As you think about exploring the world outside of your house again, you probably have questions about how to keep yourself safe.
Strengthening your immune system is one of the best ways to prevent getting sick. An optimized immune system works like a monitoring system keeping watch to protect the body from invaders. The body has different defense systems in place to protect us from harm.
We’ve put this post together to explain a little bit about how the immune system works, things that negatively impact immune system function, and ways to strengthen your immune system for optimal health.
- The Innate Immune System
- The Adaptive Immune System
- Common Causes of a Weakened Immune System
- Supporting your Immune System
The Innate Immune System
The innate immune system is the first line of defense the body uses to protect us from harm inflicted by the outside world. This aspect of the immune system includes:
- Physical barriers like the skin and the hairs in the nose
- Chemical barriers like the acid in the stomach and mucus
- The gut microbiome that competes with pathogens for space in the gut a
The Adaptive Immune System
The adaptive immune system is our body’s immunity that is built over time in response to specific invaders. This is the one that grows stronger with more germ exposure (the reason it’s not really a bad thing if your baby catches a cold). The more germs you are exposed to, the more skilled (or stronger) this system gets. When your body encounters a pathogen, the adaptive immune system creates a memory so that you can quickly defend against that same pathogen when exposed again.
When germs invade the body, they attack and multiply. An optimized immune system is ready to fight and uses several tools to prevent germs and harmful pathogens from causing damage.
If your immune system is compromised or weakened, it won’t be able to fight as well. A weakened immune system leaves your body more susceptible to damage from harmful invaders. When symptoms of an illness appear, it is because an infection has caused damage.
The question now becomes how do we keep our immune system strong and prevent it from becoming compromised? First, we will identify common causes of a weakened immunue system.
Common Causes of a Weakened Immune System
Lifestyle factors that decrease immune system function:
- Less movement
- High stress
- Lack of restorative sleep
- Alcohol exposure
- Less nutrient density
- Not enough protein – an essential component of the immune system – required to produce the antibodies needed to fight the invaders
Medications that decrease immune system function:
Medications can also reduce immune system function. Any of the reasons listed below can be cause for needing to provide your immune system with extra support.
- Commonly prescribed for acid reflux, Proton Pump Inhibitors (PPIs) block stomach acid. This might sound like a good idea if you think your stomach acid levels are too high. However, let’s not forget that stomach acid has several important functions:
- It’s required to aid in the digestion of food (specifically think about protein), and for the absorption of certain nutrients, such as B12, folate, vitamin D, calcium, iron, and zinc. PPIs can actually set you up for several nutrient deficits, all of which can contribute to a weaker immune system.
- Stomach acid also acts as the first line of defense against foodborne pathogens – this means it can help you NOT get food poisoning should you ingest food that hasn’t been properly handled or stored. Food poisoning can also contribute to dysbiosis (later on you’re potentially looking at being set up for chronic digestive issues…hello SIBO) if the balance of good and bad bacteria in the gut is compromised due to that incidence of food poisoning.
- Daily NSAID use can drive damage to the gut lining, also interfering with your body’s ability to absorb nutrients. Damage to the lining of your gut also disrupts the physical barrier that the gut lining provides.
- Corticosteroids suppress the functioning of the immune system.
- Statins that drive cholesterol too low interfere with the immune process.
- Antibiotics reduce the ability of the gut microbiome to work as a barrier and allow pathogens to take residency in the gut.
Supporting your Immune System
Foods that support your immune system
- Bone broth – this is a rich source of glutamine which supports the gut lining. Bone broth also contains N-acetyl cysteine (NAC) which increases white blood cell production and supports healthy lung function.
- Antioxidant-rich foods – aim for five servings of colorful vegetables per day.
- A serving of raw vegetables is one cup and if the vegetables are cooked, a half-cup counts as a serving.
- Produce with the purple pigment can be especially helpful as that pigment is anti-microbial and can reduce the ability of the pathogens to take up residency in the body.
- Cruciferous vegetables like broccoli, kale and cauliflower are full of vitamin C and antioxidants. In a mice study, intake of these compounds were shown to support the immune system when faced with pathogen exposure.
- Turmeric and specifically curcumin, the active compound in turmeric, has been shown to modulate the immune system by controlling inflammation. You can aim for 1-2 tablespoons of turmeric per day, or work your way up to 400mg of a supplement daily for maximum benefit.
- A daily serving of a cultured food or drink each day also supports your immune system by supporting the balance of good bacteria in your gut. Cultured foods and drinks include kimchi, sauerkraut, or other fermented vegetables, kombucha, kefir or yogurt.
- If you’re making a smoothie, be sure to include grass-fed whey protein, this provides immunoglobulins – another immune booster.
Supplements that support your immune system
- Probiotics support both the innate and adaptive immune system by regulating the functions of the immune cells. In other words, probiotics can boost the immune system when we need it to upregulate as well as have an anti-inflammatory effect when we want to down-regulate the immune system.
- High dose vitamin C therapy is being used in some hospitals to improve outcomes in individuals diagnosed with COVID 19 and specifically in those with pneumonia. The biggest limitation with high doses is that loose stools typically occur when taking over 2000mg. We recommend spacing out your intake of vitamin C throughout the day to increase bowel tolerance.
- Zinc, and specifically the oral lozenges, can decrease the severity and duration of symptoms if you do get an infection.
- If you haven’t yet, be sure to read our last post on the research and benefits of vitamin D specific to COVID-19.
Elderberry research update:
While we typically recommend elderberry for immune support because it does have anti-viral effects, it also increases cytokines. Cytokines are inflammatory chemicals released by the immune system to fight off invaders. Normally this is a good thing, we want the body to increase cytokines to protect the body. However, this process is actually problematic with COVID-19 due to its mechanism of attacking the body. COVID-19 works by driving an overactive immune response called a cytokine storm, which can damage the lungs. So while consuming elderberry is not a risk factor for COVID-19, we do NOT recommend using it to prevent this specific virus.
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