Jul 5th 2017

I spent three days as a hunter-gatherer to see if it would improve my gut health

by Tim Spector and Jeff Leach

Tim Spector, in the picture above right, is Professor of Genetic Epidemiology, King's College London Jeff Leach is Visiting Research Fellow, King's College London
File 20170629 29069 1yxvqga Jeff Leach, Author provided

Mounting evidence suggests that the richer and more diverse the community of microbes in your gut the lower your risk of disease. Diet is key to maintaining diversity and was strikingly demonstrated when an undergrad student went on a McDonald’s diet for ten days and after just four days experienced a significant drop in the number of beneficial microbes.

Similar results have been demonstrated in a number of larger human and animal studies.

Your gut microbiome is a vast community of trillions of bacteria that has a major influence on your metabolism, immune system and mood. These bacteria and fungi inhabit every nook and cranny of your gastrointestinal tract, with most of this 1kg to 2kg “microbe organ” sited in your colon (the main bit of your large intestine).

We tend to see the biggest diet-related shifts in microbes in people who are unhealthy with a low-diversity unstable microbiome. What we didn’t know is whether a healthy stable gut microbiome could be improved in just a few days. The chance to test this in an unusual way came when my colleague Jeff Leach invited me on a field trip to Tanzania, where he has been living and working among the Hadza, one of the last remaining hunter-gatherer groups in all of Africa.

Hadza hunters. Jeff Leach, Author provided

My microbiome is pretty healthy nowadays and, among the first hundred samples we tested as part of the MapMyGut project, I had the best gut diversity – our best overall measure of gut health, reflecting the number and richness of different species. High diversity is associated with a low risk of obesity and many diseases. The Hadza have a diversity that is one of the richest on the planet.

The research plan was devised by Jeff who suggested I should have an intensive three days of eating like a hunter gatherer during my stay at his research camp. I would measure my gut microbes before heading to Tanzania, during my stay with the Hadza, and after my return to the UK. I was also not allowed to wash or use alcohol swabs and I was expected to hunt and forage with the Hadza as much as possible – including coming in contact with the odd Hadza baby and baboon poo lying about.

To help us record the trip I was accompanied by Dan Saladino, the intrepid presenter and producer of BBC Radio 4’s The Food Programme, who was preparing a Hadza microbe special.

After a long tiring flight to Mount Kilimanjaro Airport in Tanzania, we stayed overnight in Arusha, a city in the north of the country. Before setting off the next morning, I produced my baseline poo sample.

After an eight-hour journey in a Land Rover over bumpy tracks, we arrived. Jeff beckoned us to the top of a huge rock to witness the most amazing sunset over Lake Eyasi. Here, within a stones throw of the famous fossil site of Olduvai Gorge and with the stunning plains of the Serengeti in the distance, Jeff explained that we were never going to be closer to home as a member of the genus Homo, than where we were standing at that moment.

The million-year-old diet

The Hadza seek out the same animals and plants that humans have hunted and gathered for millions of years. Importantly, the human-microbe tango that played out here for aeons probably shaped aspects of our immune system and made us who we are today. The significance of being in Hadza-land was not lost on me.

Unlike the Hadza, who sleep around the fire or in grass huts, I was given a tent and told to zip it up tight as there were scorpions and snakes about. I had to be careful where I stepped if I needed a nocturnal pee. After an interesting but restless night’s sleep, a large pile of baobab pods had been collected for my breakfast.

The baobab fruit is the staple of the Hadza diet, packed with vitamins, fat in the seeds, and, of course, significant amounts of fibre. We were surrounded by baobab trees stretching in the distance as far as I could see. Baobab fruit have a hard coconut-like shell that cracks easily to reveal a chalky flesh around a large, fat-rich seed. The high levels of vitamin C provided an unexpected citrus tang.

The Hadza mixed the chalky bits with water and whisked it vigorously for two to three minutes with a stick until it was a thick, milky porridge that was filtered – somewhat – into a mug for my breakfast. It was surprisingly pleasant and refreshing. As I wasn’t sure what else I would be eating on my first day, I drank two mugs and suddenly felt very full.

My next snacks were the wild berries on many of the trees surrounding the camp – the commonest were small Kongorobi berries. These refreshing and slightly sweet berries have 20 times the fibre and polyphenols compared with cultivated berries – powerful fuel for my gut microbiome. I had a late lunch of a few high-fibre tubers dug up with a sharp stick by the female foragers and tossed on the fire. These were more effort to eat - like tough, earthy celery. I didn’t go for seconds or feel hungry, probably because of my high-fibre breakfast. No one seemed concerned about dinner.

Hadza women lightly roasting starch and fibre-rich //ekwa tubers. Jeff Leach, Author provided

A few hours later we were asked to join a hunting party to track down porcupine – a rare delicacy. Even Jeff hadn’t tasted this creature in his four years of field work.

Two 20kg nocturnal porcupines had been tracked to their tunnel system in a termite mound. After several hours of digging and tunnelling – carefully avoiding the razor-sharp spines – two porcupines were eventually speared and thrown to the surface. A fire was lit. The spines, skin and valuable organs were expertly dissected and the heart, lung and liver cooked and eaten straight away.

Hadza hunter walking back to camp with a dispatched porcupine flung over his shoulder. Jeff Leach, Author provided

The rest of the fatty carcass was taken back to camp for communal eating. It tasted much like suckling pig. We had a similar menu the next two days, with the main dishes including hyrax – a strange furry guinea-pig-like hoofed animal, weighing about 4kg – a relative of the elephant, of all creatures.

Harvested high from a baobab tree, our dessert was the best golden orange honey I could ever imagine – with the bonus of honeycomb full of fat and protein from the larvae. The combination of fat and sugars made our dessert the most energy-dense food found anywhere in nature and may have competed with fire in terms of its evolutionary importance.

In Hadza-land nothing is wasted or killed unnecessarily, but they eat an amazing variety of plant and animal species (around 600, most of which are birds) compared with us in the West. My other lasting impression was how little time they spent getting food. It appeared as though it took just a few hours a day – as simple as going round a large supermarket. Any direction you walked there was food – above, on and below ground.

Massive increase in microbiome diversity

Twenty-four hours later Dan and I were back in London, him with his precious audio tapes and me with my cherished poo samples. After producing a few more, I sent them to the lab for testing.

The results showed clear differences between my starting sample and after three days of my forager diet. The good news was my gut microbal diversity increased a stunning 20%, including some totally novel African microbes, such as those of the phylum Synergistetes.

The bad news was, after a few days, my gut microbes had virtually returned to where they were before the trip. But we had learnt something important. However good your diet and gut health, it is not nearly as good as our ancestors’. Everyone should make the effort to improve their gut health by re-wilding their diet and lifestyle. Being more adventurous in your normal cuisine plus reconnecting with nature and its associated microbial life, may be what we all need.


This article was originally published on The Conversation. Read the original article.

Browse articles by author

More Essays

Jul 10th 2019

 

The eight-mile ‘river of flowers’ that grows alongside a motorway nea
Jul 5th 2019
"........since World War II, 97% of unimproved grassland habitats have vanished from the UK. This has contributed to the loss of pollinating insects – and the distribution of one third of species has shrunk since 1980."
Jun 25th 2019
"For many of us, eating a meal containing meat is a normal part of daily life. But if we dig deeper, some sobering issues emerge. Every year, 66 billion terrestrial animals are slaughtered for food. Predictions are that meat consumption will rise, with increasing demand for meat from China and other Asian countries as their standards of living increase. The impact of grazing animals on the environment is devastating. They produce 18% of the world’s greenhouse gases, and livestock farming is a major contributor to species extinctions."
Jun 22nd 2019
"Throughout history, people who have gained positions of power tend to be precisely the kind of people who should not be entrusted with it. A desire for power often correlates with negative personality traits: selfishness, greed and a lack of empathy. And the people who have the strongest desire for power tend to be the most ruthless and lacking in compassion."
Jun 21st 2019
"In this era of Trump, it should perhaps come as no surprise to find supposed experts lacking in historical perspective. Yet it is still disappointing to find this deficit in the New York Times, which prides itself on clinging to a pursuit of the truth. So it is a bit sad to read the plaintive cry of Allison Schrager’s op-ed of May 17, lamenting that the domination of art markets by the super-rich will somehow force smaller galleries to go out of business, and imperil the careers of young artists."
Jun 17th 2019
Extract: "ust as an earlier generation resisted the limiting post-War era "white middle class" definition of being American by giving birth to an awakening of cultural pluralism and ethnic pride, it falls to our generation to fight for an expanded view of the idea of being American that rejects the narrow view projected by Trump and white nationalists. The idea of America isn't theirs. It's bigger than they are and unless our national cohesion is to unravel, this challenge must be met by projecting an inclusive vision of America that celebrates our inclusive national identity in an increasingly globalized world."
May 28th 2019
Whatever other attributes Homo sapiens may have – and much is made of our opposable thumbs, upright walking and big brains – our capacity to impact the environment far and wide is perhaps unprecedented in all of life’s history. If nothing else, we humans can make an almighty mess.
Apr 29th 2019
A century ago, unspeakable horrors took place on every continent that were known only to the victims and the perpetrators. Not so today. As a result of advances in communications – from the telegraph and radio to satellite television and the internet – the pain and loss of global tragedies are brought home to us in real time.   Because of this expanding consciousness, the post-World War II era has witnessed the rise of visionary leaders and the birth of countless organizations dedicated to alleviating suffering and elevating the causes of peace, human rights, and tolerance among peoples. Individually and collectively, they have championed the rights of peoples in far-flung corners of the world, some of which had been previously unknown to those who became their advocates. These same leaders and groups have also fought for civil rights and for economic, social, political, and environmental justice in their own countries. 
Apr 23rd 2019

 

“Cursed be that mortal inter-indebtedness which will not do away with ledgers. I would be free as air; and I’m down in the whole world’s books. I am so rich… and yet I owe for the flesh in the tongue I brag with” (Moby Dick, chapter cviii). 

Apr 20th 2019
Economists speak in numbers only, clinging to statistical data and quantitative models. We do so in the hope of looking objective. But this is counter-productive – “data” cannot tell us everything. Other social sciences such as sociology and anthropology use a broader range of methods, and consequently have a broader perspective on society. If we take our societal role of adviser on economic matters seriously, we will need to open up and adopt the insights that these other disciplines bring us about how the economy works.Politics and economics are inextricably intertwined, as Adam Smith, David Ricardo, Karl Marx knew all too well. Somehow this has been forgotten. This does not mean economists need to get political or choose sides. But it does mean that we ignore politics at our own peril – by blindsiding ourselves or dismissing it as “external stuff”, we hamper our understanding of the very system we study.
Apr 16th 2019
Although it is not likely that many visitors who pass by the Giacometti sculptures on their way to Las Meninas will ponder it, the contrast between these works underscores the single greatest transformation in the history of western art, from a regime in which artists tailored their works to the aims of individual patrons, to one in which artists choose their techniques and motifs according to their own concerns, and only then present the products to an anonymous competitive market
Apr 4th 2019
On March eleventh, the world lost someone who was very special, who made a mark and touched people with his voice, as a singer, a humorist and writer..........I had the great good fortune to know him and spend time with him, playing music, talking with him – he was a man of immense culture, fluent in Hebrew, German, English, and Romanian. He loved New York City and Vienna and we would often swap apartments so that he could stay in New York while I lived at his place in Vienna.
Apr 1st 2019
The ongoing controversy over admissions to American universities has overlooked the one of the most telling aspects of the scandal—that it took place with the connivance and active participation of administrative bureaucracies able to act with impunity in the pursuit of their interests. Neither the professoriate, often the target of opprobrium from the left and the right, nor the student body, also the target of criticism from both sides of the political spectrum, bore any of the responsibility.  Current debates over “what ails” U.S. colleges and universities consistently ignore the single most important dynamic of all institutions—their structure of power. I suggest that the way in which power is allocated within American universities is strikingly similar to that of Soviet-type regimes. Presidents, chancellors, provosts, deans, and their bureaucratic apparatuses preside over vast real-estate and financial holdings, engage in the economic equivalent of central planning, have inordinate influence over personnel, and are structured hierarchically, thereby forming an enormously powerful “new class” like that described by the renowned Yugoslav dissident, Milovan Djilas, in the mid-1950s. 
Mar 22nd 2019
When you think of religion, you probably think of a god who rewards the good and punishes the wicked. But the idea of morally concerned gods is by no means universal. Social scientists have long known that small-scale traditional societies – the kind missionaries used to dismiss as “pagan” – envisaged a spirit world that cared little about the morality of human behaviour. Their concern was less about whether humans behaved nicely towards one another and more about whether they carried out their obligations to the spirits and displayed suitable deference to them. Nevertheless, the world religions we know today, and their myriad variants, either demand belief in all-seeing punitive deities or at least postulate some kind of broader mechanism – such as karma – for rewarding the virtuous and punishing the wicked. In recent years, researchers have debated how and why these moralising religions came into being.
Mar 19th 2019
European food and ingredients have become staple food choices for the British. The use of ingredients such as garlic, peppers, avocados, Parmesan cheese and all those other European ingredients that are now taken for granted are relatively new and were still rare in the 1990s. When I was growing up in rural Devon in the 1970s, olive oil was only really readily available in chemists as a cure for earache – now it is found in most food cupboards. And wine drinking has permeated through all social classes.
Mar 12th 2019
The Guggenheim’s strange and wonderful exhibition of Hilma af Klint’s groundbreaking, yet largely unknown body of abstract art is an important event – one that challenges us to not only rethink the early history of twentieth century abstract art, but to recognize her vision of art and reality as unique, authentic, and deliciously puzzling. 
Feb 25th 2019
Looking at the world today, it's clear that the consequences of this imperial legacy are still with us. If anything has changed it is that we are now beyond just viewing the former "natives" as far-away oddities. They are now living within our borders, having come to find the opportunities they were denied at home. So when I hear the reactions in the West to the influx of South Asians going to the UK, or North Africans going to France, or Central Americans migrating to the US, I can only say "Guys, these are the fruits of your conquest – your chickens coming home to roost."
Feb 25th 2019
Extracts: "The new novel Sérotonine by Michel Houellebecq, the bad boy of French literature, is a saga of depression and death told with such irony and wit that readers seem to love it despite the unsettling themes. Maybe it’s just me but I found myself laughing out loud.......True to form, the French don’t agree on Houellebecq – or anything else, for that matter. The impact of his new novel has divided the readers into opposite love-hate camps with hardly any middle ground. Houellebecq cannot leave you indifferent, notes a literary friend of mine"........Picture: Michel Houellebecq, by the reviewer Michael Johnson. 
Feb 19th 2019
The term “smiling depression” – appearing happy to others while internally suffering depressive symptoms – has become increasingly popular. Articles on the topic have crept up in the popular literature, and the number of Google searches for the condition has increased dramatically this year. Some may question, however, whether this is actually a real, pathological condition. While smiling depression is not a technical term that psychologists use, it is certainly possible to be depressed and manage to successfully mask the symptoms. The closest technical term for this condition is “atypical depression”. In fact, a significant proportion of people who experience a low mood and a loss of pleasure in activities manage to hide their condition in this way. And these people might be particularly vulnerable to suicide.
Feb 19th 2019
Outstanding, experienced journalist Michael Johnson, whose articles, often accompanied by his striking portraits, has now brought his love of music and of pen, ink, gouache and watercolor to create a study of remarkable insight, strong opinions and beauty in this gorgeous book. Written in both French and English the brief descriptions of musicians he has met, studied, interviewed are accompanied by distinctive portraits that, as his title suggests, some may be caricatures. I argue that the author/artist has created insightful studies of the human face engaged in the pursuit of music. The only caricature is his own self-deprecating, slyly wry self-portrait that opens the book—and it is worth the book’s purchase on its own.