The Microbiome in Health and Disease_Final

>> Hi, welcome back. In this lecture, we're going to talk about the microbiome and its role in health and disease because everywhere we look, whether it's in the state of health or disease, the microbiome seems to leave its imprint. It adjusts and adapts to reflect various conditions. So early sign of disease or imbalance can be identified when the bugs in the gut exist in the wrong ratio, creating an altered microbiome or dysbiosis. As a Health Coach, you can't do analysis of the client's gut flora. However, by simply knowing this fact and supporting your clients in balancing their microbiome, you can help your clients start to achieve better health while simultaneously creating a positive force for disease prevention. Microbiome research is in its infancy. It's still unknown if disease is the cause of dysbiosis in the microbiome or vice versa. But the microbiome might serve as a useful tool for therapy or diagnostics in the future. We are at an exciting time filled with potential and discovery, and you're in an amazing position right now to be specializing in this area. As we've mentioned, the gut is filled with bacteria and other types of microbes that can help cause or prevent disease. We place bacteria into two categories. Commensal, which are friendly bacteria, and pathogenic, those bacteria that cause disease. These terms maybe a bit outdated. We realize that pathogenic bacteria like E. coli, the bad guy, we blame for life threatening food poisoning actually has many strains that can exist in small amounts and in the right places and do no harm. However, when E. coli predominates or finds its way into the wrong area or is a strain with a disease causing factor, it can be pathogenic. So these terms relate more to their overall action rather than a specific classification of bacteria. Commensal bacteria are our first line of defense against pathogens. They serve as protection by competing for nutrients and space, and they reduce the pH of the intestine by creating short-chain fatty acids. This creates an unfavorable environment for pathogens. Commensal bacteria also produce toxic metabolites that kill pathogens. Needless to say, we rely a lot on these bacteria. They have our backs, and we need to have their's too. We'll be talking about how to leverage these guys all throughout the course. But what about when bacteria is bad? This warrants discussion too. So let's explore five ways bacteria can cause trouble in the body. One, degradation of the mucus barrier, the front line between you and the world. There are bacteria that live in the lumen, the digestive tube right outside the mucus layer. These bacteria love fiber, plant fiber to be specific, when they don't get enough of it, they start to eat away the mucus layer, an alternate nutrition source for them. As you can imagine, this creates a problem when the first line of defense, the layer that protects your body from potential toxins and pathogens is down. It's as if termites were gnawing away the fence in your yard. Now all sorts of things get through, the good, the bad, and the ugly. If a piece of food like protein gets through without being properly broken down, it can activate the immune system, which is very aware that something is where it isn't supposed to be in a form that the body can't quite handle. Some believe this can lead to allergies as the body then sees that protein forever and perhaps unfairly as a troublemaker. There are two layers of mucosal lining inside the large intestine. The outer layer is where most of our gut bacteria live, then there is the inner mucosal lining which is almost sterile. It makes it tough for nutrients and bacteria to get through. It is in this layer that the oxygen levels rise, which is favorable to pathogenic bacteria. Bacteria can find their way into the mucus layer, either they will have found a new place to make their home or a new place to cause trouble. It really depends on the type of bacteria and their intention. An unwanted pathogen can cause irritation, while a beneficial microbe simply takes up empty space. When commensal bacteria occupy all of the empty spots, pathogens have fewer places to go. Once inside the inner mucosal lining, bacteria both good and bad seem to more directly influence the epithelial layer due to proximity. When pathogens enter the mucosal layer or other areas they are not supposed to be, the body tends to respond with inflammation. Inflammation is talked about a whole lot, but do you know what it actually is? Inflammation is the body's attempt to rid itself of harmful substances by widening the blood vessels so that the white blood cells can enter and ward off bacteria. When microbiome bugs are where they don't belong, inflammation will continue until the source of irritation is gone. Many other factors related to diet and lifestyle can mess with gut permeability, allowing bacteria to be where they shouldn't be. These factors include excessive alcohol consumption and non-steroidal anti-inflammatory drugs, also known as NSAIDs. Okay, so the second way bacteria can cause trouble is through the release of toxins. Bacteria can create all kinds of wonderful nutrients, but when given the wrong food, they can also create molecules that wreak havoc on the gut and release toxins that can overload your system. Up to one-third of the small molecules in the blood come from bacteria in the gut. Sometimes different species can even release the same molecules. Now this is a brilliant evolutionary move so that if one species is knocked out, others can step up and fill in. But when the results aren't beneficial or the bacteria are pathogenic, this isn't such a great thing because now you have multiple species releasing toxins. Diet can create various toxins. For example, it's been shown that eating a diet too high in red meat can create bacterial toxins. Gluten grains can cause bacteria to release zonulin. This opens up tight junctions in cells along the lining of the gut, creating permeability issues. More on that in an upcoming module. Endotoxins are toxins that are released by some bacteria when they die. Lipopolysaccharide or LPS is a combination of sugar and fat molecules that surround bacteria as their protection, like a shield, but it can cause inflammation when it's released into the blood stream, and it's considered a harmful endotoxin. High levels of endotoxins also cause epigenetic or genetic changes, similar to those seen in obesity. They put people at risk for cardiovascular disease, chronic inflammation, diabetes, insulin resistance, stroke, and fatty liver. Number three, gut dysbiosis. To refresh your memory, dysbiosis is an imbalance of bacteria that leads to a disrupted ecosystem or a lack of diversity that can affect resilience. An imbalance in either good or bad bacteria can contribute to disease. Bad bacteria exists all the time in the body, but when they increase, even in slight amounts, they can have a negative effect on the gut and other areas. Have you ever heard of the driver-passenger model? This is the idea that pathogens may spread in response to environmental changes rather than as drivers of colonization. This means when inflammation or other conditions disrupt the microbiome, other pathogens, passenger bacteria can creep in and start to take over because an environment for them to thrive has already been created. According to this theory, the difference between balance or dysbiosis isn't whether the passenger-bacteria is commensal or pathogenic in its nature, but what the condition of the environment is in. Think about when you catch a cold. Typically when your body's environment is strong, when you're well-fed, well-rested, and low on stress, you don't get sick. Now think about how when you're worn out from stress or work or not taking care of yourself, your immune system is down and you catch that bug that's going around. These cold viruses are always present, but the conditions must be right for it to affect you. Now this is something you can address with your clients, are they wearing down their system due to poor food or lifestyle choices? By explaining to them the driver-passenger theory, in simple terms, you can educate them on long-term consequences that might help them make better decisions in the short-term. When gut bacteria are wiped out due to antibiotics or some other environmental factors, there seems to be little that can be done to stop the process, both good and bad bacteria are targeted. Boy, this is where the appendix comes in. This organ has long been thought to do nothing, even Darwin said it was an evolutionary mistake. Until now that is, it turns out that the appendix is actually a holding tank for most of our collection of bacteria and immune cells. You can think of it like a bomb shelter. When you get sick or all the good bacteria are flushed out, the appendix houses more of the good guys who are then ready to flood back in. This is why it's so easily infected or inflamed, resulting an appendicitis because it houses so many immune cells. If you've had your appendix removed, don't worry, it seems this was an evolutionary feature that was most important before the time of sanitation. However, now we're in an age where we have to find a balance between wiping everything out and protecting ourselves from pathogens. The bottom line is that when good bacteria compromises in any way, there are less of them present to compete for nutrients and space, and there are less of them sending signals that wipe out pathogens, leaving the entire burden on your immune system. Number four, chemical signals. Bacteria send chemical signals to the body and to one another. These can influence everyday functions, often in a good way but sometimes in a harmful way. These chemical signals can come in the form of hormones or neurotransmitters. The job of neurotransmitters and hormones are to modulate and regulate responses. They control things like metabolism, fertility, and growth. Bacteria can influence how fast or slow we uptake nutrients, so you can see why it would be important to send the right signals. Bacteria also send signals to the immune system which is why they can influence inflammation. But we'll get into that more later on. Like humans, bacteria are always communicating with each other via these signals. These signals help them coordinate behavior like synchronized swimming. For bacteria, this is all about survival. This communication allows them to protect themselves and share resources, for example, by forming a biofilm. This is a group of cells that stick together and then adhere to a surface. Dental plaque is an example of a biofilm. Sometimes the biofilm can make bacteria resistant to antibiotics. New therapeutics are being researched to see if they can block the communication between bacteria as a new wave of alternative treatment to antibiotics. Number five, bacteria can influence genetic material. Lastly, bacteria can influence DNA and the genetics of humans and microbes by swapping genes or turning them on and off. As far as we know, all types of bacteria use the same basic strategy to survive and colonize. The main goal for bacteria who want to stick around is to be accepted by the immune system and have the ability to utilize resources. If any bacteria or food substance isn't approved, the body's immune system will trigger an inflammatory response to kick it to the curb, which is where you have bacteria influencing genetics. So to recap, the five main ways that bacteria can cause trouble in the body are degradation of the mucous barrier, release of toxins, gut dysbiosis, chemical signals, and the influence of genetic materials. With all that can go wrong, you may be feeling in the dark about all the microbes we can't even see. But we don't want to leave you with all that doom and gloom. So now let's talk about what makes a healthy microbiome. There are three overall key components to remember here. Diversity, richness, and resiliency. Diversity is about having many different varieties of a species of bacteria in your gut. This gives us a variety of workers that can step in to complete any task needed in case any particular species gets wiped out. You can increase your diversity through exposure to new microbes and by feeding your microbiome. This includes being discerning with the use of antibiotics and antibacterials taking probiotics and eating a varied diet. We keep mentioning bacterial diversity in this course because this really is key to gut health. Number two is richness. Richness refers to how many bacteria genes you have, which is the result of how well the bacteria colonize or make a home in your gut. If diversity represents quality, richness represents quantity. Most organisms come into the body with food and pass right through. The ability of a species to colonize depends on its skill in finding and utilizing nutrients and out-competing the existing bacteria in your gut. Fermented foods and fiber are great foods to build a bacterial richness. The more you expose yourself to the bacteria in these foods, the more likely they will be to take up residence in your gut. Diversity and richness lead to resiliency which is number three. Resilience is your microbiome's ability to adapt and recover from any given stress. Resilience can be measured in few ways. First, it's most commonly looked at as the amount of times a community can return to equilibrium following a trauma or the amount of hits a community can take and still recover. Eventually, after enough trauma, you'll pass a threshold and your microbiome can no longer return to the state it was in before. It has adapted. One of the most extreme examples of this is clostridium difficile, an infection that happens in the hospital when patients are given rounds of antibiotics because many of the good bacteria have been wiped out, C. diff is able to run rampant and take over the whole microbiome. We still lack clarity about what defines a healthy microbiome, but to recap, we do know that diversity and richness create resiliency. Again, we face the chicken and egg question. Does a disturbed microbiota reflect unhealthy individuals or does this state cause individuals to become unhealthy? As research continues to unfold, the key is to help you help your clients by exploring ways to increase exposure to good bacteria while at the same time avoiding pathogenic bacteria or triggers. Again, we've mentioned many pathogens live within us peacefully and even provide useful functions. It's only when the balance is disturbed that dysfunction is soon to follow. Regardless, the microbiome provides a mirror for our health. Perhaps a close-up mirror that we may have otherwise overlooked. And even more significantly, it may provide a mirror for the state of our external environment, our microcosm for the macrocosm. As William Blake, the poet said, "To see a world in a grain of sand," perhaps the world can be found in our microbiome. Thank you for tuning into this detailed explanation on the microbiome in disease and in health. This information will help set you up for success as we explore gut disturbances and treatments in this course. Remember, you can always go back and review any material during the course, so don't worry about memorizing all the terms. We also encourage you to post any questions you have in the Facebook group. The education team and your course moderators are here to support you every step of the way. Thank you so much for watching. Bye for now.