In this article, all about the immune system and the gut microbiome:
I’ve worked as an executive in the health, fitness, and nutrition industry for years. And time and time again, I’ve seen countless people struggle to gain control of long-term health issues that dramatically affect their quality of life.
My little sister, Monica, was one of those people. She was an amazing person. Bright and funny with a big personality that lit up the room when she walked in. Monica struggled with her health, and she was tragically taken from us far too soon.
And that changed my life forever.
Monica inspired me to do everything I can to help others that are at high risk. It is truly devastating to witness the massive, long-lasting impact of the COVID-19 pandemic that we’re enduring, and the countless lives being lost. The fact that this disease is having a significantly disproportionate and severe impact on minority communities, in particular the African American community, is truly heartbreaking for me personally. The most vulnerable of our population are the most threatened.
This current situation has reinforced my desire to help as many people as I possibly can through my work with the science of the gut microbiome.
When I founded Supergut, my goal was to create products that would truly transform people’s health, empowering them to regain control of their lives from conditions that have been controlling them. To create products that my little sister would have benefitted from…
There’s a lot of discussion these days about the elevated risks associated with prevalent ‘underlying conditions’ from this coronavirus pandemic. I know that it’s possible for people to turn their health around if they are equipped with the right knowledge, tools, and desire. And I also know that the gut microbiome is one of the most powerful tools we have at our disposal to do so.
I’ve seen it work.
Emerging scientific research has helped identify actions that we can take, including dietary intervention, to improve the health of our all-important gut microbiomes. (1) And a strong microbiome can help counteract some of the most prevailing underlying health issues that make us more vulnerable to serious infections and diseases.
To drive this point home, did you know that although it’s difficult to quantify exact numbers, experts estimate that between 70-80% of our immune system’s cells reside in the gut? That last sentence is worth repeating:
Literally between 70-80% of your immune cells reside in your gut. (2)
That helps explain why the health of your gut directly impacts your immune system, which controls your body’s natural defense responses and is responsible for reducing your chances of getting infected in the first place.
Yet despite the breakthrough discoveries and emerging gut microbiome research over the past few years, most people aren’t aware of the important role of gut health on immunity. Nor are they familiar with practical, natural, diet-based ways to improve immune health through the gut.
Our Science-Based Approach
I’ve partnered with some of the world’s top experts on the gut microbiome, the immune system, and nutrition to put together this guide for you. I want to provide a helpful, research-based perspective to help cut through some of the noise that’s circulating right now.
This guide includes helpful insights from Dr. Jonathan Jacobs, MD, PhD, a gastroenterologist, scientist, and microbiome expert with a research background in immunology and its connection with the gut microbiome. Dr. Jacobs co-founded the Microbiome Center at UCLA and is one of the leading gut microbiome researchers out there, and he graciously lent his time and expertise in support of our research efforts.
This article also contains contributions from our own resident PhD and nutrition scientist, Dr. Ren-Hau Lai, who has immersed himself in research on gut microbiome health and nutritional interventions, including connections between the gut and immunity.
No hysteria, no hyperbole, just plain and simple science, Supergut-style. We’ve scoured and vetted the science so you don’t have to.
OK, let’s dive in.
Boosting Your Immune System — Just The Facts
There’s so much conflicting information about ‘immunity’ out there these days and how to reduce your risk of contracting a virus or pathogenic bacteria. And it’s often difficult to know exactly whose opinion to trust. The FDA has even been issuing warnings recently to companies that have tried to market miracle cures for COVID-19, so now is the time for extra vigilance.
Since so many of us are currently glued to our phones, checking updates and reading articles, it’s likely you’ve seen recommendations on how to ‘boost your immunity’ to help defend yourself against infections like coronavirus.
And then, you probably read an article or two completely tearing that idea apart, perhaps even saying it’s impossible to ‘boost your immunity’, so you shouldn’t even try.
So, is it even possible? Can you really ‘boost’ your immune system?
In a manner of speaking, yes.
It is really important to keep your immune system strong and prepared to keep you from getting sick. And yes, there are specific actions you can take to strengthen your immunity.
Not surprisingly, “immunity boosting” solutions are not all created equal. Some are more well-studied and substantiated by science than others. So it’s important to do the research to determine the most effective and well-researched approaches, which is exactly what we’ve done for you in this guide.
Which leads to the next question not as many people are asking…SHOULD you boost your immune system?
The answer is a little trickier for this one.
A really important and much less well-understood fact is that just ‘boosting’ your immune system to amplify your immune responses really isn’t enough. You actually need to do more than that to truly get your immune system operating at its best to keep you healthy.
Beyond just boosting your immune system, you also need to keep your immune system well-balanced. What exactly does that mean?
Sometimes you need to amp up your immune responses to be on high alert to protect you and respond to threats. This is especially important when you want to minimize the risk of infection from bacteria or a virus. Other times you actually need to tone down your immune system so your body doesn’t turn on itself and attack the cells and microbes that keep you healthy, which can create excessive immune response, hyperinflammation, and even autoimmune disease. According to Dr. Jacobs, “Other examples of situations where you would want a reduced immune response include rheumatoid arthritis, multiple sclerosis, type-1 diabetes, and asthma and allergies.” Maintaining a healthy state of balance in your immune response is referred to as “immune homeostasis.” (3)
In fact, Dr. Jacobs indicated that, “Most people actually need to focus more on ensuring their immune responses are not overreacting (which can lead to significant issues like autoimmune diseases) vs. focusing entirely on amping up immune response.”
So, yes, you do want to boost your immune system so that it’s strong and ready for a fight if a pathogen should come your way, but you also want to keep it balanced so it knows when and where to not overreact. (4)
Natural Immunity: More Pressing and Urgent Than Ever
The COVID-19 pandemic has put into focus just how important it is to achieve and maintain optimal health before disaster strikes. After all, those of us with pre-existing conditions and diseases are significantly more at risk of developing more severe complications from the disease.
The CDC recently reported about the high correlation between coronavirus hospitalizations and chronic underlying diseases. And tragically the mortality rates from coronavirus infection is also significantly higher for those dealing with serious pre-existing conditions, including cardiovascular disease and diabetes:
This is one of the many reasons it’s personally so important to me to spread the news that creating a healthy, strong immune system is incredibly important and undeniably something that can be within your control (given the time and tools to work on it).
Your immune response is influenced by many factors including:
- Your lifestyle — the specific everyday choices you make (5).
- Your heredity — the genetic characteristics you were born into (6)
- Your environment — the specific environment you live in (again, some have more privilege here, too) (7).
But the bottom line is that ‘immunity’, for the most part, is not a fixed, written-in-stone genetic trait. Your immune system is an incredibly complex system and YOU have the power to influence it naturally without waiting on a vaccine or a drug to treat an infectious disease. YOU can make simple choices that can help turn the tides in your favor.
The Gut Microbiome: Unlocking The Key To Health
To fully understand the immune system and how we can begin to impact it, we need to get familiar with the gut microbiome.
There’s a reason everyone is talking about ‘gut health’ these days.
Let’s start with a basic gut health overview. Your gut microbiome is the group of trillions of tiny organisms (often called microbes) that mostly live inside of your large intestine, and includes bacteria, viruses, and fungi. Your gut microbiome really is an organ in its own right (8). Technological advancements over the past few years have enabled scientists to better understand this incredibly complex collection of microbes in your gut and have brought to light just how significant a role it plays in your overall health.
You can essentially think of your gut as being the control center for your health, as it has been proven to both directly and indirectly impact almost every single system in your body. In fact, most health issues you are dealing with in your life can potentially be traced back to the health of your gut. We’re talking issues like:
- heart health (9)
- blood sugar management (10)
- mental health (11)
- how you digest food and carry weight (12)
- and more
The great news is that you have a large amount of control over the health of your gut microbiome. In particular, you can effectively feed the beneficial bacteria in your gut the right nutrients to help them grow strong and diversify. This can literally transform your health in many positive ways, including…drumroll please: your IMMUNITY (13).
Immunity 101: Intro To The Immune System
So, back to the immune system. How does the immune system actually work?
As part of my aspiration to help as many people as possible strengthen their immunity, I believe it’s important to explain the basics of how your immune system works.
The Inner Workings of the Immune System
Your immune system is an extremely complex network of cells, tissues, and organs that monitors your body for foreign invaders and responds to real (and sometimes even perceived) threats, including pathogenic bacteria and viruses.
Your body is designed to keep pathogens out, and respond quickly when they get in.
In order for a microbe to get into your body and do its damage, first, it has to get past physical barriers, including your skin, the hairs in your nose, small hairs in your respiratory tract, or the surfaces of your organs (like the walls of your intestines). For example, if a pathogen is trying to attack you through your digestive system, it has to survive the harsh environment of the acid in your stomach. You even have immune cells circulating in your body looking for any random foreigners. These are all examples of your body’s inherent and blunt weapons against invaders that comprise your first line of defense, collectively called your ‘innate’ immune system (14).
If the invader makes it past your first line of defense, then you also have a more complex and highly intelligent second line of defense that takes over, called your ‘adaptive’ immune system (14).
Your adaptive system is responsible for more complex and targeted responses to specific threats. These immune fighters learn, memorize, and recognize patterns based on threats they’ve encountered before, and mount a specific response to eliminate the threats.
This adaptive system includes players like B-cells, which are located throughout your body, and are largely responsible for identifying invaders. B-cells also support immune response by producing antibodies, the proteins that attack specific pathogens circulating in your bloodstream and other bodily fluids. Finally, B-cells also record and remember how to deal with them again if they show up in the future.
Other key players in this adaptive system include T-cells. T-cells are like your internal combat troops, which attack invaders that have infected cells that are not directly accessible to antibodies. T-cells are also necessary in most cases for adequate B-cell responses, so they are often regarded as the key orchestrators of adaptive immune responses.
Working Together: The Immune System Team
These collections of cells and microbes work together to defeat pathogenic viruses and harmful bacteria that are ultimately trying to make you sick. Inflammation is typically the first and major immune response to pathogen invasions. Once these cells and microbes have defeated a pathogen, that pathogen gets cataloged, and the next time it tries to enter your body and wreak havoc, your immune system recognizes it and is ready to take care of it more efficiently and effectively.
As mentioned earlier, Dr. Jacobs also notes that, “A well-balanced immune system is also responsible for knowing when to reduce immune responses and reduce inflammation. This can have a significant impact on chronic conditions and diseases including Inflammatory Bowel Disease.”
However, this all leads to some specific problems with the current “novel” coronavirus — it’s a deadly virus that has never been cataloged by anyone’s immune system before. That’s why there is no vaccine yet to “teach” our immune system how to attack this pathogen, and why there are no antiviral drugs yet that have been developed to fight this deadly virus. It’s also why none of us has immunity to it yet (except, theoretically, those who have been infected and recovered). This is a significant and important reason why the coronavirus is so unpredictable and dangerous.
Healthy Gut = Healthy Immune System
So, what does all of this have to do with your gut?
Well, because the majority of your immune cells live in your gut, it makes sense that nurturing your gut and growing a strong, diverse, healthy colony of beneficial bacteria in your gut will improve your immune response. In fact, your gut microbiome plays a critical role in strengthening AND balancing your immune system (13).
Think of your immune cells as the close siblings of the beneficial bacteria that also reside in your gut. The more of these “good guy” bacteria you have at the ready, the faster and easier your immune system can take down a pathogen.
Beyond that, your gut microbiome also communicates directly with your immune system and vice versa. The two work in tandem on your behalf, literally starting from the time you are born. This bi-directional communication between systems is called crosstalk (13, 15).
Your gut communicates with your immune system to help your body learn when to take protective action against pathogens, and it also informs your immune system about which harmless microbes to tolerate and ignore (in other words, when to not attack your own body).
“It is broadly accepted within academia that having certain types of beneficial bacteria in your gut microbiome promotes immune homeostasis,” according to Dr. Jacobs.
The most well-studied and understood way that your gut microbiome influences your immune system is through production of small, but mighty byproducts called Short Chain Fatty Acids (SCFAs) (16, 17). SCFAs are produced when the ‘good guy’ bacteria in your gut consume prebiotic fibers (18). The production of these small molecules has been shown through scientific research to be the primary class of bacterial products that have been studied and shown to be beneficial. (NOTE: It’s possible through continued scientific discovery that other categories of bacterial byproducts will also turn out to be important in this process). SCFAs send signals from your gut to promote health benefits across so many conditions and systems in your body (16, 17, 19, 20). This includes your immune system.
Once SCFAs are produced in your gut, they go on to serve important functions that positively impact your immune system including:
- Strengthening your gut walls to stop infectious bacteria and other pathogens from escaping your large intestine, moving into your bloodstream, and causing infection and chronic inflammation (often referred to as ‘leaky gut’) (21). Most of the specific receptors for SCFAs in your body are in your gut walls. Specific cells in your gut walls actually use SCFAs as a major energy source, literally feeding on these bacterial byproducts.
- Acting as signals to promote and regulate activity of your adaptive immune system, such as stimulating B-cells to produce antibodies, and activating T-cells to help fight infections (including infections in your lungs). Dr. Jacobs described that SCFAs bind to receptors on the walls of these immune cells — and also permeate immune cells — in order to direct their activities (13).
- Traveling to organs throughout your body to help fine-tune your innate immune response system, reducing inflammation in the heart, lungs, and brain (15, 22, 23).
- Generally helping dampen immune system responses when appropriate.
Some other key ways your gut and immune system work together include:
- Your gut has a mutually beneficial relationship with a special class of antibodies called immunoglobulin A (IgA). These IgA antibodies are produced by your B-cells, and help to defeat pathogens (14). IgA also helps keep your gut microbiome diverse, and in turn, the beneficial gut bacteria help produce more IgA (24, 25).
- Your gut helps regulate a specific class of T-cells called TH17 cells. These immune cells live inside your intestine walls and help strengthen immunity and gut health, when well-regulated. Your gut bacteria are also responsible for keeping these guys in check because if they get out of control, an abnormal immune response can result, causing autoimmune issues or lymph node inflammation (13).
And what happens to your immune response if you don’t take care of your gut?
Research has shown that imbalances in your gut microbiome (often referred to as ‘dysbiosis’) weaken your immune system responses (26).
Imagine that a pathogen comes into your body, ready to cause a problem.
If your gut microbiome is not in a healthy and balanced state, the pathogen will likely only meet a few weak and puny soldiers at the gates and will be able to make you sicker, for longer. There are too few beneficial bacteria producing SCFAs to signal your B-cells and T-cells, and your levels of IgA are low. The pathogen is able to do its damage unchecked, and you stay sicker for longer.
Natural Ways to Strengthen Immunity Through Your Gut Microbiome
The amazing thing is that YOU have the power to influence the strength and diversity of your gut microbiome, and therefore keep your immune system operating at its peak to help reduce your risk of infection.
So what are the best ways for you to make use of these new insights around the role of gut health in improving immune health?
One of the most proven and well-studied ways to improve your gut microbiome is to eat plenty of prebiotic fiber (27). Prebiotics are non-digestible food ingredients that promote the growth of beneficial bacteria in your gut. Prebiotic fiber is found in many different plant-based foods and supplements and is literally the fuel for the beneficial ‘good guy’ bacteria in your gut. Some common foods that are rich in prebiotic fiber include garlic, onions, asparagus, oats, and chicory roots (28).
The most impactful prebiotics to improve your gut and immune health are those that produce abundant amounts of SCFAs when consumed by your ‘good guy’ bacteria. At the top of that list is a special type of prebiotic fiber called resistant starch.
It’s called resistant starch because although it is technically a carb, it’s the type that resists digestion by your body in the traditional sense, but is rather digested by the powerful and beneficial good bacteria in your gut (29).
Resistant starch is the preferred food for some of the most beneficial bacteria in your gut and is clinically proven by over 200 studies to produce a wide range of health benefits, largely due to its propensity to produce large quantities of SCFAs when digested (30, 31).
In short, resistant starch is a new superfood that you should get to know because it helps your gut thrive, and in turn your immune system, too.
- Green, completely unripened bananas and plantains
- Potatoes and rice, but ONLY after cooking and cooling them, which changes their chemical structure and increases the amount of resistant starch
- Uncooked rolled oats
- High-amylose cornstarch
- High-amylose potato starch
You can also check out our blog post for more practical ways to start incorporating more resistant starch into your diet, as well as a deep dive into the science of this superpowered starch.
Other Ways to Build a Healthy Gut and Immune System
There are other complementary actions you can take to improve your gut health. Many of which are things you should ideally be doing anyways to improve your overall health and wellness. Research has shown that your gut is connected to most physical and mental bodily functions, so the things you do to improve your overall physical and mental health can also positively impact the strength of your gut microbiome (32, 33, 34, 35, 36), and therefore your immune system. These include:
- Daily movement and regular exercise (32)
- Avoiding highly processed foods with high levels of sugar and net carbs, and low levels of fiber (33)
- Getting plenty of sleep (34)
- Keeping your stress levels under control (35)
- Prioritizing social connections (even if it’s over zoom!) (36)
- Supplementing with high-quality probiotics. But make sure to do your research. Very few probiotic products have much scientific basis proving their efficacy, so it can be challenging finding probiotics that truly colonize in your gut and beneficially impact your microbiome. (37)
- Consider adding some vitamins and minerals which have shown promising benefits on immune system health to your daily regime. Some examples include vitamin C, vitamin D, zinc, and elderberry extract. While more research still needs to be done on the validity and effective doses of these nutrients on immunity, they are worth researching further to decide if supplementation may be beneficial (38, 39, 40, 41).
Impact on Coronavirus and COVID-19
So will taking these steps to strengthen my gut health and immune system prevent me from getting coronavirus and Covid-19?
I need to state this very clearly: As of now, there are no proven, FDA-approved vaccines or treatments that can claim to prevent or cure COVID-19. It’s still the early innings and there remains much to learn about the novel and nasty coronavirus which causes Covid-19.
It doesn’t help matters that there is a ton of misinformation and panic swirling around that makes things complicated to assess. All that said, there are emerging and promising therapeutic applications under development including vaccines and antiviral drugs that will hopefully be introduced over the coming years to help the world limit the future impact of this dreadful and deadly virus.
But here’s what we do know now:
- Emerging clinical case studies indicate that COVID -19 symptoms include gastrointestinal symptoms, which indicates a possible connection between this virus and the gut. (42, 43)
- The American Society for Parenteral and Enteral Nutrition released a recommendation to incorporate prebiotic fiber into the recovery nutrition plan for COVID-19 patients, citing the “benefits to the gut microbiota.”
- Another clinical case study called out prebiotic fiber for its role in rebalancing the gut microbiota in COVID-19 patients in order to reduce the risk of secondary infection caused by gut bacteria seeping out from the large intestine into the rest of the body (44).
- According to Dr. Jacobs, “The microbiome community is a party to the massive coronavirus research efforts underway, including assessment of microbiome profiles of those significantly impacted by coronavirus relative to asymptomatic people. It’s anticipated that different microbiome profiles may indicate different risks of vulnerabilities to major infection from coronavirus.”
While we eagerly await a vaccine and approved treatments for this devastating disease, there are proactive steps you can take RIGHT NOW to improve your immune health, specifically by focusing on your gut microbiome.
There’s no guarantee that you won’t get sick from this virus. The public guidance around physical distancing, wearing masks, and washing your hands frequently are proving to be the most effective ways currently available to protect yourself externally from exposure to the virus.
Being ready and prepared as best you can is in everyone’s best interest to prevent contraction and spread of infections, not just now, but always. This includes fortifying your body’s natural, internal defenses by strengthening and balancing your immune system and keeping your gut microbiome in tip-top shape.
Doing Our Part
I hope this information on the gut microbiome and your immune system is informative and helpful for you. One thing that the world needs a lot more of during these turbulent times is HOPE and I think knowledge and practical solutions can help in that regard.
Here at Supergut, we are excited to announce that our prebiotic resistant starch shakes are now available for free delivery direct to your doorstep! They’re packed with 15g of prebiotic resistant starch fibers and 26 essential vitamins and minerals — including 100% of your recommended daily value of vitamins C and D — and we’ve decided to make them available for free home delivery, direct to your doorstep, no human interaction required.
We are inspired to do our part to help restore hope during these difficult times by helping transform gut health, addressing some of the underlying conditions that affect so many people, and helping people truly fortify and balance their immune systems.