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Vitamin D and Immune Health: Should You Supplement?

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An estimated 40% of Americans are Vitamin D deficient, which puts them at risk for certain health issues (according to data collected by the National Center for Health Statistics).

Vitamin D is a vital nutrient responsible for many functions.  The body can’t absorb calcium without Vitamin D, so it’s important for bone and teeth health. This nutrient also helps maintain brain and nervous system function, along with playing a role in regulating insulin.

But perhaps Vitamin D’s most crucial function is supporting and enhancing the immune system.  The relationship between Vitamin D and immune health has been well observed in clinical studies.

Unlike other vitamins and minerals, the human body can produce Vitamin D when our skin is exposed to sunlight. We can also receive it in smaller amounts through certain foods and in larger amounts through supplementation.

Sedentary lifestyles spent mostly indoors means less exposure to sunlight, so our bodies naturally produce less Vitamin D. Modern diets also leave a lot to be desired when it comes to nutrition.

Read on to learn more about Vitamin D and immune health, the symptoms of a vitamin D deficiency, and how you can effectively supplement Vitamin D for optimal health.

Symptoms of a Vitamin D Deficiency

If you don’t go into the sun much or live somewhere that makes sun exposure impossible at times, you may be wondering if you have a deficiency. Here are some symptoms to look out for.

  1. Low immune system with frequent illness. If you always catch the office bug, then your immune system could be low because of a Vitamin D deficiency. Along with viral infections, you may also experience more bacterial infections and inflammatory diseases like bronchitis and pneumonia. If you find yourself getting sick once or twice a month, it’s worth investigating whether a Vitamin D deficiency is affecting your immune health.
  2. Fatigue and lack of energy. If you’re experiencing chronic fatigue for seemingly no reason, a Vitamin D deficiency may be the culprit. Vitamin D is crucial to many processes in the body, and a lack of the nutrient can cause overall lethargy and tiredness.
  3. Body soreness, bone pain, joint pain, and lower back pain. Because Vitamin D plays such a large role in bone health, a deficiency can cause bone and joint pain, as well as long-term issues like osteoporosis and inflammation. Patients with a vitamin D deficiency also often report more overall muscle soreness and lower back pain.
  4. Hair loss. A deficiency over a long period of time can cause hair loss and hair thinning. This is because Vitamin D is responsible for supporting the hair growth cycle.
  5. Loss of bone density. Since Vitamin D is necessary for the storage of calcium, long-term deficiency can cause bones to lose their density. This can put you at an increased risk for fractures and bone damage. Older patients are more likely to experience this symptom, though it can occur in anyone who has experienced long-term vitamin D deficiency.
  6. Delayed wound healing. Vitamin D is involved in the production of compounds that are critical to wound healing. If you have a deficiency, wounds may heal more slowly. You may also experience more inflammation and be at greater risk of infection without the immune support of Vitamin D.
  7. Depression. While a direct correlation between Vitamin D and mood disorders like depression hasn’t been identified, many patients with depression also have low levels of Vitamin D. It’s worth considering that a Vitamin D deficiency may play a role in mental health conditions like depression.

How to Diagnose a Vitamin D Deficiency

Symptoms are a good place to start, but it’s crucial to work with a medical provider to diagnose your deficiency before starting Vitamin D supplementation. Like many nutrients, over-supplementation of Vitamin D can lead to toxicity.

So, how do you diagnose a vitamin D deficiency?

First, your provider will discuss your symptoms with you. Then they will likely recommend a blood test to measure your Vitamin D levels. This is the best way to know what’s truly going on in your body.

At Defy Medical, the test we recommend is the Vitamin D 25-Hydroxy Test. This test will measure the amount of Vitamin D and its metabolites in your blood serum to detect low levels.

Everyone is different, which means people may experience deficiency symptoms at different levels, and age also plays a factor. However, there are some general guidelines for a deficiency. According to the National Institutes of Health, Vitamin D ranges are:

  • 12 ng/ml or below – Low
  • 20 ng/ml or above – Satisfactory
  • Above 50 ng/ml – High

The extent to which you are deficient (if you are at all) will determine how your provider treats your Vitamin D insufficiency.

For example, a severe insufficiency may require supplementing high doses of Vitamin D to provide relief. But if you are only a few points short of the “satisfactory” range, you may require a different treatment method to avoid excess Vitamin D.

This is why blood testing and working with a medical provider are important when treating a nutrient deficiency.

Vitamin D3 Supplement Options

If you’re diagnosed with a deficiency, the next step is to begin a supplement regimen.

We highly recommend starting an immediate protocol to address your Vitamin D deficiency so your immune health, bone health, nervous system, and more aren’t negatively impacted.

There are several options available to supplement Vitamin D. This nutrient has two main forms: Vitamin D2 and Vitamin D3. Most supplements are made of Vitamin D3 (cholecalciferol-D3) since there is evidence to suggest it can raise levels more effectively and elevate them consistently.

Since Vitamin D is a fat-soluble nutrient, the body can store it in the fat cells for months at a time. Because of this, it’s possible to supplement with one large dose of Vitamin D once per week or month, or to take a smaller daily supplement depending on your levels and needs.

Keep reading to learn more about your Vitamin D3 supplement options.

Vitamin D3 Injections

If you have a significant deficiency, D3 injections may be the best solution. With injectable nutrition, all of the nutrient is delivered into the bloodstream where it can be absorbed by the body. Comparatively, oral supplements lose a portion of the medication to the digestive process.

We offer Vitamin D3 injections at our Defy Medical clinic in Tampa, FL. You can also order the Vitamin D3 injectable nutrient for self-administration under the careful guidance of your Defy Medical provider, depending on your circumstances. It’s important to be cautious with injectable Vitamin D3 due to the possibility of toxicity at high levels.

You may require injections weekly or monthly to help you maintain optimal levels. Another benefit of D3 injections is that they can raise your levels significantly and last for a long time – sometimes weeks or months depending on your dosage and starting point.

Vitamin D3 Capsules

Vitamin D3 is also available in oral capsules. These come in varying dosage strengths. Vitamin D3 and many other vitamins are measured in international units, or IUs.

Available dosages include:

  • 5,000 IU, typically taken daily
  • 10,000 IU, typically taken daily
  • 25,000 IU, which is a higher dosage and typically taken one to two times per week
  • 50,000 IU, which is a very high dose recommended for significant deficiencies and is typically taken once per week

The dosage you need depends on your vitamin D levels and your response to supplementation. All patients respond differently; your levels may elevate more easily with one high-level dose per month, for example. On the other hand, you may respond better to smaller daily doses.

With oral supplements, capsules are generally better than tablets. This is because tablets require high temperatures to mold their shape, which can degrade the chemical makeup and lessen the benefits.

Capsules typically have a firm outer shell with the supplement suspended inside, either as powder or liquid. Capsule supplements are often more bioavailable, as well, which means they’re more easily used by the body.

Another option is a daily multivitamin that has Vitamin D along with other essential nutrients. This is beneficial if you are deficient in several nutrients along with Vitamin D.

See Vitamin D3 capsule options in the Patient Portal.

Vitamin D3 Sublingual Troches

Sublingual troches are lozenges that can be placed under the tongue, where they absorb into the bloodstream via the tissues there. This type of absorption bypasses the digestive tract, which means more of the medication is delivered to the bloodstream more quickly.

Available strengths include:

  • 2,000 IU
  • 5,000 IU
  • 10,000 IU
  • 25,000 IU
  • 50,000 IU

Similar to other types of supplements, troches can be weekly/monthly in higher doses to maintain levels over time, or more frequently in smaller doses. The dosage depends on the extent of your deficiency.

Troches can be a useful alternative for people who want to avoid injections, who have digestive tract absorption issues, or who prefer a lozenge-style delivery method.

See Vitamin D troches in the patient portal.

Vitamin D Deficiency and COVID-19 Severity: Is There a Correlation?

Because of the relationship between Vitamin D and immune health, the nutrient was identified early on as a potential support supplement in the fight against the coronavirus.

Dr. Anthony Fauci, the director of the U.S. National Institute of Allergy and Infectious Diseases (NIAID) and the chief medical advisor to the president, recommended taking a Vitamin D supplement if you are deficient to lessen your general susceptibility to infection.

Some evidence also indicates that Vitamin D may play a role in protecting people against respiratory infections, specifically.

Additionally, it was observed that patients with more severe cases of COVID-19 often had Vitamin D deficiencies. A recent study also found that the risk of testing positive for COVID-19 was up to 1.77 times greater for participants who were likely to have a deficiency based on levels tested at the beginning of the study.

The gathering evidence has compelled many medical professionals to help patients address potential Vitamin D deficiencies as a proactive strategy. Because treating a deficiency offers other health benefits and Vitamin D supplementation is low risk when taken at the appropriate dosage, it’s considered a worthwhile therapy by many providers.

Other Immune Boosting Supplements

Vitamin D is a great place to start when looking into supplements to support your immune health. Here are some other options to consider.

Vitamin C

Like Vitamin D and immune health, studies have shown that Vitamin C is crucial to the function of the immune system. Since it’s also a very common nutrient deficiency, supplementation is often necessary to make up for what you may not be getting from your diet.

Unfortunately, taking Vitamin C once you’re already sick is unlikely to have an effect. A better approach is regular supplementation that elevates your levels consistently over time.

Options include:

  • A Vitamin C powder that you can add to water or smoothies.
  • A daily multivitamin that includes Vitamin C along with several other key nutrients
  • A high-dose Vitamin C IV infusion that Defy Medical administers at our Tampa clinic. Like high-dose Vitamin D, these IV infusions can elevate levels for longer periods of time. It’s also possible to get the Vitamin C IV infusion and a Vitamin D shot within the same appointment.

Sleep Aids

Sleep is important for a healthy immune system. If you don’t get enough sleep, your body can’t repair itself and replenish its energy levels. Also, studies show that certain immune functions take place during sleep and are cut short when you don’t get enough. All of this leads to being rundown, both in mind and body, which can make you more susceptible to illness.

Here are some options that can help improve sleep and support your circadian rhythm:

  • REM Maintenance Powder, which includes Glycine, Magnesium, Potassium, Inositol, 5-Hydroxytryptophan (5-HTP), and Melatonin. These ingredients work together to relax the body, encourage sleep, improve the amount of deep and REM sleep you get, and more.
  • Glycine sticks, which can be added to drinks as a sweetener or taken by themselves. Glycine supports REM sleep and encourages a healthy circadian rhythm.
  • Melatonin capsules, which can help supplement the hormone responsible for helping our bodies feel sleepy.
  • Melatonin troches, which can be placed under the tongue for quicker and more effective absorption of the sleep hormone Melatonin.

L-Glutathione Injectable Nutrient

L-Glutathione is a potent antioxidant, which means it protects the body from cellular damage and free radicals. It includes the amino acids L-cysteine, L-glutamate, and glycine.

L-Glutathione has shown promise in supporting the immune system, helping with the breakdown of toxins, repairing damaged cells, combating free radicals, and more. L-Glutathione is available as an injectable nutrient which you can administer yourself. Defy Medical also offers the supplies you need for injections, including needles and syringes and sharps disposal containers.

Defy Medical for Nutritional and Immune Support

Defy Medical is a concierge clinic specializing in wellness therapies. We help our patients optimize their health so that they feel better and find more drive to enjoy life. Nutrition is crucial to immune health, energy levels, mood regulation, weight management, fitness gains, and much more. Patients often feel a decline in their overall health, motivation, and drive when these levels are low. Learn more about IV and Injectable nutrition.

In addition to nutritional supplementation for optimal wellness, we offer:

When you become a Defy Medical patient, you access a Care Team with expertise in Men’s Health, Women’s Health, and integrative wellness therapies. You also access convenient telemedicine appointments, an online patient portal for easy ordering of medications, and doorstep delivery of your orders. Our Patient Support team is on-hand via phone, email, and chat as well to answer any questions and help with your treatment plan.