What is the microbiota/microbiome?
The human body is home to a huge number of microorganisms including bacteria. On the skin surface, on the inside- they’re there. Far from simply being a sign of poor sanitation, they actually appear to play a crucial role in our health. So germaphobes, beware: excessive cleanliness won’t rid you of all microbes, but will likely throw the balance between health-promoting and health-hindering bacteria out.
Jump straight to how to improve your gut health section.
- A large amount of evidence shows there’s a link between a deficient human microbiota (microbial populations inhabiting the body) and impaired health (including a range of conditions from allergies to cancer, inflammatory and metabolic diseases)
- It’d appear technological, medical and lifestyle changes over the last couple of centuries have been a double edged sword: leading to a reduced burden of many diseases, improved life expectancy and quality of life on the one hand, while opening the door to impaired microbiota and associated diseases on the other
- A clear cause-effect relationship has yet to be identified due to a reliance on association and animal studies.
- Until a cause-effect relationship is proven (or otherwise), sensible steps you can take to improve the health of your gut microbiota include consuming more plants, fibre and prebiotics. Increased plant and fibre consumption will exert concrete health benefits independently of microbiome changes.
- Probiotics are likely safe but their effect varies according to a number of factors, so it is difficult to predict if and how they’d benefit you. Medical restoratives may be valuable to people with special requirements, but greater understanding of them is required to maximise their safety and tailor solutions to individual patients.
This whole community of various micro-organisms which inhabit the body is referred to as the microbiota. On a technical note, it has been easier to identify the microbial genes found in humans than each species of microbe that may be present in individual/s- we refer to this grouping of genes as the microbiome. Here we’ll be considering the microbiome of the digestive system, as it is one of our major microbial hot spots: an average gut hosts several trillion microbes.
Microbiota and the days of our lives
The composition of your microbiota changes throughout life, reflecting differences in environmental exposure, needs and health status.
Your initial microbiota comes courtesy of your mother- microbes have been found in healthy placenta, the amniotic fluid of preterm infants, and meconium (a babies’ first poop). The microbiota is further enriched through the natural birth process and breastfeeding (breastmilk contains micronutrients beneficial to healthy microbes). During “microbiological youth” (the first 3+ years of life) we keep building up our microbial ecosystem with critters needed for development.
Phot credit: Food photo created by prostooleh – www.freepik.com
With the end of breastfeeding/infancy, there is a significant change in the microbiome. It is generally accepted that after this point your microbiome composition remains relatively stable (however there’s a lack of long-term studies to prove this). In adulthood your microbial composition will also increasingly reflect the environment around you. Now, the most important role of your microbiota is protection from pathogens and ensuring homeostasis.
The next big shift occurs in old age: there is less diversity of microbes (some populations are weakened or die), and less stability. It appears this effects the immune system and other conditions. However, these changes are also associated with a lot of lifestyle, environmental and health factors, so it’s a bit of a chicken and egg scenario.
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Microbiota and its changing place in our world
Humans and microbes have co-existed since the beginning of humanity, to the benefit of both: we each assist the other in staying well and surviving. This relationship has been relatively harmonious and stable throughout history… but since the late 1800’s the balance of our microbial populations (particularly in developed nations) has changed vastly. Believe it or not, it’s estimated that over 50% of the diversity in our microbiome has been lost since that time. Meanwhile, less-developed societies have retained richer microbiomes.
A number of factors account for this. First, the improvements in sanitation, availability of clean drinking water and use of chlorination of the late 19th century. This certainly has improved our health overall, but to the detriment of healthy, necessary microbial populations such as Bifidobacterium spp, Faecalibacterium prausnitzii, and Akkermansia muciniphila (just three examples). Changes have accelerated further with practices such as widespread antibiotic use, C-sections and infant formula.
Photo credit: Medical photo created by kjpargeter – www.freepik.com
A couple of caveats regarding C-sections and formula feeding: it is clear they can deplete a child of healthy microbes and microbial diversity in the short term. Remembering that early life is a key time for development that can affect health much later in life, this is significant enough in itself. However there have been mixed results concerning long term impact, and further research in this area is required. In addition, there are definite situations in which C-sections and/or formula use is the best or only feasible choice for individuals involved, so it is not anyone’s place to judge a mother. However, the widespread use of these on a population level has had impacts, so our health systems perhaps would do well to reflect on its practices, support and education provision.
With these large and rapid changes after millennia of relative stability, it’s not surprising we haven’t adapted well. This alone should give some hint as to why disturbing the balance of your microbial population can have deleterious consequences for us. For more specific examples read Part 2 on Harnessing the Power of the Microbiome for health.
Why might your microbiome have changed over the course your life?
I’m the co-founder of Evidently Healthy, the resident biohacker and a marketer’s dream. As someone who believes you can’t put a price on health. I’m passionate about improving lifespan and health span. In my spare time I enjoy traveling, snowboarding, diving, podcasts, exercise and eating in and out. #Coffee-Lover Rating global coffee bean for years..