Why You're Covered in Bacteria - the Microbiome

Jan 09, 2024

Why You're Covered in Bacteria - the Microbiome

Microbiome and its Importance in our Health

The human microbiome is a complex ecosystem of trillions of microorganisms living in and on our bodies, including bacteria, viruses, fungi, and other microbes. According to a report by the National Institutes of Health (NIH) Human Microbiome Project, humans are host to over 100 trillion microbial cells, outnumbering human cells by a ratio of about 10 to 1. These microorganisms play a crucial role in maintaining our health. They aid digestion, produce specific vitamins, regulate our immune system, and protect against harmful bacteria. Research has found correlations between changes in the microbiome and numerous health conditions, including obesity, diabetes, asthma, and even mental health disorders like depression and anxiety. A study suggested that the diversity and balance of our microbiome could be as important to our health as the genetic sequence of our DNA.


Difference between Microbiota and Microbiome

Though often used interchangeably, there is a subtle distinction between the terms' microbiota' and 'microbiome.' The microbiota refers to the 10-100 trillion symbiotic microbial cells harbored by each person, primarily bacteria in the gut; the term includes bacteria, archaea, protists, fungi, and viruses. The microbiota varies vastly from one individual to another in terms of species diversity. This variation begins at birth; an infant's microbiota is influenced by factors such as mode of delivery (vaginal birth or cesarean section) and diet (breast milk or formula) and continues to evolve over a lifetime.

The microbiome, on the other hand, refers to the collective genomes of these microorganisms. The entire genetic material of all the microbes - bacteria, fungi, protozoa, and viruses - lives on and inside the human body. The microbiome's genes (collectively called the metagenome) significantly outnumber human genes, with the estimate being that there are at least 100 microbial genes for every human gene. The microbiome doesn't just refer to the microorganisms and their activities and interactions with the host environment. This includes how they metabolize nutrients and drugs, contribute to immune system function, and communicate with the human cellular environment. Thus, Understanding the microbiome means understanding its composition, functions, and interactions with the host organism.


The Intricacies of Microbes

The Complexity and Balance between Different Types of Microbes:

The human microbiome is an incredibly complex system comprised of diverse microbial communities that coexist and interact in various ways. Different microbes, including bacteria, fungi, viruses, and other organisms, each play unique roles and maintain a delicate balance within our bodies. For instance, in the gut, certain bacterial species aid in the digestion of food, the production of vitamins, and the regulation of our immune system. Others are involved in maintaining the integrity of our gut lining, thus preventing harmful substances from leaking into the body.

The balance between different types of microbes is critical to health. According to an article published in the Book " Internal and Emergency Medicine " in 2023, disruption of this balance, also known as dysbiosis, is associated with numerous health conditions, including inflammatory bowel disease, obesity, asthma, and even mental health disorders. This underlines the importance of maintaining a diverse and balanced microbiome.


Challenges and Importance of Researching the Ideal Composition of Microbes:


Studying the microbiome and understanding the ideal composition of microbes is a challenging yet important endeavor. One challenge is the sheer complexity and variability of the microbiome. Each person's microbiome is unique, influenced by genetics, diet, age, lifestyle, and environmental exposures. Defining a "healthy" microbiome that can serve as a benchmark is difficult.

The microbiome is dynamic and changes over time, further complicating the research. The use of antibiotics, changes in diet, stress, and other factors can significantly alter the microbiome composition. These changes can have both short-term and long-term impacts on health.

Despite these challenges, researching the ideal composition of microbes is paramount. A better understanding of the microbiome could pave the way for personalized medicine approaches, where treatments are tailored based on an individual's microbiome. It could also lead to the developing of novel therapeutic strategies for managing various diseases, from metabolic disorders to mental health conditions. The more we learn about the microbiome, the closer we get to unraveling new ways to promote health and prevent disease.

The Role of Birth in Microbiome Development

The Process of Microbial Inoculation during Birth

Microbial inoculation begins at birth, marking the first significant exposure to microbes that will colonize the newborn's body. During a vaginal delivery, the baby passes through the birth canal, exposing it to the mother's vaginal and fecal microbiota. 

This "bacterial baptism" introduces various microorganisms that play a crucial role in seeding the infant's microbiome. These microbes help train the infant's immune system, aid in the digestion of breast milk, and compete with potential pathogenic bacteria.


Microbiomes of Babies Born Vaginally and Via Cesarean Section

The mode of delivery significantly impacts the initial composition of a newborn's microbiome. Infants born vaginally predominantly acquire the mother's vaginal and fecal microbiota, including beneficial bacteria such as Lactobacillus and Bifidobacterium species. These bacteria are particularly suited to digest the complex sugars present in breast milk.

On the other hand, infants delivered via cesarean section (C-section) are not exposed to these maternal microbiota during birth. Instead, their initial microbiota is more similar to the skin microbiota and includes a higher proportion of healthcare-associated microbes such as Staphylococcus. Their microbiome also shows less species diversity compared to vaginally born infants.

The Potential Long-Term Health Consequences of Different Birth Methods

Emerging research suggests that the mode of delivery and its impact on the infant's microbiome may have long-term health consequences. Several studies, including an extensive review published in " The Lancet " , suggest that C-section delivery is associated with an increased risk of immune-related and metabolic disorders such as asthma, allergies, type 1 diabetes, and obesity. The differences in the initial microbiota colonization may partly explain these associations.

However, it's important to note that these are associations, not causations. Many factors, including genetics, diet, antibiotic use, and environmental exposures, also contribute to these health outcomes. Moreover, while the initial microbiota differs based on the mode of delivery, these differences tend to decrease over time, particularly when infants are breastfed. Therefore, while the birth method may influence the initial microbiome and potential health outcomes, it is just one piece of the complex puzzle that shapes an individual's microbiome and health.

The Impact of Regional Species Pool on Microbiome

The Concept of the Regional Species Pool and Its Influence on Our Microbiome:

The regional species pool concept, often discussed in the context of ecology, refers to the collection of microbial species present in a particular environment that could potentially colonize an individual. The same concept can be applied to the human microbiome. Each individual's microbiome is influenced by the regional species pool or the available microbes in their surroundings, including those from the people and environments with whom they interact.

How Our Surroundings, Diet, and Social Interactions Shape Our Microbiomes:

Our microbiome is a dynamic entity, continually changing in response to our surroundings, diet, and social interactions. Our environment exposes us to diverse microbes, which can colonize our bodies and contribute to our microbiome. For instance, individuals living in rural settings tend to have different microbiota than those in urban environments, likely due to various environmental microbial exposures.

Diet plays a significant role as well. Foods we consume not only offer nourishment to us but also to our gut microbiota. For example, a fiber-rich diet promotes the growth of beneficial bacteria that ferment these fibers into short-chain fatty acids, which are important for gut health. Conversely, diets high in processed foods and low in fiber can lead to a less diverse microbiome.

Social interactions, such as those with family members, pets, or peers, also shape our microbiomes. Microbial exchange occurs during these interactions, contributing to the diversity and composition of our microbiomes.

The Differences in Regional Species Pools Across Cultures and Environments:

The composition of the regional species pool, and thus the microbiome, can vary dramatically across different cultures and environments. For instance, studies have shown that individuals living in rural, non-industrialized societies tend to have a more diverse gut microbiome than those in industrialized countries. This difference is likely due to diet, lifestyle, environmental exposures, and lower use of antibiotics and other medications that can affect the microbiome.

Moreover, different dietary habits across cultures can shape distinct microbiomes. For example, populations consuming a Mediterranean diet rich in fruits, vegetables, and whole grains tend to harbor different gut microbes than those consuming a Western diet high in processed foods and animal protein.


The Implications of Microbiome Research

The Link between Depleted Microbiome and Modern Health Issues:

Increasing evidence suggests that a depleted microbiome, characterized by a lack of diversity and imbalance of microbes, may be linked to various modern health issues. This is often referred to as "dysbiosis." It's hypothesized that the Western lifestyle, marked by a diet high in processed foods, sedentary behavior, increased sanitation, and widespread use of antibiotics, may contribute to a less diverse microbiome.

Several studies, including a review in " Genome Medicine," have suggested that reduced microbial diversity may be associated with obesity, type 2 diabetes, and cardiovascular disease. These conditions are more prevalent in industrialized societies and are often related to lifestyle factors. The microbiome can influence metabolic health through various mechanisms, including modulation of inflammation, energy harvest from the diet, and regulation of fat storage.


Discuss the Possible Connection Between Microbiome Health and Gluten Sensitivity, Autoimmune Diseases, and Other Conditions:

The health of our microbiome may also influence gluten sensitivity and autoimmune diseases. In individuals with gluten sensitivity or celiac disease, gluten proteins from wheat and related cereals trigger an adverse immune response. Research has shown that individuals with celiac disease often have a different gut microbiota composition, suggesting a possible role of the microbiome in this condition. However, whether these changes are, a cause or a consequence of the disease is still under investigation.

Autoimmune diseases, where the body's immune system attacks its tissues, may also be linked to the microbiome's health. Conditions like type 1 diabetes, rheumatoid arthritis, and multiple sclerosis have been associated with specific changes in the gut microbiome. It's hypothesized that certain microbes may trigger an inappropriate immune response leading to these conditions. However, further research is needed to fully understand this complex relationship and determine whether manipulating the microbiome could be a potential therapeutic strategy.

Moreover, emerging research suggests a potential role of the microbiome in neurological conditions, often called the "gut-brain axis." Changes in the gut microbiota have been associated with neurodevelopmental disorders, like autism, and neurodegenerative diseases, such as Parkinson's disease. Again, while these associations are intriguing, much more research is needed to elucidate the exact mechanisms and potential therapeutic implications.

While the links between microbiome health and various conditions are becoming increasingly clear, it's important to remember that these are complex conditions influenced by many factors. The microbiome is just one piece of the puzzle. Nonetheless, understanding its role could offer new avenues for prevention and treatment strategies.


The Future of Medicine and Nutrition

Introduce Ombre's Personalized Probiotics and Home Test Kits:

Ombre is a company at the forefront of personalized health, offering solutions to optimize gut health by leveraging the power of the microbiome. Their services include home test kits and customized probiotics. The home test kit allows individuals to sample their gut microbiota in the comfort of their own homes. This sample is then sent back to Ombre's labs for comprehensive analysis.

The other part of their service is personalized probiotics. Based on an individual's gut microbiome analysis from the home test kit, Ombre formulates a unique probiotic supplement tailored to the individual's specific needs. These probiotics help balance the gut microbiota, potentially improving digestive health and overall well-being.

How Microbiome Testing Can Lead to Tailored Health Recommendations:

Microbiome testing provides a snapshot of the types and proportions of bacteria in an individual's gut. Health professionals can provide more precise health and dietary recommendations by understanding the unique composition of an individual's microbiota.

For instance, if certain beneficial bacteria are lacking, a healthcare provider might recommend specific probiotics to help increase their numbers. Or, if an individual's microbiota shows they may have difficulty metabolizing a certain nutrient, dietary adjustments could be advised.

Microbiome testing offers a way to move beyond one-size-fits-all dietary recommendations to a more personalized approach. This personalized, precision nutrition considers an individual's unique genetic makeup, lifestyle, and microbiome to tailor dietary advice. The ultimate goal is to optimize health, prevent disease, and potentially treat existing conditions by modulating the microbiome. However, it's important to note that while this field shows immense promise, it is still emerging, and more research is needed to understand the capabilities and limitations of microbiome-based interventions fully.


Simple Steps to Improve Your Microbiome

Importance of Fiber in Supporting a Healthy Microbiome:

Dietary fiber plays a crucial role in supporting a healthy microbiome. Fiber, found in plant-based foods, is a carbohydrate that human enzymes cannot digest. However, certain types of bacteria in our gut can break down or ferment fiber, producing short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate.

SCFAs have numerous health benefits. They provide energy for the cells lining our colon, support a healthy gut barrier, and have anti-inflammatory effects. They also help regulate appetite and blood sugar levels, reducing the risk of obesity and type 2 diabetes.

Fiber acts as a prebiotic by feeding these beneficial bacteria, promoting a diverse and balanced microbiome. The Clinical Nutritionist has shown that a higher dietary fiber intake is associated with more diverse gut microbiota.


Offer Practical Advice for Incorporating More Fiber into One's Diet:

Incorporating more fiber into your diet doesn't have to be complicated. Here are some practical tips:

  1. Include a variety of fruits and vegetables in your diet: Aim for at least five servings of fruits and vegetables each day. These can be fresh, frozen, or canned (watch out for added sugars or salts).
  2. Choose whole grains: Opt for whole-grain versions of bread, pasta, and rice, which contain more fiber than their refined counterparts. Other fiber-rich grains include oats, barley, and quinoa.
  3. Add legumes to your meals: Beans, lentils, and peas are excellent sources of fiber. Add them to soups, salads, or as a side dish.
  4. Snack on nuts and seeds: Almonds, chia seeds, and flaxseeds are exceptionally high in fiber.
  5. Gradually increase your fiber intake: Increasing your information too quickly can lead to digestive discomfort if you're not used to eating much fiber. Start slow and drink plenty of water to help your body adjust.

Everyone's microbiome is unique, and what works for one person may not work for another. It's always a good idea to consult with a healthcare provider or a registered dietitian before making significant changes to your diet.


Bottom Line

The human microbiome, composed of trillions of microorganisms, plays an essential role in health, with influences starting from birth and extending throughout life. Factors such as birth method, diet, environment, and lifestyle shape our unique microbiome, and disruptions in this microbial balance can contribute to various health conditions, including obesity, diabetes, and autoimmune diseases. 


Innovations like Ombre's microbiome testing and personalized probiotics provide opportunities for tailored health interventions, while the consumption of dietary fiber promotes a healthy and diverse microbiome. Though microbiome research is an emerging field, it holds immense potential for personalizing healthcare, emphasizing the significant impact these tiny microbes have on our overall health.