Updated: Aug 7
The human body is a complex ecosystem home to trillions of microorganisms that have allowed us to evolve into the species we are today.
The good news is, our body’s microscopic residents are anything but free loaders. The following is a list of bodily processes proven to be influenced by the human microbiome:
Development of immune, respiratory, and neuroendocrine systems
Production of neurotransmitters, vitamins and nutrients
Breaking down drugs and toxins
Protection from infection, inflammation, and other immune disorders
The list goes on. With each study, scientists are expanding our knowledge on the way our microbiome influences so many different aspects of our health.
Microbiota vs. Microbiome
Although the average person doesn’t need to stress too much about understanding the difference between these two terms, we thought some readers might appreciate the distinction.
There are thousands of different species of bacteria, archaea, fungi, viruses and protozoa that may reside on and within us. This composition of microorganisms varies from person to person based on factors such as culture, environment, maternal microbiota, diet, drug and toxin exposure, genetics, and immune system.
Dysbiosis is when our body's microorganisms become imbalanced. For example, if a species that normally makes up a large part of our gut becomes scarce and others more dominant.
Microbiomes of the Human Body
Below are a few of the more commonly known microbiomes in the human body.
The gut microbiome is the body’s most diverse community of bacteria, viruses, and fungi. More than 90% of the cells that make up the gut are actually microorganisms
Digestion, immune and endocrine functions are executed by the gut and it's resident microbes.
Gut microbiota are critical to the development of the immune and neuroendocrine system.
Many diseases such as obesity and inflammatory bowel disease are a result of lacking diversity of the gut microbiome.
The oral microbiome comes in next in line in terms of diversity. The mouth is home to at least 700 species living on the hard surfaces of teeth and the soft tissues.
The lower organs, the brain, and one’s behavior are impacted by the health of the microbiome.
Dysbiosis results in oral diseases such as cavities, gingivitis and periodontitis, and may play a role in neurodegenerative diseases.
Smoking, excessive antibiotic use, and consumption of sugary or acidic drinks contribute to dysbiosis.
The skin microbiome is composed of millions of bacteria, fungi, and viruses, and is as unique as our fingerprints. The skin microbiome of a healthy adult experiences little change over time.
The microorganisms on our skin are the first line of defence against pathogens in our environment.
These organisms play a role in immune function and development.
Dysbiosis of skin microbiota can cause skin disorders such as eczema or psoriasis.
The vaginal microbiome is essential to the health of the female reproductive system. Unlike many of the body’s other microbial communities, the vaginal community is simplistic in its diversity.
Species of Lactobacillus tend to dominate healthy vaginal microbiota. Their name relates to the lactic acid these bacteria produce that keep the vaginal pH stable.
The microorganisms of the vagina work to prevent the colonization of pathogens that may cause bacterial vaginosis, yeast infections, sexually transmitted infections, and urinary tract infections
Healthy vaginal microbiota is also important if you are or plan to become pregnant. The species present in this part of your body will be passed onto your baby.
From Dysbiosis to Disease
The industrial revolution marked a drastic change in the foods we eat, the water we drink, and the way we treat our bodies and our environment. With these changes, a major shift in the human microbiome has occurred that coincides with a major shift in the diseases and disorders affecting us.
Our beneficial bacteria play a role in digestion, immunity, mental health, and more. Here are just a few of the diseases and disorders that have been linked to dysbiosis:
When we think of wellness we must consider the relationship we share with these tiny beings. If we provide a safe space and ample food for our body’s residents, they will help us live happy and healthy lives. The environment we provide both inside and outside of our body is critical to maintaining this symbiotic relationship.
The hygiene hypothesis suggests countries with extensive sanitizing practices, such as refrigeration, pasteurization, water treatment, and food processing, result in populations with underdeveloped microbiota. When it comes to promoting the health of our microbiome, it appears there is such a thing as TOO clean.
A Diverse Diet for a Happy Microbiome
What we put into our body is one of the biggest factors in the well being of our gut. Prebiotics and probiotics are both great options for improving your gut microbiome. We’ve all heard of probiotics, but many of us aren’t aware of prebiotics.
Before you shell out for an expensive probiotic, make sure you are creating a safe and nurturing space for these beneficial bacteria to thrive.
Eat 30-40 different types of fruits, veggies, and other plant products per week (different colors and varieties count).
Enrich your diet with prebiotic foods like flaxseed, onions, wheat bran and jerusalem artichoke.
If you are struggling to incorporate enough diversity into your diet, prebiotic supplements in the form of powdered greens can be a great option.
Adding a few fermented foods and drinks to the weekly menu is a great way to expose your gut to new microbes.
Eat organic when you can. The pesticides found on foods that aren’t organic have the potential to do some serious damage to your microbiome.
If consuming alcohol, practice moderation, as excessive alcohol intake can cause your microbiome to experience dysbiosis.
Regular breath-work and exercise will help reduce stress, which can throw off your beneficial bacteria.
Finding a Quality Probiotic
Walk into any health food store today and you may feel overwhelmed by the choices when it comes to probiotics. There are so many brands advertising varying quantities, strains, and health claims.
The commercial sale of probiotics is a $40 billion industry and growing. How do we find the one that will really work? The truth is not all probiotics are created equal, but there are a few guidelines that will make your choice a bit easier:
Look for probiotics with a minimum of 1 billion colony forming units (CFU).
Make sure the labeling states that these CFUs are alive and active.
Pick a brand with a "time release capsule" to make sure the probiotic doesn’t die the moment it hits your stomach acid. With a time-release capsule, the capsule will survive through the stomach into the intestinal tract and be released slowly throughout it over time.
The most common and well researched strains are Lactobacillus, Bifidobacterium, and Saccharomyces, this is a good place to start.
If you are looking to treat a specific condition speak to your healthcare provider and do some research to find out what strains will be best for you.
Gut health is so much more than just an expensive probiotic, and one should apply as many of the lifestyle and diet practices discussed above in addition to adding a probiotic supplement.
If you have a story about an experience with dietary or lifestyle changes helping you overcome health issues related to dysbiosis we would love to hear from you! Check our forum for threads related to this topic or feel free to get the conversation going yourself.
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