Vitamin D and Immune Function: Why it Matters

The pandemic of Covid-19 has made us all too aware of how important it is to have a strong immune system. It is important to note that no supplement is known to cure or prevent Covid-19 and the most important thing you can do for yourself is to follow the guidelines of the CDC and practice social distancing and proper hygiene. However, having a strong and healthy immune system is always important when it comes to your health, disease resistance and overall well-being. Lifestyle habits such as the foods you eat, your level of exercise, your stress, sleep and even hydration can all help to support a healthy immune system. Let’s talk about Vitamin D and immune function.

A Different Pandemic: Most people are deficient in Vitamin D; an important nutrient that we need for optimal immune function. Vitamin D deficiency is now recognized as a global epidemic and has also been termed “a silent killer” because of how a lack of it can affect immune function and foster inflammation in the body. Some experts even refer to the enormity of Vitamin D deficiency as a pandemic because of the severity of the problem. Over one billion people in the world are deficient in Vitamin D.

Vitamin D and Immune Function

Many people associate Vitamin D with healthy bones and while that is true, Vitamin D also serves many functions to help with immune function and inflammation in the body.

Research shows that being deficient in Vitamin D can increase your susceptibility to infection and to respiratory tract infections. Vitamin D helps to activate and enhance the ‘killer’ T cells and macrophages of the immune system. These ‘killer cells’ detect and fight off fight off pathogens in the body such as bacteria and viruses.

A Vitamin D deficiency can increase your susceptibility to different diseases and infections as well as to immune-related disorders such as asthma, COPD, tuberculosis, a decrease in lung function. Vitamin D is also important in controlling inflammation in the body. It is responsible for regulating the production of immune cells and inflammatory cytokines. The role of controlling inflammation in the body is an important when we look at how inflammation is at the root of many lifestyle diseases such as diabetes, heart disease, high blood pressure, periodontal disease, neurodegenerative diseases, dementia and Alzheimer’s. Low levels of Vitamin D are linked to all these diseases as well as 17 different kinds of cancer. A study published in the Archives of Internal Medicine (June 2008) found that low blood levels of vitamin D doubled the risk of death from any cause in women and men (average age 62).

What is Vitamin D? Vitamin D is classified as a fat-soluble vitamin however it is really a pro-hormone. For the most part, we need to eat different foods to get the vitamins our bodies need to function. Vitamin D is different. We only get about 10% of our Vitamin D from our diet in fortified dairy foods, egg yolks, beef liver and fatty fish. There are two main forms of Vitamin D. Vitamin D3 is found in animal-sourced food and from sun exposure. Vitamin D2 comes primarily from plant sources and fortified foods. When it comes to both forms, our bodies absorb and utilize the Vitamin D3 that we create from the sun or by eating Vit D3 foods much better than when we take in Vitamin D2 from plant foods or fortified foods. Almost 90 % of our Vitamin D intake is from sunlight and from supplementation. It is created and synthesized by our body when our skin is exposed to the sun.

Why is there an Epidemic of Vitamin D Deficiency? The worldwide deficiency is attributed to many factors. Here are some of the reasons that top health experts give:

  • Use of sunscreen: Many of us slather on sunscreen with the intention of protecting ourselves from skin cancer. It is necessary to be proactive with skin cancer prevention, however a sunscreen with an SPF of 30 or more can reduce your body’s ability to create and synthesize Vitamin D by 95%. The skin needs direct bare exposure to be able to synthesize vitamin D.
  • Where you live: The further you live from the equator, the less UVB rays you can get from the sun so those in Northern countries have a difficult time getting enough sun.
  • Where you work: Modern mankind tends to work indoors during daylight hours, and this can impede sun exposure. The windows in our homes, offices and cars are now manufactured with UV blocks.
  • Age: Older people are at risk because aging skin is less proficient in absorbing the sun’s rays and synthesizing Vitamin D. Infants are even at risk if they are solely breast fed.
  • Air Pollution: High pollution in our cities can block the sun’s rays
  • Levels of Melanin in your skin: All people have the same number of melanocytes, but some people make more melanin than others. If your cells make small amounts of melanin, your hair, skin and eyes will be very light. If your cells make more melanin, your hair, skin, and eyes will all be darker People with darker skin colors also run a high risk of deficiency because of the melanin in their skin blocks the rays of the sun from being absorbed and converted to Vitamin D in the body.
  • Other Factors: People who are homebound or cover their bodies and heads for religious reasons are at risk.

How to get more Vitamin D

1. Sun Exposure: Avoiding the sun can be a double-edge sword. Slathering on excessive sunscreen can help prevent skin cancers, but it also makes it almost impossible for us to get the Vitamin D that we need to be healthy and resist infections and disease. Do you ever feel yourself drawn to the sun and experience a feeling of bliss when the sunlight hits you after a long cold winter? Craving the sun is a survival-based mechanism in our body because of our dire need of Vitamin D. The sun is foremost your best way of getting enough Vitamin D; midday sun is best. Getting anywhere from 15 -30 minutes without sunscreen is enough to produce the Vitamin D that you need. Make sure that you expose large areas of your skin to maximize exposure. If you have dark skin or are over 65 years old, you will have a compromised ability to absorb and synthesize Vitamin D from sunlight exposure. Unfortunately, we don’t store up the Vitamin D we get from the sun. It needs to be reinforced daily. That’s why it’s important to try to get outside every day.

2. Food Sources of Vitamin D3 (Best form to utilize)

  • Salmon, Herring, Sardines, Canned Tuna, Oysters and Shrimp as well as Cod Liver Oil
  • Liver
  • Egg yolks
  • Butter

Sources of Vitamin D2 (Not as effective as sources with D3)

  • Mushrooms (grown in UV light)
  • Fortified foods- most milks, soymilk, nut milks, dairy products, orange juice and cereals are now fortified with Vitamin D2

3. Supplements: Since getting enough sunshine year-round while protecting our skin from cancer produces a quandary for most of us; supplementing is probably your best insurance against being deficient. Nearly everyone from infants to adults and seniors needs to supplement with Vitamin D3. Vitamin D3 is inexpensive and easy to find. It is important that you check with your doctor or healthcare provider before supplementing and find out the best amount for you to take based on your blood levels and your individual health concerns and medications.

Try to get out in the sun during your lunch breaks sans the sunscreen and eat fatty fish 2 -3 times per week as well. Talk to your doctor about supplementing and to see if you are at risk for deficiency. Improving your Vitamin D levels will support your immune system and help you to better ward off infections. Your mood, focus and outlook on life can improve when your blood levels are optimized and you help protect yourself from osteoporosis, cancers, diabetes, heart disease, autoimmune problems, gum disease and degenerative brain disorders and a host of degenerative disease conditions. Every cell in your body needs Vitamin D3 every single day to help you stay healthy and strong.

By: Cindy Luisi WHE, WHC, CCP, CDL Wellness Coach


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