Today, travelling and relocating is easier than ever before; as our livelihoods adapt, so does our gut flora. The bacteria in our bodies vary not only based on our diet and lifestyle, but also depending on our ethnicity and geographical location. Here's what you need to know.

By Tea Vuckovic

Our gut is home to hundreds of different species of bacteria that help our body break down food and help it to fight and prevent diseases. Clinical studies have shown that diversity in the gut microbiome correlates with our health.¹ Diet, disease, ethnicity, and geography have a major impact on shaping the diversity of our microbiota.² With increased immigration and ever-evolving eating habits, our more fast-paced lifestyles are leaving their mark on our microbiome. That's why researchers have been looking at how our lineage impacts our microbiome, and what effect living an expat lifestyle, actually has on our microbial blueprint.

Native residents are less prone to developing diseases

First of all, it seems the microbiome differs among individuals of different ethnicities, according to new research from the Netherlands. In the study, the authors sampled 2,084 residents from the same urban area of Amsterdam, where six different ethnicities were represented. Turns out, differences in the microbial composition were far more explained by their ethinicity, compared to any other traits analyzed – including diet and metabolic disorders.

The results showed that members of the same ethnic group tend to share a greater number of common bacterias found in gut. 

Amongst the subjects studied, 21 common bacterias were found. The results showed that members of the same ethnic group tend to share a greater number of common bacterias found in gut. Moreover, it was revealed that native residents were less prone to developing type 2 diabetes (T2DM), metabolic syndrome and obesity.

Certain gut bacteria are heritable 

In addition, another recent research study from the United States supported the notion that the microbiome differs among ethnic groups. The team explored whether or not self-declared ethnicity correlates with gut microbiota composition across 1,673 healthy males and females. The results showed that the microbiome differences among different ethnic groups were consistent. Namely, 12 types of bacteria were shown to vary between ethnicities. Importantly, it has been shown that most of these bacteria are heritable and connected to human genomic variation.

The family Odoribacteriaceae and genus Odoribacter produce butyrate in the gut. Their deficiency has even been negatively associated with severe forms of Crohn's disease and Ulcerative Colitis.

Meanwhile, types of bacteria called Clostridiales, Odoribacteriaceae and Odoribacter families were shown to be more abundant in Caucasians and Hispanics compared to Asian-Pacific Islanders, while Veillonella was more abundant in African Americans, compared to Caucasians and Hispanics. Notably, the family Odoribacteriaceae and genus Odoribacter produce butyrate in the gut. Their deficiency has even been negatively associated with severe forms of Crohn's disease and Ulcerative Colitis. Something that complements indications that Asian-Pacific Islanders have higher tendencies for these diseases.⁴

Your gut is trying to fit in

Your diet, medical history, and living environment distinguish your microbiome from someone else. With ethnicity, diet and lifestyle are often closely intertwined. This is why people from different parts of the world tend to have more divergent bacteria. As we adapt to new environmental factors, our gut microbes start to shift almost immediately. Moving and trying to fit in can be stressful for your gut. Fortunately, we can manipulate our gut microbial composition through diet and lifestyle, as well as taking prebiotics and probiotics.⁵

Diversify your gut microbiome

The best way to maintain a healthy gut flora is by eating a wide variety of fresh whole foods, such as vegetables, fruits, whole grains, and legumes. What's more, one of the main food components that can impact our gut microbiota is dietary fiber. Lifestyle changes have altered our fiber intake, too. Ancient dietary regimes could reach 100g intake per day, while urban populations eat only 15g per day of fiber, which is lower than recommended.

Ancient dietary regimes could reach 100g intake per day, while urban populations eat only 15g per day of fiber, which is lower than recommended.

These food components can be absorbed after conversion into their basic units: amino acids, free fatty acids, and glucose. If a food has a strong and entangled matrix, this conversion into the basic unit becomes very slow and the nutrients become less bioavailable. Food with a rigid structure (intact plant cell walls, larger food particles, without thermal treatment)  have lower bioavailability and become a substrate for the microbiota.

Food with a rigid structure (intact plant cell walls, larger food particles, without thermal treatment)  have lower bioavailability and become a substrate for the microbiota.

Therefore, we cannot digest it by ourselves. Bacteria use it and produce energy, leaving the host (us) with a lower caloric intake. Of course, this is often a win-win situation for modern people, excluding infants and the malnourished.⁶ In conclusion, understanding how the microbiome correlates with ethnicity and migration can lead us to better personalise our lifestyles, by understanding how our lineage has shaped our core microbiome today. With the power in our hands, GUTXY is trying to make your gut feel like home.
References 
  1. Duvallet, C., Gibbons, S. M., Gurry, T., Irizarry, R. A., & Alm, E. J. (2017). Meta-analysis of gut microbiome studies identifies disease-specific and shared responses. Nature Communications, 8(1). doi:10.1038/s41467-017-01973-8 2. Prideaux, L et al. (2013). Impact of Ethnicity, Geography, and Disease on the Microbiota in Health and Inflammatory Bowel Disease. Inflammatory Bowel Diseases, 19(13), 2906–2918. doi:10.1097/01.mib.0000435759.055773. Deschasaux, M. et al., (2018). Depicting the composition of gut microbiota in a population with varied ethnic origins but shared geography. Nature Medicine. doi:10.1038/s41591-018-0160-1
  2. Brooks, A. W., Priya, S., Blekhman, R., & Bordenstein, S. R. (2018). Gut microbiota diversity across ethnicities in the United States. PLOS Biology, 16(12), e2006842.doi:10.1371/journal.pbio.2006842
  3. Vangay, P., Johnson, A. J., Ward, T. L., Al-Ghalith, G. A., Shields-Cutler, R. R., Hillmann, B. M., … Knights, D. (2018). US Immigration Westernizes the Human Gut Microbiome. Cell, 175(4), 962–972.e10.doi:10.1016/j.cell.2018.10.029
  4. Brooks, A. W., Priya, S., Blekhman, R., & Bordenstein, S. R. (2018). Gut microbiota diversity across ethnicities in the United States. PLOS Biology, 16(12), e2006842.doi:10.1371/journal.pbio.2006842
  5. Vangay, P., Johnson, A. J., Ward, T. L., Al-Ghalith, G. A., Shields-Cutler, R. R., Hillmann, B. M., … Knights, D. (2018). US Immigration Westernizes the Human Gut Microbiome. Cell, 175(4), 962–972.e10.doi:10.1016/j.cell.2018.10.029
  6. Ercolini, D., & Fogliano, V. (2018). Food Design To Feed the Human Gut Microbiota. Journal of Agricultural and Food Chemistry, 66(15), 3754–3758.doi:10.1021/acs.jafc.8b00456