Do you have the guts to be a vegan?
It raises a myriad of questions for a vegan, when you start to think of your body as a microbiome. In fact, when you look in a mirror, one percent of the cells are yours and the other 90 trillion cells that are part of your body are micro bacteria and fungi.
Over the last decade, science has started to focus on the nature and role of our ‘inner ecosystems’ and many of the results have been unexpected.
‘… Researchers have demonstrated that the human body is not such a neatly self-sufficient island after all. It is more like a complex ecosystem—a social network—containing trillions of bacteria and other microorganisms that inhabit our skin, genital areas, mouth and especially intestines.’
The picture that is emerging is that approximately 1.5kg of bacteria live inside our guts and are a crucial part of our immune systems and health. While they assist with digestion, they are also part of the neuronal system and assist in the prevention of disease. This is the continuing mission of the NIH human microbiome project or The British Gut Project to map the types of micro-organisms that are part of our bodies.
A bigger gut from having a bad gut
A healthy gut has also been linked to the rise of obesity. This is in part driven by the western diet; Dr Martin Blaser discusses this book ‘Missing Microbes’. His hypothesis is that the overuse of antibiotics, c-sections, and antiseptics has permanently changed our microbiome and are causing an increase in modern diseases such as obesity, juvenile diabetes, and asthma.
Interestingly, some of his insights came from speaking to farmers, relating to why they use so many antibiotics. In this industrialised-production of animals, the answer was very commercial
Ranchers and farmers have been feeding antibiotics to the animals we eat since they discovered decades ago that small doses of antibiotics administered daily would make most animals gain as much as 3 percent more weight than they otherwise would. In an industry where profits are measured in pennies per animal, such weight gain was revolutionary.
It should be no surprise with the ‘over prescription’ of antibiotics and the amount of antibiotics in the food-chain that obesity is such a modern preventable epidemic – which remains the number one health issue facing the developing world. Globally, there are more than one billion overweight adults and at least 400 million of these are obese. Furthermore, more than 40 million children, under the age of five, were overweight in 2010.
A gut instinct is always right.
We haven’t really understood our gut. In recent times it’s clear that they have many more functions than we previously envisaged. The stomach and gut are now recognised as having taste receptors – a role that we previously thought was reserved exclusively for the tongue.
This picture has become more complex, with our gut now being called our ‘second brain’. It produces more of the neurotransmitter serotonin than your brain does, which is known to have a beneficial influence on your mood. As the old maxim goes, the way to man’s heart is his stomach.
There is growing evidence that psychiatric disorders can be associated directly with bowel disorders. Michael Berk, a professor of psychiatry at the Deakin University School of Medicine in Australia states that “the results are unusually consistent, and they show a link between diet quality and mental health.” James Greenblatt links the psychiatric health of patients to diet and their stomach microbes. He makes the observation that “There are more neurons in the GI tract than anywhere else, except the brain.” A similar perspective has been made by Emeran Mayer, professor of physiology, psychiatry and bio-behavioral sciences at the University of California, “The system is way too complicated to have evolved only to make sure things move out of your colon”.
My gut tells me
The nature of this second brain might be more of a shared-brain than one of our own. There is evidence that bacteria send out signals to the body, encouraging it to consume the food on which it thrives. Dr Carlo Maley explains
‘Bacteria within the gut are manipulative…There is a diversity of interests represented in the microbiome, some aligned with our own dietary goals, and others not.’
This is another way that bacteria might be influencing the obesity epidemic by preferring fats and sugar, highlighting the need to maintain a healthy flora balance.
A recent study has shown that eating junkfood, kills stomach bacteria which protect against obesity, diabetes, cancer, heart disease, inflammatory bowel conditions and autism
Planting a better microbiome
It’s clear that what we eat influences the composition of our microbiome – much of the evidence points to the benefits of eating a plant-based diet.
Dr Jane Muir, Head of Translational Nutrition Science at Monash University’s Department of Gastroenterology. Another important group of fibres -called short-chain oligosaccharides – are found in nuts, seeds, onions, garlic, Jerusalem artichokes and, watermelon, as well as legumes and grains.
“These fibres feed other friendly microbes that produce fatty acids that are absorbed into our bloodstream and which may be important for reducing inflammation – meaning the kind of low grade chronic inflammation in the body that contributes to problems like heart disease and diabetes,”
An easy way of getting more of these fibres is by eating legumes and wholegrains – but these are also foods that some people have struck off the menu, including anyone who’s avoiding grains containing gluten or who’s following the Paleo Diet which excludes both grains and legumes.
Tim Spector, professor of genetic epidemiology at King’s College London.
Excluding fat and sugar are less important to a healthy diet than making sure the food one eats is as diverse and natural as possible, Professor Spector said.
His advice chimes with studies suggesting that Belgian Beer, garlic, coffee, leeks and celery are ideal foods for promoting healthy gut flora.
Michael Berk, believes that diets that are not modern appear to be the most beneficial
“Traditional diets — the kinds of foods your grandmother would have recognized — have been associated with a lower risk of mental health issues,” Berk said. Interestingly, that traditional diet may vary widely across cultures, including wheat for some people but not for others; the common element seems to be whole, unprocessed, nutrient-dense foods.
A study by Marian Glick-Bauer and Ming-Chin Yeh have connected a vegan’s microbiome to being healthier
The vegan gut profile appears to be unique in several characteristics, including a reduced abundance of pathobionts and a greater abundance of protective species. Reduced levels of inflammation may be the key feature linking the vegan gut microbiota with protective health effects.
Other studies show the impact of meat and dairy on your gut as being pronounced and detrimental.
Switching to a diet packed with meat and cheese — and very few carbohydrates — alters the trillions of microbes living in the gut, scientists report Wednesday in the journal Nature.
The change happens quickly. Within two days, the types of microbes thriving in the gut shuffle around. And there are signs that some of these shifts might not be so good for your gut: One type of bacterium that flourishes under the meat-rich diet has been linked to inflammation and intestinal diseases in mice.
While this is a new frontier for science, there is emerging evidence that a vegan diet is beneficial towards a flourishing benevolent 1.5kg colony in your gut. With a range of physical and mental benefits, you’d be nuts not to be vegan.
Cover image from here