Understanding the best methods of supporting the immune system is an ever-growing priority. With the prevalence of antibiotic use, pathogens are getting stronger and our immune systems less capable of handling the workload.
A healthy immune system is capable of eliminating cancer cells, bacteria, fungi, parasites, and viruses to name a few common threats. The strategies below are designed to help the body maintain a powerful defense system.
How To Improve Your Immune System 101
Day and night, the immune system works tirelessly to keep us protected from dangers, both endogenous (generated inside the body) and exogenous (from outside the body). That much is easy enough to understand.
However, grasping the intricate workings between the multitude of cells and cell-types can be overbearing, so the easiest way to do this is through analogy.
Let’s say you have a high-tech alarm system for your house. The alarm system has two functions, the first is to directly mitigate the threat, and the second is to alert the police. Let’s imagine a virus is playing the role of the robber, and it invades your body.
This triggers the alarm system, and the innate protective measures go into place. Tactic number 1 is to turn up the heat on the home to slow down the invader.
The body produces fever inducing cytokines, interleukin-1 and interleukin-6, which cross over the blood brain barrier to signal the brain’s hypothalamus that the body’s thermal set point needs to be raised.
At this point, your forehead gets hot, your skin blood vessels begin to close, and those all-too-familiar chills set in, all in an effort to keep the virus from replicating. (1).
Tactic number 2 is to increase mucous secretions in an attempt to trap invaders and move them out of the body in a phase known as rhinorrhea.
These are commonly referred to as ‘symptoms’ of a viral infection but are actually part of a well-trained evolutionary defense mechanism.
The best defense, however, is to call the police, and as long as the police force isn’t tied up dealing with a riot somewhere else in the system, the innate immune system has officers on patrol.
These non-specific phagocytic cells (e.g. dendritic, Natural Killer, and macrophages) arrive at a pathogen, engulf, and destroy it.
You can liken these actions to the police surrounding the intruder, capturing, and killing him.
Officers at the scene have tasked duties: calling for backup, directing new officers on the scene, and chasing down suspects.
This is exactly what our innate cells do: attack, direct, recruit, and scavenge.
Innate dendritic cells engulf and partially digest antigens (pathogens like our virus) and present a piece of that antigen on their cell surface, waving it like a flag for other immune cells to see. This activates more innate enforcements but also recruits from a second system of immunity, the adaptive immune system.
Adaptive immunity can be compared to a task-force of detectives that specialize in intrusions – hunting down and tying up perpetrators for the rest of the officers to find. This system is comprised of T cells and B cells.
T cells can be cytotoxic (directly kill infected cells) or helpers (release chemicals called cytokines that recruit other inflammatory mediators). B cells develop into memory cells and antibodies (specialized cells that clone themselves and remember specific antigens).
Antibodies can be likened to specialized agents whose sole purpose is to remember a specific type of perpetrator and be on constant patrol in case of a future invasion.
Antibodies can be likened to specialized agents whose sole purpose is to remember a specific type of perpetrator and be on constant patrol in case of a future invasion.
The immune system is a masterpiece of evolution, an army that has withstood the test of time. But like any army, it is most effective if it has adequate resources and is not fighting wars on multiple fronts. Below are three strategies we can employ to assist our immune system:
Strategy 1: Reduce The Workload
Neutralize Excessive ROS
Free radicals like reactive oxygen and nitrogen species (ROS, RNS) are molecules missing an electron, making them highly unstable and capable of destructive interactions with lipids, DNA, and proteins. (2).
At normal to low levels, ROS and RNS are necessary for the immune system – they are released by innate immune cell macrophages to destroy invading pathogens, and they act as innate system messengers, warning of incoming invaders.
The problem arises when too great a burden of free radicals exists in the body.
ROS interactions with healthy cells create mutations or mark the cell for death. Through a process called lipid peroxidation, one cell after another is affected until the chain reaction can be stopped. (2).
Free radicals are thought to play a large role in the development of many well-known chronic and degenerative diseases like atherosclerosis, cancer, Alzheimer’s Disease, asthma, and autoimmune conditions like rheumatoid arthritis. (2-3).
Progression of these diseases are activated by genetic predisposition and natural accumulation of free radicals triggered by daily routine – psychological stress, excess exercise, pollution, alcohol, heavy metals, radiation (sunlight), and cooking (particularly overheated oils). (2-3).
While some of these are impossible to avoid, there are ways to help your body increase defensive compounds called antioxidants.
Antioxidants donate an electron to stabilize an unstable free radical. They have three main mechanisms of action.
The first is prevention with endogenous antioxidants – superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase work together to stabilize then break down the free radical so it can be used to regenerate glutathione, the body’s most potent antioxidant.
The second mechanism is to scavenge – some of the foods that we eat can act as scavengers for free radicals, seeking them out and neutralizing upon contact. These foods often contain vitamin E and Vitamin C. You can think of their actions like stopping a line of dominoes.
Once you push that first block down, the cascade of falling blocks continues unless one is prevented from reaching the next. Scavengers either prevent the cascade from starting or keep the avalanche of damage from spreading.
The third mechanism is repair – proteolytic enzymes help prevent buildup of oxidized proteins by degrading and removing them from the system. (2-3).
Without antioxidants, free radicals remain unneutralized leaving them to do damage after their intended good. Too many ROS/RNS signals increase the innate response, putting out fires where there are none, leaving less attention for the actual invaders when they do appear – think “boy who cried wolf”. Adding antioxidants to the diet can help improve the body’s response to free radicals and in turn, assist with the immune system.
Too many ROS/RNS signals increase the innate response, putting out fires where there are none, leaving less attention for the actual invaders when they do appear – think “boy who cried wolf”. Adding antioxidants to the diet can help improve the body’s response to free radicals and in turn, assist with the immune system.
Adding antioxidants to the diet can help improve the body’s response to free radicals and in turn, assist with the immune system.
These are just a few of many proven, potent antioxidants that help prevent and stop free radical damage:
● Phytochemical-containing compounds like green tea (epigallocatechin), citrus fruits (triterpenoids), red wine/dark grapes (resveratrol), and chocolate (procyanidin). (4).
● Brightly colored fruits and vegetables like carrots, tomatoes, and peppers; they contain carotenoids and in some cases, lycopene.
● The natural sulfur-packed cruciferous (aka Brassica) vegetables like broccoli, cauliflower, cabbage, kale, etc. will increase levels of glutathione, one of the body’s most powerful natural antioxidants. In addition, consuming enough selenium is necessary for proper glutathione production and use; Brazil nuts are a great source of selenium.
● CoQ10, B-vitamins, iron, and zinc are necessary for mitochondrial energy production in our cells. ROS production is greatly decreased when they have all the necessary nutrients to work properly.
● A note about cooking oils: use saturated fats like butter or coconut oil when cooking with med-high or high heat. Polyunsaturated fats (vegetable oils) are not stable at high temperatures and go rancid (oxidize) very quickly. Oxidized oils, once ingested, act as free radicals and contribute to the onset of many degenerative and chronic diseases.
Attack Invaders Directly
Like a sniper assisting the ground forces of our immune system, antimicrobial agents (no, we’re not talking antibiotics, here) exist in natural, food-based forms. Allicin is a compound in garlic that’s antiviral, antibacterial, antiparasitic, and anti fungal. (5).
Be aware, though, allicin must be exposed, so garlic is best consumed when sliced, crushed, or minced. Another compound, oregano, has both internal and external antimicrobial properties. Ingested oregano oil is antiparasitic and antibacterial. (7).
Oregano essential oil added to hand soap was found to be more effective than regular hand soap, and cleaning solutions with added essential oregano oil enhance the sanitizing actions against pathogenic microbes. (8).
Strategy 2: Build a Stronger Army
The Problem: Gut Dysbiosis
There are two things you have to wrap your mind around in order to understand why gut health is integral to immune health.
- Over 70% of the body’s immune cells are produced in the gut, meaning the majority of our immune system is housed in the gut.
- There are 10 times more microbes (bacteria) in the intestines than there are cells in the body – this essentially means we are more microbe than human! (9).
It is now understood by many doctors and scientists that the microbiome is actually an organ all its own, believing that large changes to its composition may be as damaging as changing the structure of another bodily organ. (10).
Our immune systems begin developing before birth, and exposure to the mother’s microflora helps populate the infant’s gut, serving to activate the immune system and protect from pathogenic bacterial overgrowth. Infant immune system interactions with commensal (friendly) bacteria not only teach these cells friend from foe but also encourage secretions of secretory IgA (sIgA), the antibody found in the protective mucus barrier of the gut lining; decreased sIgA is associated with decreased immune defenses. (11).
Commensal bacteria compete for both space and food in the gut, and when in large enough numbers, they outcompete bad bacteria.
Even adults having been born vaginally and breast-fed (best-case scenario for starting life with a healthy gut population)11 are likely to have an overgrowth of pathogenic bacteria if they’ve ever used antibiotics.
Dysbiosis, the state in which pathogenic bacteria outnumber the commensal bacteria and produce harmful effects, is associated with antibiotic use. (12).
If you’re like the majority of the US population, you’ve been prescribed far more than one round of antibiotics in your lifetime, which means a portion of your commensal bacteria has been wiped clean and replaced by the pathogenic bacteria encountered during everyday life. Dramatic shifts in population result in decreased production of short chain fatty acids (energy produced for colon cells by commensal bacteria), greater risk for intestinal pathogen infection, and increased recovery time.(12).
Even if you haven’t been exposed to courses of antibiotics, stress and diet also play a very large role in microbiome alterations. Stress reduces stomach acid, changes bowel motility, and decreases sIgA concentrations, all of which lead to a detachment of specific microflora, opening a space for pathogens to move in. Diets high in refined carbohydrates and sugars slow bowel motility, increasing the exposure to bowel toxins in your colon.
Too much dietary sugar also increases gallbladder bile release. Pathogenic bacteria or fungi that use bile as a food source are able to increase their “competitive advantage”. This is why high sugar diets support overgrowth of harmful micro-organisms. (12).
Another problem with gut dysbiosis is that it can lead to increased gut permeability which has been colloquially named ‘leaky gut’. Leaky gut refers to when large particles, like gluten or certain bacteria, escape the intestine, venture into areas they don’t belong, and elicit an immune response. If adaptive system antibodies are created against that food or bacteria, then an inflammatory response can potentially be initiated every time one of them is encountered. Not only does this tie up available resources in the immune system, but this chronic inflammation can lead to a host of downstream issues. (13-14).
The Solution: Probiotics
Overall, dysbiosis caused from antibiotics, stress, and diet decrease the immune system’s defenses, leaving you more susceptible to pathogenic invasion. However, lacking adequate commensal bacteria does not necessarily seal your fate; they can be replaced. Probiotics are living microbes recognized by the US Food and Agriculture Organization as well as the World Health Organization as possessing the ability to alter the composition of microflora towards a healthier state. (15).
This healthier state includes protection from pathogens as well as enhanced immunity. Probiotics have been shown to block or modify intestinal cell receptors so that toxins cannot attach, preventing infections. (15).
These commensal microbes upregulate both the adaptive and innate responses to pathogens by increasing sIgA and upregulating phagocytic cell activity, respectively. (15-17).
Finally, as we age, our immune systems naturally become less active. Probiotic supplementation has been shown to strengthen the activity of many cytokines – increasing interleukin (IL) -1β and IL-18 activates IFN-γ production from T, B, and Natural Killer Cells, which enhances phagocytosis (destruction) of pathogens. Enhanced synthesis of TNF-α destroys cancer cells and enables macrophages to better capture pathogens. IL-10 is anti-inflammatory so more of this cytokine helps to put out inflammatory fires. (16-17).
Probiotics, along with controlling stress and a non-refined carbohydrate diet, help push the microflora back into a commensal state, ultimately increasing immune defenses.
Modern “protectors” against bacteria like antibacterial hand soaps, extensive food sterilization techniques, and overuse of antibiotics have left our immune systems out of practice. While we still encounter the most virulent of the pathogenic invasions, the daily fodder for the immune system has been dramatically reduced. Think of your immune system like soldiers on active duty. To perform optimally they need to be kept at the ready, instead of lazily wasting their days because there is no threat.
β-Glucans are the active constituent of certain yeasts, bacteria, seaweeds, and mushrooms and have been known for years as possessing the ability to modulate the immune system. (18).
They work through activating an innate immune response in which macrophages (innate cell) engulf and partially digested the β-Glucans. Since macrophages travel throughout the body and live for a long time, the β-Glucan fragments in the macrophages spread throughout the body and are recognized by other innate immune system cells. (19).
The macrophages release cytokines that can activate more innate immune cells, readying them for attack on viruses or cancer cells, or they can activate the adaptive arm of immunity, priming it for clonal expansion. (20).
Going back to the soldier analogy, you can think of β-Glucans as practice drills, priming and readying each soldier of the immune system for attack. For an under-stimulated immune system, reaction times are going to be slow, leading to a greater risk of infection and slower recovery. Providing a repressed immune system with a primer like β-Glucans helps to decrease those risks.
Strategy 3: Control Inflammation
The adrenal glands are perhaps one of the most important regulatory glands in our bodies, yet they are one of the most overlooked and overworked. The adrenals produce cortisol (aka the stress hormone).
Evolutionarily, cortisol temporarily inhibited the immune system so all bodily energies could be directed towards the fight or flight response. This makes a lot of sense, I mean, who wants to be worrying about sneezing while fleeing from a large animal?!
The problem is, today’s world activates that exact same stress response over things like job, money, diet, and lifestyle – situations that, because they’re not temporary, create a continuous stress response.
Relentless cortisol production suppresses the immune system for an extended period, leaving you open to increased risk of infections, viruses, and colds.
The adrenals were not designed for long-term acute stress so they enter adrenal fatigue where cortisol production is slowed and ultimately lost when the adrenals hit complete exhaustion. In this stage, there is no ability to suppress the immune system.
The infections acquired during adrenal fatigue are now being tended to but without any regulation from cortisol. Lack of regulation leads to increased inflammation, an overly reactive immune system, and increased risk of autoimmune disorders. (18).
To prevent this, we must try to control stress.
Waking in the middle of the night may mean you are having problems regulating blood sugar. The brain survives on glucose so in the middle of the night when blood glucose levels drop, the brain thinks it’s starving and wakes up the adrenal glands.
They produce adrenaline and cortisol to wake the liver, who will push glucose into the blood for the brain to use. The brain is now happy, but it’s also very awake.
If you find yourself in this situation often, try eating a bit of protein just before bed (i.e. ¼ cup of nuts) to help control blood sugar levels. Also, avoid foods that contain refined grains and/or sugars. These foods will spike blood sugar, increase insulin, and elicit an adrenal response.
Physical activity is both a natural stress reliever, raising levels of relaxing endorphins, as well as an immunomodulator. Salivary IgA is the antibody that serves as a primary defense against harmful environmental intruders.
Repetitive high-intensity exercise increases cortisol levels, temporarily suppressing the immune system, lowering the concentration of salivary IgA, increasing the risk of infection. (21)
Whereas moderately intense exercise can elevate the concentration of salivary IgA and reduce influenza symptoms. (22)
Heat shock proteins (HSP) initiate an inflammatory response during times of acute emotional or physical stress, and those who are less physically fit are not as capable of producing HSPs. (9).
The recommendation: exercise when stressed but try to keep it at moderate intensities.
Sleep is a time of recovery and is something most of us can never get enough of. Our hormones and immune systems follow the natural circadian rhythms of the body.
During sleep, cortisol levels are low, allowing for increased activity of pro-inflammatory hormone and cytokine production. Contrarily, wakefulness is associated with increased anti-inflammatory activity. (23).
Cytokines normally active during sleep are active during times of illness, explaining why we get sleepy when we’re sick. In addition, acute sleep deprivation has been associated with decreased antibody production. (24).
Reduce Your Toxic Load
Toxic pollution like heavy metals and persistent organic pollutants (POP) produce free radicals in the body, inciting DNA damage, overactive immune responses, inflammation, and diseases like cancer. (25).
Heavy metal burden is something we all face as our society becomes increasingly industrialized. Unfortunately, the burden has spread to our waterways and their inhabitants, fish.
Methylmercury binds tightly to the tissues in fish, accumulating – the larger the fish, the higher the methylmercury content. (26).
This heavy metal toxin is then passed to whatever eats it, namely, us. Limiting exposure to methylmercury-laden predatory fish like tilefish from the Gulf of Mexico, shark, swordfish, and king mackerel (27) can go a long way in avoiding methylmercury accumulation.
Dioxins are a bioaccumulative POP, meaning they get stored in fat cells, and are associated with reproductive issues, hormone interference, and cancer.
POPs encompass toxins belonging to the “dirty dozen”, a list stating the “dirtiest” or most heavily infiltrated inorganic produce that should be avoided in inorganic forms. (28-30).
Toxic load can be reduced by avoiding animals fed inorganic feed (grass-fed is always preferable), limiting fish and seafood intake (avoid farm-raised Atlantic salmon), and following the Environmental Working Group’s guide for buying organic and inorganic produce according the “Clean Fifteen” and “Dirty Dozen”. (30).
Enhance Digestive Processes
It has been found that those with constipation or blockage issues may have decreased immune function. Colonic hydrotherapy, the process of irrigating the colon, was found to improve immune cell lymphocyte movement from the gut into the systemic (body) circulation, potentially improving immunity. (31).
Proteolytic enzymes help break down proteins into smaller components – foods, bacterial, viral, and yeast cell walls, various other proteins.
Overproduction of transforming growth factor beta (TGF-B) is associated with increased chronic inflammation, autoimmune responses, and increased susception to pathogenic invasion.
One study found that taking a combination of proteolytic enzymes turned down the expression of TGF-B.32 This suggests a role for proteolytic enzymes in decreasing inflammatory response.
Our immune systems have adapted and evolved with us, but sometimes, especially in today’s modern world, the adaptation doesn’t happen fast enough.
We are an industrialized society exposed to pollution, evolving agriculture (GMOs, processed foods, pesticides), and a whole host of immunological insults that over-activate our systems.
However, we are also more “hygienic” than ever before – playing in the dirt less as children, using antibacterial soaps, and cleaning our homes with stronger chemicals. All of this can lead to an underactive immune system. There is a delicate balance of activity and suppression taking place every moment of every day in our immune systems, and utilizing the strategies above allow us to be proactive in maintaining this balance.
There is a delicate balance of activity and suppression taking place every moment of every day in our immune systems, and utilizing the strategies above allow us to be proactive in maintaining this balance.
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