Your gut is home to an incredibly large community of bacteria/microbes that have a profound influence on every aspect of your health. This ranges from mood to immune system, to metabolism and weight. Therefore, it’s important to always maintain the health of the gut. An effective way to do this is through dietary means. Unfortunately, a number of people continue to consume a diet rich in processed and refined foods. As a result, this then results in the loss of essential bacteria that would otherwise keep us healthy.
For instance, in 2015, Tim Spector, professor of genetic epidemiology at King’s College London, asked his son Tom, a genetics student at the University of Aberystwyth, to partake in an experiment whereby he went on McDonald’s diet for ten days. The result? After just four days, Tim noticed that his son’s gut had experienced a significant drop in the number of beneficial microbes. Rather, he had lost around 40% of his microbiome (this is about 1400 types). A loss of that magnitude is definitely a cause for concern.
With that said, a lot of research has been invested in looking at how our diet can influence, as well as improve our gut microbiome. So, in an effort to better understand this link, it’s best to examine the gut, as well as the diet, of individuals who have been cited as having the healthiest, as well as the most diverse human gut microbiome in the world – the Hadza people of Tanzania.
Who are the Hadza people?
The Hadza, or the Hadzabe, are a tribe native to Tanzania living in the Central Rift Valley. They are thought of as one of the world’s last remaining hunter-gatherer tribes. They number at around 1 000 men, women, and children, with around 200-300 pure hunter-gatherers. The Hadzabe grow no food and practice no form of agriculture. Yet, researchers have found that they appear to exist without diabetes, colon cancer, colitis, Crohn’s disease, and even obesity.
The reason for this? It appears that their diet, which is essentially what they’re ancestors ate and is high in fiber and includes honey, berries, as well as baobab and meat from hunting, has quite the effect on their gut bacteria.
What has research found on the Hadza tribe and gut health?
Living with the Hadza people
In June 2017 when Tim Spector, Professor of Genetic Epidemiology at Kings College London, traveled all the way to Tanzania to trek and eat with the Hadza tribe for a period of three days. During this time, he made sure to regularly analyze his stool samples along the way.
Throughout the three days, Spector consumed tubers, wild honey, Kongorobi berries, and the baobab fruit as well as roasted porcupine. Additionally, he also joined the Hadza on their hunting and foraging forays. This was to ensure that he was exposed to all the microbes that Hadza normally encounters. He also avoided washing for those three days. After three days, Spector found that his gut bacteria had faced a 20% increase. He even acquired rare strains of bacteria. Furthermore, upon his return to England, his gut microbiome soon returned to what it had been before the three-day experiment. Nonetheless, the excursion highlighted how quickly the right diet can alter one’s gut microbiome.
The gut power of the Hadza diet
A 2017 study published in the journal Science, led by microbiologist Justin Sonnenburg of Stanford University, set out to examine the gut microbiome of the Hadza people, by paying particular attention to their stool samples, as well as their diets.
For the study, Sonnenberg and his team analyzed 350 stool samples from nearly 190 Hadza men and women. They did so over a period of about 18 months (this period included four seasonal changes). There were seven collection dates in all. The researchers then compared the stool samples to 17 other stool samples from populations across the globe. These included other hunter-gatherer communities in Venezuela and Peru and subsistence farmers in Malawi and Cameroon.
What were the results?
The researchers found that, compared to Americans, the Hadza people have a far more diverse gut microbiome. Sonnenburg and his team concluded that a person’s diet can have a profound influence on the diversity of their gut microbiome. They even believe that a Western diet is essentially affecting gut diversity. They feel that people living in the industrialized world are less likely to have a diverse gut microbiome, and this is then affecting their health.
“The challenge is to understand the importance of the ecological role and functional contributions of [microbial] species with which humans co-evolved but that are now apparently underrepresented or missing in industrialized populations,” explained the researchers.
The team also found that unlike industrialized populations, the diversity of gut microbiomes did not decline with age amongst the Hadza tribe.
The role of fiber
Additionally, Sonnenburg and his team also noted that the gut microbiome of the Hadza tribe changed, depending on the season. During the dry season, the Hadzabe eat a lot more meat, hunting games such as antelope. Yet during the wet season, they regularly forge more berries and honey. The only foods that they consumed year-round were tubers and the baobab fruit. The study found that during the wet season, their microbiome shifted yet during the dry season, the missing microbes returned. As of the time of publication, the researchers were unsure of exactly what caused the change in the gut microbiome.
That said, the researchers do admit that their intake of dietary fiber may influence the gut microbiome diversity of the Hadza people. As mentioned, the Hadzabe consume tubers, which are root vegetables incredibly high in fiber, all year round. As a result, they can consume around 150 grams of fiber each day. According to the researchers, this is 10 times more than what Americans consume.
“Over the past few years, we’ve come to realize how important this gut community is for our health, and yet we’re eating a low-fiber diet that totally neglects them,” Sonnenburg explained. “So we’re essentially starving our microbial selves.”
The verdict on the study
While the study is promising, Sonnenburg made sure to highlight a few tidbits. For one, his team has yet to determine just how well the Hadza gut microbiome is protecting them against chronic diseases, regardless of how rare the incidences are in the community. Additionally, he made sure to note that the low life expectancy for the Hadza, 46 years, is largely as a result of the high infant mortality rate and accidental deaths (such as falling out of a tree whilst collecting antioxidant-rich honey).
Furthermore, we may never catch up to the Hadza tribe in terms of microbiome diversity. This is because they are exposed to additional bacteria from the soil, the animals they hunt and from their lack of western hygiene.
However, that doesn’t mean we shouldn’t try. Sonnenburg and his team proved that the Hadza people altered their gut microbiome simply by changing their diet per season. Therefore, there’s no reason to why we can’t do the same.
Adopting the Hadza diet
The baobab fruit shouldn’t just be a staple food for the Hadza people. In fact, everyone should include baobab in their diets, be it in the form of powders or supplements.
Emerging from the baobab tree, the baobab fruit contains a healthy amount of essential nutrients. As a result, it has been linked to reducing the risk of diabetes, boosting digestive health, combating inflammation, and strengthening the immune system.
While it may be hard to get access to the baobab fruit, you can easily get baobab powder or supplements from your nearest health store.
Berries, berries and more berries
Kongorobi berries are small, slightly sweet berries that contain high amounts of both fiber and polyphenols – which are powerful plant-based compounds linked to protecting against chronic diseases (1).
However, as Kongorobi berries may be hard to find, you can opt for other health-boosting berries such as blueberries. Blueberries are loaded with fiber, and they’ve also been linked to a number of health benefits. These include regulating high blood pressure, reducing the risk of heart disease, and cancer as well as protecting the brain from degeneration.
Eating foods that are groping during their optimal season can serve to provide you with their nutritional content at the highest value. A study published in the International Journal of Food Sciences and Nutrition found that broccoli grown during the fall season (which is its peak season) contains higher amounts of vitamin C when compared to broccoli grown during spring. Also, foods consumed out of season often need to endure post-harvest treatments in order to be available year-round, and these artificially ripened foods are quite dense in nutrients (2).
Also, eating seasonally is much better for the environment as it reduces your carbon footprint as it reduces the environmental impact resulting from the long-distance that the food may have to travel before hitting the shelves.
As mentioned, the Hadza tribe makes sure to consume adequate amounts of fiber every day. Aside from promoting digestive health, a high-fiber diet encourages the production of more diverse and healthy gut flora, reduces cholesterol levels, regulates blood sugar levels and helps you maintain your weight.
Now, it wouldn’t be advisable to aim for 100 grams a day that the Hadza get. However, it’s important to at least consume 15 grams of fiber a day. Artichokes, Brussels sprouts, broccoli, kale, beets are each high in fiber. Additionally, you can also enjoy almonds, pistachios, pumpkin seeds, chickpeas, apples, and bananas.
Rich in a number of essential nutrients, honey is the perfect addition to your day. Thanks to its probiotic value, honey helps to promote a healthy gut. Additionally, it’s also been linked to promoting oral health, healthy sleep, cognitive function, as well as faster wound healing and killing off cancer cells.
The thought of consuming porcupine if you’re not part of the Hadza tribe may sound surreal. However, there are a few benefits of enjoying this delicacy. It’s low in fat and high in protein, amino acids as well as omega 3 fatty acids.
However, it is a delicacy thus it may not be for everyone’s taste buds. In that case, you can opt for salmon meat instead. It’s also low in fat and high in protein, omega 3 fatty acids, and other essential nutrients. That said, here’s a delicious salmon recipe you could try.
At the end of the day, our diet can affect the diversity and functionality of our gut microbiome. With that said, it’s important to ensure that we’re consuming a diet that’s beneficial to our gut health. In the case that we’re not, there’s no reason as to why we can’t simply adjust our diet for the sake of our gut, and overall health.