UNDERSTANDING THE GUT MICROBIOME
Your Microbiome is a Partner in your Health
The large intestine, or gut, obviously plays an important role in digestion, but it does much more than that. It’s also home to your personal microbiome, the bacteria which live inside you, and your microbiome’s health is directly tied to your health.
Scientists now link the increasing prevalence of many chronic diseases today (such as obesity, type 2 diabetes, prediabetes, constipation, and many autoimmune issues) to the loss of healthy activity in the gut microbiome.
The good news is, we can do something about it; your microbiome is more about diet than genetics. Twins raised separately will have totally different microbiomes, depending on what they eat! Your microbiome is uniquely yours and you can change it, rebuilding it by learning what it needs – and therefore what you need.
The Numbers Matter: We Are More Bacteria than Human
The gut contains an entire, hidden world inside your body – tens of trillions of bacteria and other tiny microbes live there. There are a thousand different kinds of bacteria in you, and they weigh roughly two to four pounds in the average adult, about the size of the human brain. You contain ten times more bacteria cells than you do human cells. That’s a lot to imagine.
Humanity evolved with this incredible living system inside each one of us. Think of it as a lush garden with a vast variety of life, one that requires plenty of rain, sun, and good soil to keep everything growing happily.
If you’re not familiar with the details, your microbiome:
-is mostly found in the large intestine of the gastrointestinal tract,
-contains about 50 trillion microorganisms,
-consists of around 1,000 different types of bacteria (diversity is important),
-weighs on average 2-4 pounds (about the size of the average human brain),
-means you are made up of more non-human cells than human cells,
-has an ecosystem of its own and is dependent on a food supply and a protected environment,
-is dependent on what we eat,
-creates signals communicating with our brain,
-is closely associated with health, and
-can become disrupted.
As these points show that it is a good idea to get to know your microbiome a little better.
A Happy Gut Shakes Hands with the Brain
The microorganisms in your gut (also known as your microbiota) digest food that our bodies can’t break down. They are therefore dependent on the foods we eat, and they need a special kind of nutrient. Those nutrients are called prebiotics. Not only do your native microorganisms need prebiotics to survive, they need prebiotics in order to work with us and for us. Our bodies just don’t function well if our microbes are not alive and thriving.
Well-fed microbiota produce molecules that trigger the release of signals. Those signals then travel from the gut to other parts of the body, like the brain. This connection is known as the gut-brain axis, and your gut microbiota is sometimes referred to as your second brain.
The signals let your brain know when you’ve had enough to eat and you’re satisfied, for example. If there aren’t enough of the right kind of bacteria, and the right kind of food for those bacteria, the signals are weaker.
Only certain types of food lead to the creation of these signals. Just eating simple carbs all day won’t feed the bacteria and won’t lead to a sense of satisfaction. That’s because weak signals make it easier for you to ignore or even override the message and continue eating, even after you’ve already had enough.
The Gut: Where Your Insides Meet the Outside
Your gut is crucial for another reason ‒ it accounts for about 70 percent of your immune system’s interaction with the outside world. The inner lining of the large intestine is coated with a thick layer of mucus. This mucosal barrier, as it is known, is a first line of defense that keeps potentially harmful bacteria or other material from getting into your bloodstream. Some of your good gut bacteria live in the mucus layer, keeping it thick and intact for when a threat is detected.
A few years ago, the Sonnenburg lab at Stanford discovered that something very odd occurs when there are no prebiotics for those microbes to eat – they start eating mucus instead. “This is the stage where you say, ‘Oh my God. They’re eating me,’” Sonnenburg said. “You can see it.” The mucosal barrier gets thinner, and that can lead to inflammation and a leaky gut.
Diet Alone Can Change Your Microbiota and Lead to Health or Illness: You Decide
All of these things explain why your diet is so important: your choice of food will determine whether your microbiome gets enough prebiotics. Remember, your microbiome is like a lush garden. Without the right care, a garden will die off and some inhabitants might be lost forever. This happens in your microbiome too. Without nutrients, your microbes die off; harmful bacteria may then flourish, and the healthy ones may produce the wrong signals, or be missing altogether.
Other factors also contribute to the loss of our microbiome, from an overuse of antibiotics to an overly sanitized world. Another major cause for concern is the abundance of food additives we consume. There are over 3,000 food additives, mostly chemicals, added to processed foods today:
-Preservatives (ascorbic acid and benzoate).
-Sweeteners (high fructose corn syrup, sucrose, aspartame).
-Dyes (FD&C Green No. 3, caramel color, Citrus Red No. 2).
-Flavorings (artificial flavors added).
-Flavor enhancers (monosodium glutamate [MSG], disodium guanylate).
-Fat additives (olestra, modified food starch).
-Emulsifiers (Soy lecithin, Polyglycerol Ester), etc.
Some of these chemicals can cause chaos in your gut microbiome.
Scientists who study and compare the gut microbiome of people in different societies around the world find that the American gut, on average, is not the same as in healthy people. Even in healthy people today, the microbiome is not as diverse as our ancestors’ microbiomes. Our ancestors ate a lot more fiber than we do – a whole lot more! Prebiotic fiber was naturally a larger part of diets before the industrialization of our food crops, and fiber is a main source of those prebiotics we need to feed our microbiome.
Food preferences determine the kind and amount of nutrients that are available to feed the microbiota. If one kind of bacteria doesn’t have the right nutrients, the gut environment ‒ the microbiome ‒ changes. Remove the fiber in your diet and the natural diversity and total numbers of microbes will shrink.
Maybe It’s Not the Bad Things We Eat, but a Lack of the Good Things, That Leads to an Unhealthy Microbiome.
Moises Velasquez-Manoff, in ‘How the Western Diet Has Derailed Our Evolution‘, writes about the research of husband and wife microbiologist team, Justin and Erica Sonnenburg.
“… by failing to adequately nourish key microbes, the Western diet may be starving them out of existence. They call this idea ‘starving the microbial self.’ They suspect that these diet-driven extinctions may have fueled, at least in part, the recent rise of non-communicable diseases.”
So, burgers and fries have nearly killed our ancestral microbiome and are causing diseases? Maybe: but just as importantly, by filling up on fast foods you are less likely to eat the yummy pile of broccoli, asparagus, and onions your gut needs.
(To take a deeper dive into the world of lifestyle, diet, fiber, and the microbiome, you can find Erica Sonnenburg, PhD’s two-part presentation on the topic here.)
How to Get the American Gut to a Blissful Gut
The simple answer is to simply eat more fiber! And if that seems too tough to do on a daily basis, try BiomeBliss. BiomeBliss is designed to supply you with the specific nutrients that help keep your gut healthy. As a plant-based prebiotic, BiomeBliss provides three key nutrients:
-Inulin from agave provides nutrients that feed the microbes.
-Polyphenol antioxidants from blueberries encourage certain bacteria associated with a healthy microbiome.
-Beta glucan from oats protects the gut lining and supports your immune system.
You may not always make the healthiest food choices, but don’t punish yourself too much for it. Just make sure to catch up on the good stuff you may be missing with a delicious drink designed to satisfy your microbes – it’s an easy way to get on their good side.
A Microbiome Glossary:
Microbiota: The collection of microbial communities, such as bacteria, archaea, fungi and protists.
Microbiome: This term was initially used to refer to the genes of microbes; it is also commonly used to refer to the microorganisms themselves (i.e., the microbiota).
Probiotics: These are live microorganisms that, when taken in adequate amounts, confer a health benefit.
Prebiotics: These are nutrients that are selectively utilized by microbiota to produce health benefits.