The Virus Series, Part 4: Plant Extracts and Peptides for Optimized Immune Health and Viral Resistance

Herbs Immune Health

In our previous article on viruses and immunity, we discussed vitamins and minerals that enhance immune function. In this article, we discuss plant extracts and peptides that boost the body’s resistance and response to viral infections and increase immune competence.

** Please note: If you want the short summary version of this article with a video, then please click here **

These are potent substances and deciding how much of any given supplement or medication to take is a very individualized decision. It should ideally be done with the guidance of a qualified Functional Medicine practitioner based on individual circumstances and testing.

Plant Extracts

The first category we will discuss is plant extracts and compounds: how they can be utilized for enhancing immune function, how they impact the immune system, and basic dosage ranges. Compounds discussed include echinacea, elderberry, garlic/allicin, quercetin, and shitake mushroom/beta glucan.

Echinacea is a group of herbaceous flowering plants in the daisy family which are found only in eastern and central North America. Though there are ten species of echinacea, only three are used for their medicinal properties: Echinacea angustifolia, Echinacea pallida, and Echinacea purpurea. In studies, “the three herb extracts induced similar, but differential, changes in the percentage of immune cell populations and their biological functions, including increased percentages of CD49+ and CD19+ lymphocytes in spleen and natural killer cell cytotoxicity." (Zhai, 2007). Although different types of echinacea have varied levels of influence on aspects of the immune system, we will focus on the general impact of the herb as all types positively effect both the innate and adaptive branches of immunity (see part 2 of this series for an introduction to the immune system). 

Studies on Echinacea suggest that it:

  • May reduce severity and duration of common cold symptoms (Zhai, 2007).
  • May reduce the chance of catching a cold by 10 – 20% (Karsch-Völk, 2014).
  • Activates macrophages
  • Enhances the immunoglobulin M response (Zhai, 2007). Immunoglobulin M is an initial activity of the adaptive immune system against pathogens.
  • Increases the numbers of circulating leukocytes, including total cell count and subpopulations (i.e., neutrophil, NK cell, and T lymphocyte) (Zhai, 2007).
    NK (natural killer cells) are crucial for fighting viral infections.

Echinacea dosing:

  • For general immune enhancement or when signs of respiratory infection appear, take 300 mg of echinacea three times daily for up to eight weeks.

Elderberry, also known as Sambucus, is a deciduous shrub native to North America and much of Europe and the extracts of flowers and berries are used as medicine. 

Studies on black elderberry extract suggest that it:

Elderberry dosing:

  • 500mg twice daily can be taken as prevention or when symptoms appear. This can be taken the entire flu season as a preventive.

Note that elderberry extract can cause pronounced stimulation of the immune system, so please check with an experienced Functional Medicine practitioner regarding dosing, particularly if you have an autoimmune condition.

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Garlic/Allicin. Garlic (Allium sativum) is a species in the onion genus, Allium and is native to Central China and northeastern Iran. It has been used medicinally for thousands of years in various cultures. 

A potent compound in garlic is allicin. Allicin is an unstable compound, though certain products, such as Allimed, contain stabilized allicin, allowing for an active antimicrobial, immune-boosting agent. 

Benefits of stabilized allicin include:

  • Antiviral activity
  • Increased lymphocyte counts
  • Increased Natural Killer cell counts

Allicin dosing:

  • Medicine with Heart offers high-quality, stabilized allicin supplements. We recommend dosages of 180-450mg of a 100% stabilized allicin extract (not just a garlic extract).

Quercetin is an abundant dietary flavonoid with various medicinal properties, including antiviral and immune supportive activities. Foods high in quercetin include capers, watercress, cilantro, asparagus, and red onions. 

Studies on Quercetin suggest that it:

  • Blocks virus replication in cells through reduced mRNA transcription (Wu, 2015).
  • Inhibits viral entry into cells (Wu, 2015).
  • Acts as a zinc ionophore, transferring zinc across the cell membrane so it can execute its antiviral properties.

Quercetin dosing:

Dosing recommendations for quercetin are 500 mg – 1000 mg per day. 2000mg or more may be used under the guidance of a functional medicine practitioner for histamine intolerance, mast cell activation syndrome (MCAS), or leaky gut.

Shitake Mushroom (Lentinus edodes) / Beta Glucans. Shitake mushroom is an edible, medicinal mushroom native to East Asia and is now cultivated around the world. It has been shown to have various antiviral and immune supportive properties. The primary active component in L. edodes is a (1-6,1-3)-beta-glucan (lentinan) (Gaullier, 2011).

Studies on Shitake/Beta Glucans suggest that they:

Shitake/Beta Glucan dosing:

Fresh shitake mushrooms can be consumed liberally. Beta Glucan dosage ranges from 100 mg – 500 mg. Other mushrooms like reishi, cordyceps, chaga, etc all can have reasonably high beta-glucan content as well.

As with elderberry extract, shitake extract and beta glucans can cause pronounced stimulation of the immune system, so please check with an experienced Functional Medicine practitioner regarding dosing, particularly if you have an autoimmune condition.

Peptides: Thymosin Alpha 1

Peptides are an exciting area of medicine with extensive possibilities to benefit various components of human physiology and we are in the early stages of learning about everything peptides have to offer. 

Peptides are short chains of amino acids (generally between 2 and fifty amino acids long) linked by peptide bonds that bind to and provide instructions to cells. As we are focusing on immune function in this article, we will discuss an immune enhancing peptide: thymosin alpha 1. 

Studies on thymosin alpha 1 suggest it can:

  • Enhance T-cell, dendritic cell and antibody responses and modulate cytokines (Li, 2010) (immune system messengers).
  • Increase efficiency of T-cell maturation (Li, 2010).
  • Stimulate natural killer cells, thereby killing virus infected cells (Li, 2010).

Thymosin alpha 1 dosing:

Thymosin alpha 1 is dosed via subcutaneous injection and should be obtained via a doctor’s prescription. 

There are many natural methods of boosting the immune system and increasing resistance to viruses. These are a few effective, well-researched approaches to supporting your immunity. To implement a highly personalized and target prevention and treatment plan, please work with one of our highly skilled Functional Medicine practitioners.  

In part 5, the final part of our virus/immune series, we will discuss chronic retroviruses and the effect they can have on our health.

As always, please feel free to get in touch with us. If you or someone you know is struggling with viral or immune system issues, contact our clinic today. Book a free 15-min discovery call to see how we can help you with your symptoms. We can answer your questions and help you book an initial consult with one of the functional medicine doctors in our clinic.

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