotics and prebiotics. This suggests that women’s health generally, including fertility might be improved simply through alterations to diet.
One of the most important factors in the amount of circulating estrogens in women is the gut microbiome (the population of microbes in our gut). The greater the diversity of gut bacteria generally speaking the higher the levels of estrogen will be. Low levels of estrogen are associated with a wide range of illnesses in older women such as: obesity, cancer, polycystic ovary syndrome, heart disease and even cognitive function. It is suggested that bariatric surgery, fmt and medication (metformin) can alter the gut microbiome and therefore limit estrogen-driven disease. But the evidence suggests that changes to diet alone may be able to have a significant impact on estrogen levels
I’d like to highlight four of the issues raised by the research:
There appears to be a strong relationship between what women eat and levels of circulating estrogen.
Different treatments exist to increase estrogen, but dietary changes alone might deliver significant benefits.
The benefits of increased circulating estrogen through improved diet may be available to women of any age and might be linked to improved fertility.
This study reflects a general pattern in health seen in human microbiome research, that a healthy gut is linked to reduced risks of developing a wide range of illnesses.
Latest study links processed meat to increased risks of breast cancer.
Latest research confirms processed meat increases breast cancer risk
I generally have mixed feelings writing about lifestyle choices correlated with increased risks of cancer. I don’t think provoking people’s fear is usually beneficial and I don’t see my role as pushing people towards or away from things that I feel are important. Even as a vegetarian and now a non-strict vegan I have never found that scare tactics draw people into thinking about their own wellbeing or that of others. I do retain however a genuine sense of gratitude to the people that educated me about the relationship between diet, gut bacteria and mental and physical health. So if I highlight the latest research reviewing the dangers of eating processed meats it does reflect my own thoughts but I hope that it offers readers the opportunity to make an informed choice about what they eat.
An understanding of the health risks of eating animal products has been around for decades, and the scientific evidence of potential dangers linked to meat consumption increase week to week. The latest study to hit the media, reports that women who eat processed meat products such as bacon and sausages, have a 9% increased risk of breast cancer compared to women eating low levels of those products. This is not the first (nor the last I’ll bet) study that links meat with increased risks of developing cancer. But once you look into this issue further you realize that eating processed meat is a triple whammy! Firstly you have the statistically evidenced increased risk of breast cancer, secondly there are also greater risks of a wide range of other health problems. But also that while you’re eating potentially harmful animal products you are not consuming health supporting fresh fruit and vegetables.
As a society we know that the mass, unthinking consumption of animals and animal products isn’t helping us individually or benefiting the wider society. I’m an advocate of a healthy diet based primarily on plants, including fermented products. The indications are that even if you eat fresh fruit and vegetables alongside your processed meats, the benefits to your gut health are going to be limited. A final point to consider is that if we know that the type and quality of the food we eat affects our own health, what is the impact on us of the diet of the animals we consume? If animals are being reared in harsh unsanitary conditions, dependent on antibiotics for their survival and with poor quality fodder, should we be surprised if eating them increases our risks of poor health?
Evidence is mounting that there is a relationship between what we eat and dementia.
I trained as a cognitive scientist/neuroscientist originally because I wanted to know more about how people could lower their risks of developing dementia in general and Alzheimer’s disease (AD) in particular. My interest in fermentation comes from exposure to research indicating that gut bacteria is correlated to a range of physical and mental health conditions. That if you have too many or two few of certain types of microbes within your digestive tract, then you are more likely to experience better or worse health.
Imagine my interest then when I receive details of research that stated,
“All the results suggest that AD may begin in the gut.”
This conclusion from Hu, Wang and Jin appeared in their 2016 study Alzheimer’s disease and gut microbiota. Clearly if the results stand up and can be replicated this will change much of what we know about AD, and how it might be treated. There is a growing body of research that has linked AD to diet, it is widely discussed in the vegan and vegetarian communities. But Hu, Wang and Jin take the current thinking further; that AD is not just linked to what we eat per se’ but the prebiotic and probiotic effects of our diet. This research suggests that future treatments for AD are likely to come in the form of dietary or microbiotial interventions. The investigation covers a wide range of evidence, the scientists also draw attention to known links between gastrointestinal diseases and reduced cognitive function as well as Parkinson’s Disease and abnormal levels of gut microbes. If you’re puzzled as to how the gut influences the brain, look into the gut- brain axis.
As a general rule I’m cautious about the findings of academic studies dealing with complex areas of human health like AD. There are such a wide range of factors able to influence wellbeing that to isolate and demonstrate causality is not a simple matter. There is also evidence linking a number of other behaviours (meditation, mindfulness) to reduced risks of neurodegeneration. So that if there is a correlation between both meditation and gut bacteria with lower risks of developing AD, we need to think about how it might work.
Anyone who has been around the meditation community for a while may have noticed a few things about regular meditators. They tend to be relatively calm and their diet and lifestyle tends to be a little different from the mainstream. For example I’ve observed that meditators appear to smoke tobacco and drink alcohol less than the general population. Anecdotally I have found more vegans and vegetarians in the meditation community than my non-meditating friends. You can see from these speculative ideas that the relationship between gut bacteria and AD could hold up even given the evidence linking meditation to lower risks of neurodegeneration.
Whilst this study in isolation does not prove that AD begins in the gut, it signposts further areas of potential research. We now need to look for more specific evidence and ‘joined up’ explanations. It seems that there has never been a better time to think about the benefits of bringing fermented food into your diet and protecting your gut health as far as possible.