With the summer approaching, many of us will be preparing to get back to nature. From heading to the cottage to camping to taking that dream of a lifetime vacation to a remote location on an island or in the jungle, there is an urge to return to our evolutionary roots and find harmony with the uncivilized world.
The goal of becoming 'natural' may seem achievable, yet there has been no way to actually tell if there is any success. But now, there is a way to tell if you are truly becoming one with Mother Earth. The answer lies on your hands.
Last week an American team of researchers published a paper in which they looked at the microbial content of human hands. They focused on two distinct populations; one from the United States and the other from the African country of Tanzania. They not only found distinct differences in the bacteria between the two groups, but they were also able to identify quite possibly a new way to test for a truly natural being or a Westernized wannabe.
The idea of using microbiological variances between populations to understand social differences is not entirely new. Since the beginning of the microbiome era, researchers from around the world have been attempting to understand our human differences based on changes at the microscopic level. Over the years, a great deal has been learned, although in some cases, the results provided more questions than answers. Yet as the number of studies grew, a better understanding was developed.
One of the first microbiome diversity studies was back in 2007, a European study found children raised either on a farm or in private schools had different gut microbiota. The impact of their diet and lifestyle were important factors in the diversity although the authors could not provide particularly good links between specific bacteria and lifestyle choice.
The authors found a significant difference between the types of microbes found and their relation to diet. In European populations, where diets are primarily easy-to-digest sugars, starches and proteins, the bacteria were predominantly sugar-based fermenters and potential pathogens.
In contrast, those from Burkina Faso eat higher levels of dietary fibre and other digestive-resistant starches; they had mainly starch-digesters with few to no pathogens. This went against the original assumption factors such as sanitation, hygiene, geography and climate played a role in microbiome development. From their perspective, diet was the major, if not the sole contributing factor.
This striking result led another team of international researchers to determine if this diversity in the microbiome could last from childhood to adulthood. They looked at the microbial composition of individuals from three different populations, one from the United States, from Venezuela and from Malawi. The age range was between infancy to 70 years. When the team looked at the nature of the microbes, they expected to see a similar difference, regardless of age. What they found was a complete surprise.
Although the authors showed the same difference as the 2010 study for children of the same age, there was much more to the story. At earlier time points in life, there was almost no difference between the samples; they all had similar microbiomes. But then, as each person aged, the microbial diversity increased both between the populations as well as within them.
From their calculations, no matter where a person is born, he or she will have a similar microbial population to everyone else. Then, with age, the person acquires a unique profile, a microbial fingerprint. The changes reflected not only diet, but also lifestyle, including social, cultural and even religious traditions. Unlike the 2007 and 2010 studies, the impact of diet appeared to be less significant than originally thought.
This paradox between the two studies was a driving force in the design of last week's study on hands. In order to avoid dietary complexities, the authors stayed away from the gut and focused on a part of the body completely independent of food choice. Moreover, because of the assumed similarity amongst children, the team took samples -- hand washings -- from adults.
Not surprisingly, the data revealed a difference between the American and Tanzanian hands. The nature of the bacteria on the hands of the U.S. population was consistent with other samplings. Analysis of the bacteria on Tanzanian hands, however, revealed a few surprises. The traditional 'skin bacteria' was noticeably absent and instead was comprised of a number of soil bacteria not normally associated with humans. Even more interesting was the fact some of these bacteria were considered to be pathogenic to humans; in this case, they were not. Further analysis of the bacteria found revealed many were known to have a symbiosis with plants to keep them safe from disease. Unfortunately, the authors did not determine if such mutualism existed with people.
The overall outcome of the study revealed a significant difference between not only the populations, but their activity as well. The Tanzanians tested were completely integrated with nature. They lived in open-air dwellings; they were continually outside for work, chores or play; and they were exposed to natural sources of water and food. Their natural way of life provided them with an honest-to-goodness natural microbiome.
The data of the study also revealed another very important aspect of human social behaviour from which many of us can learn. Though many of us would tend to believe we are environmental, our hands dictate that we are anything but. Our Western, industrialized, processed world has turned our lives and our microbiomes away from nature. While changing to a Tanzanian-style of life may not be prudent or possible, we can learn to at least bring a little more nature into our lives. From planting a garden to going out and enjoying the rural world, we can do a little more to bring natural microbes back into our lives. With the warmer weather here, it's the perfect time to start.