The human immune system is a marvel of intelligent physiology.  With its complex, interconnected network of specialized leukocytes and proteins, it’s the “Marine strike force” that increases our resistance to microbial and viral diseases and protects our bodies from both internal and environmental pathophysiology.  It is incorrect to assume that the immune system you are born with is the immune system you will have the rest of your life as if genetic controls are entirely responsible for your ability to resist disease.  Aside from some very specific and rare genetic disorders that affect immunity, the structure, function, and coordination of immune cells depend on a healthy diet and lifestyle.  The immune system, like every other organ system of the body, is built by and requires both macro-and micronutrients to function properly.  These proteins, fats, and carbohydrates in the right amounts and balance combined with the full spectrum of vitamins, minerals, enzymes, and trace elements provide the building blocks and fuel for your body to produce healthy immune cells and coordinate their activity.

A healthy immune system depends on systemic and localized inflammatory responses to eliminate the original cause of injury, clear old or damaged tissue, and initiate tissue repair.  Our bodies must be able to effectively toggle between inflammation and anti-inflammation activities to successfully protect us from pathogenic exposure.  The oxidative process created by inflammation which allows immune cells to reach affected tissues must be balanced by anti-oxidants that detoxify or buffer reactive oxygen species (oxidants) and protect cells, lipids, proteins, and DNA from significant damage.  The entire process, from the production of immune cells to their proper function and coordination is greatly impacted by nutrient status and healthy lifestyle choices.  With the mantra, “food first, supplementation second”, I have always maintained that a properly prepared, whole fresh foods, nutrient-dense diet are essential for a regulated and effective immune system response.  All biologic immune components like bone marrow, mucosal cells and secretions, phagocytes, NK cells, granulocytes, cytokines, and nitric oxide depend on micronutrients for their production and function.  These nutrients include, but are not limited to: vitamins A/C/D, amino acids, B12, folate, iron, zinc, essential fatty acids, selenium, B6, copper, and phosphorus.  Anyone concerned about the health of their immune system and its ability to protect them from disease should be asking some important questions-am I eating chemical-free or organic fresh fruits and vegetables rich in nutrients, antioxidants, and gut-healthy fiber?  Am I eating chemical-free, organic, or pasture-raised animal protein that provides the full complement of amino acids and minerals?  Am I engaging in healthy lifestyle choices like exercise, stress management, and getting plenty of sleep? Am I avoiding or limiting tobacco, fast foods/junk foods, refined grains and sugars, environmental chemicals, alcohol, and harmful drugs (prescription or recreational)?  Research has shown us that an altered or insufficient gut biome, insufficient and unbalanced micronutrient intake, obesity and diabetes, uncontrolled systemic inflammation, and high exposure to environmental chemicals can negatively affect the immune system’s ability to respond to pathogens.

Building and maintaining a healthy immune system requires the fundamentals of a healthy diet and lifestyle, especially if you have a pre-existing medical condition and/or have had a recent health crisis.  Aside from this, there are numerous functional foods, botanical preparations, and targeted nutritional supplements that can have a profound effect on the structure and function of our immune system.  The following list highlights some of my favorite immune-supportive nutritional products that I’ve used and recommended.

1. Andrographis-This Ayurvedic “multitasking” plant is probably best known in the West as a botanical that boosts your immune system’s ability to defend you from viruses and bacteria. Andrographis helps you get over colds and flu faster and reduces the intensity of symptoms without causing side effects.
2. Pelargonium– This herb traditionally was used by the Zulu people in South Africa for hundreds of years to treat coughs, colds, upper respiratory tract irritations, tuberculosis, and gastrointestinal complaints. Pelargonium has antibacterial, antiviral, and expectorant properties, which attacks acute infections at their roots, strengthens the immune system and prevents reinfection. Due to its bacteria-killing and immune-modulating characteristics, pelargonium is the perfect choice when treating colds, flu, and other respiratory illnesses.
3. Astragalus-This plant has more than a 1000 year history of use as a medicinal herb and food. Research in animals indicates that it works by stimulating several factors of the immune system. In particular, it appears to stimulate white blood cells to engulf and destroy invading organisms and cellular debris, and it also seems to enhance the production of interferon, a key natural compound produced by the body to fight viruses.
4. Elderberry-This is one of my favorite immune-boosting botanical ingredients. It is one of the best, most clinically studied herbs for fighting colds and the flu. Elderberry disrupts viruses and restores the body’s ability to fight them off without the side effects or drug resistance that you see from prescription medications. And there’s no doubt that elderberry is powerful. It has been found effective against 13 different pathogens, including Streptococcus pyogenes and Escherichia coli. Elderberry extract has been shown to be especially effective when combined with vitamin C  and zinc.
5. Vitamin A-This nutrient is critical to our ability to fight off infections. For example, patients who were treated with vitamin A following surgery saw an increase in lymphocytes – the white blood cells that police our system when we are most vulnerable to infection. Even if you are not deficient in Vitamin A, supplementing with this vitamin provides an immune system boost.
6. Vitamin C-Definitely one of the best-known immune boosters. Taken as a preventative nutrient, it may reduce the incidence of colds by as much as 50 percent! Beyond colds and flu, vitamin C appears to have a natural anti-histamine effect and alleviates allergy and other respiratory symptoms.
7. Vitamin D-Because vit. D is responsible for so many health factors, those deficient in this nutrient are more likely to have colds,  flu, and respiratory ailments. In fact, a long-term British study found that increased vitamin D3 corresponded with a reduced risk of infection.  Individuals with lower vitamin D levels (<30 ng/ml) were more likely to self-report a recent upper respiratory tract infection than those with sufficient levels.

Michael Chase, MS, NTP

Nutrition Science and Dietetics