The body’s immune system is important for helping us to fight off infections, disease and sickness. It is actually made up of 6 different components, according to health coach Ben Greenfield:
- The lymphatic system: A network of organs, nodes, vessels, and tissue that transport lymph fluid throughout the body. Lymph fluid contains infection-fighting white blood cells and the organs and nodes are where toxins, waste, and other unwanted debris are filtered.
- The respiratory system: A series of organs that take in oxygen and expel carbon dioxide. Airways are covered with a mucus layer that traps pathogens and other particles before they can reach the lungs. Tiny hair-like, muscular projections called cilia propel the mucus layer.
- Skin: The skin is the human body’s largest organ that serves as a barrier to the external environment. The skin immune system contains an estimated 20 billion T cells (a type of white blood cell that turns on or off the immune response or attacks and destroys harmful material) that control skin microbes and educates the immune system as a whole.
- Lymphocytes: Small white blood cells (WBCs) that seek and destroy pathogens and orchestrate an immune response. The two types of lymphocytes are B-cells, which make antibodies that attack bacteria and other toxins, and T-cells, which help destroy infected or cancerous cells. Killer T-cells are a subgroup of T-cells that kill cells that are infected with viruses and other pathogens or are otherwise damaged. Helper T-cells help determine which immune responses the body makes to a particular pathogen.
- Spleen: The spleen stores white blood cells and platelets, filters blood and recycles old red blood cells. It also helps fight certain kinds of bacteria.
- Gut: The gut harbors many different bacteria and other organisms that make up what’s called the gut microbiome. Good bacteria help to control harmful colonies of bad bacteria, helps fight pathogens by producing antimicrobial substances, and affect the pH of the gut environment to provide a chemical barrier against harmful microbes. Gut flora also regulates inflammation and activates immune functions.
Within this context, having sufficient levels of vitamin D is critical for a properly functioning immune system.
Why Vitamin D?
Vitamin D has a strong impact on bone density and heart health and it can assist in fighting cancer. Unfortunately, in our modern world, vitamin D deficiency is quite common. In fact, in a 2006 study published in PubMed, it was noted by researchers that approximately 57% of U.S. adults are deficient and 36% of healthy adolescents are deficient.
They go on to note that major advances have been made in vitamin D research that transcend the simple concept that vitamin D is important for the prevention of rickets in children and has little physiologic relevance for adults.
- Inadequate vitamin D prevents children from attaining their genetically programmed peak bone mass, contributes to and exacerbates osteoporosis in adults, and causes the often painful bone disease osteomalacia.
- Adequate vitamin D is important for proper muscle functioning and controversial evidence suggests it may help prevent type 1 diabetes mellitus, hypertension, and many common cancers.
Common reasons for vitamin D deficiency
The most common reasons for vitamin D deficiencies are a lack of sun exposure and poor nutrition.
In terms of sun exposure, most of us have been programmed to think of the sun as “bad” and this simply false. Burning is indeed bad, but exposing one’s skin to the sun for 10-20 minutes a day so as to get a slight bit pink is actually very healthy.
In addition, not eating enough foods like salmon, cod liver oil, egg yolks and organ meats and not eating enough fat is problematic. This is because vitamin D is a fat-soluble vitamin, meaning that it can only be absorbed by the body in the presence of dietary fat.
How vitamin D impacts the immune system
Vitamin D impacts the immune system by turning on important proteins that control anti-microbial processes in the body. These processes allow one’s body to fight off harmful pathogens before they develop into full-blown infections. Since they are dependent on sufficient vitamin D levels, it’s problematic when vitamin D is in a deficient state.
Additionally, vitamin D facilitates the induction of “T cells” which help the body to differentiate between diseased cells and your own healthy cells. In other words, T cells prevent your immune system from attacking your own body, which is the definition of an autoimmune disease. And in fact, vitamin D deficiency is linked to various autoimmune diseases, such as:
- Multiple Sclerosis
- Rheumatoid Arthritis
- Diabetes Mellitus
It’s quite clear that having proper, healthy levels of vitamin D is crucial for a healthy and well-functioning immune system. The only way to know for sure if your vitamin D levels are in the proper range is through a simple blood test.
Unfortunately, most physicians do not include this test in their basic panels, so ask for it. If your doctor won’t include it (which is all too common), order a test yourself. There are several very reputable online testing companies. All it requires is a simple blood draw and then you get the results back within a week or two. Adequate levels should be between 60-90 ng/mL.
Once you have facts, then you can create an action plan, if needed, to get your levels where they need to be and thus, strengthen your immune system to enjoy better overall health.