Vitamin D Advanced (D2, D3 & D Total)
Understanding Vitamin D Advanced (D2, D3 & D Total)
What is Vitamin D Advanced (D2, D3 & D Total)?
A Vitamin D Advanced (D2, D3 & D Total) is a blood test that measures the levels of various forms of 25-hydroxy Vitamin D (25-OH D2, 25-OH D3 and D total) in the body. This test is a valuable indicator of osteoporosis (bone weakness), rickets (bone malformation), and osteomalacia (bone softening). It can also be used to diagnose/monitor problems with the functioning of the parathyroid gland since the parathyroid hormone (PTH) is essential for vitamin D metabolism.
Vitamin D is a fat-soluble essential nutrient. It exists in two primary forms: Vitamin D3 (Cholecalciferol) derived from animal sources and vitamin D2 (Ergocalciferol) derived from plant sources; both perform similar functions. The main sources of vitamin D3 are certain foods, dietary supplements, and exposure to ultraviolet B (UVB) radiation from sunlight. while vitamin D2 is derived from products or supplements of plant origin and mushrooms etc. Both these forms are converted into 25-hydroxy D2 or D3 respectively in the liver. The levels of 25-hydroxy Vitamin D in blood is considered the best parameter to assess vitamin D status of the body.
As per a study by NCBI (National Center for Biotechnology Information), vitamin D deficiency is highly prevalent across all age groups in India. Low vitamin D levels can lead to many disorders, such as an increased risk of fractures, muscle weakness and lethargy, dysfunction of the immune system, and an increased risk of chronic diseases like diabetes. A Vitamin D Advanced (D2, D3 & D Total) can help determine its deficiency, and sometimes it may also help determine if you have too much vitamin D in your body (most likely from excessive supplements).
The Vitamin D Advanced (D2, D3 & D Total) offers a more detailed assessment of vitamin D status in your body as it evaluates Total 25-OH D as well as 25-OH metabolites of vitamin D2 and vitamin D3 using the highly specialized LC-MS/MS technique. On the other hand a routine Vitamin D (25-OH) test measures only the Total 25-OH D vitamin (i.e D2+D3) and does not differentiate between the two forms. Measuring vitamin D by LC-MS/MS method is considered as the gold standard for vitamin D evaluation because it is a highly specialized and sensitive method that can help differentiate between various forms of vitamin D,25(OH)D and also substrates, D2 and D3. Additionally, LC-MS/MS can detect very small amounts of vitamin D and its byproducts.
Your doctor may suggest the Vitamin D Advanced (D2, D3 & D Total) if you show symptoms suggestive of vitamin D deficiency or excess such as bone deformities, immune system dysfunction, muscle cramps and weakness, dental abnormalities, bone pain, fatigue, loss of appetite, increased thirst, nausea, frequent urination, etc.
No special preparation is required for this test. Consume a regular diet before taking the test. However, it is generally recommended to stop taking vitamin D supplements before this test, as they may affect the accuracy of the test results. Also, let your doctor know about all your other medications, as some can affect the test results.
Lab test result ranges are approximate and may differ slightly between labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. The test results will help them determine your medical condition, make recommendations for lifestyle modifications such as diet and exercise, prescribe medication if required to manage your condition and formulate your overall treatment plan.
What is Vitamin D Advanced (D2, D3 & D Total) used for?
A Vitamin D Advanced (D2, D3 & D Total) can be done:
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To determine deficient, insufficient, or toxic vitamin D levels in the body.
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For routine checkups in individuals with vitamin D deficiency risk factors, including obesity, limited sun exposure, weight loss surgery, digestive disorders like Crohn’s disease, kidney or liver disease, and certain medicines like phenytoin.
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In individuals with vitamin D deficiency symptoms, such as bone deformities, immune system dysfunction, muscle cramps, and dental abnormalities.
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To monitor the adequacy of treatment in individuals who are receiving vitamin D supplements.
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To diagnose/monitor problems with the functioning of the parathyroid gland that affects vitamin D metabolism.
What does Vitamin D Advanced (D2, D3 & D Total) measure?
Contains 3 testsA Vitamin D Advanced (D2, D3 & D Total) measures all forms of 25-hydroxy Vitamin D (25-OH D2, 25-OH D3 and D total).Vitamin D is an essential nutrient that can be synthesized in the body upon healthy exposure to sunlight or absorbed from dietary sources. It majorly exists in the form of vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D2 (ergocalciferol) is largely human-made and can be obtained from plant sources and fortified foods. In contrast, the body produces vitamin D3 (cholecalciferol) when your skin is exposed to sunlight. It can also be absorbed by eating animal-sourced foods.
Both forms of vitamin D (D2 and D3) need to undergo some chemical changes before being available for use in the body. They are absorbed equally well from your small intestine, metabolized in the liver or kidneys, and converted to measurable substances called 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D. Vitamin D Total is the summation of both vitamins.
Vitamin D3
The Vitamin D3 test measures the amount of vitamin D3, also known as cholecalciferol, a type of vitamin D. Vitamin D3 is naturally found in animal-derived products like milk and may be consumed in certain fortified foods or dietary supplements. It is directly synthesized in the skin when exposed to the sun. The Vitamin D3 test determines whether you have enough vitamin D3 in your body to support normal bodily functions.
Know more about Vitamin D3
Vitamin D Total
The Vitamin D Total test measures the levels of vitamin D2 and D3 in your body. This test is an appropriate indicator of the total Vitamin D storage in the body. A vitamin D total test is also recommended in case of abnormal calcium, phosphorus, and parathyroid hormone levels. Individuals with abnormal vitamin D levels become prone to heart diseases, high blood pressure, immune system disorders, different types of cancers (prostate, breast, and colon), and various infectious diseases like influenza, tuberculosis, sepsis, etc. All these reasons make it more important for individuals to check their vitamin D levels.
Know more about Vitamin D Total
Vitamin D2
The Vitamin D2 test measures the amount of vitamin D2, also known as ergocalciferol, which is a type of vitamin D. It is usually found in plant-based sources such as mushrooms and in some fortified foods. The Vitamin D2 test is ordered to determine if a deficiency, insufficiency, or abnormally high level of vitamin D is present in the body, or to monitor ongoing treatment for a previously diagnosed deficiency.
Know more about Vitamin D2
Interpreting Vitamin D Advanced (D2, D3 & D Total) results
Interpretations
Vitamin D level below the normal reference range indicates vitamin D deficiency. This can be because of less sun exposure, dietary lack, or decreased absorption from the intestine.
Vitamin D level above the normal reference range indicates vitamin D intoxication. This is usually due to excess supplementation of the vitamin.
Range:
The normal range of vitamin D Total is measured as nanograms per milliliter (ng/mL) or nmol/L and can vary from lab to lab.
|
Level |
Reference range (ng/mL) |
|
Deficiency |
<20 ng/mL |
|
Insufficiency |
20-30 ng/mL |
|
Sufficiency |
30-100 ng/mL |
|
Toxicity |
>100 ng/mL |
Note:
- The assay measures vitamin D2 (Ergocalciferol) and vitamin D3 (Cholecalciferol) metabolites of vitamin D.
- There can be seasonal variation in 25 (OH) vitamin D levels, with values being 40-50% lower in winter than in summer. It is also influenced by sunlight, latitude, skin pigmentation, sunscreen use, and hepatic function.
- 25 (OH) vitamin D levels can vary with age
- 25 (OH) vitamin D level is increased in pregnancy.
Answers to Patient Concerns & Frequently Asked Questions (FAQs) about Vitamin D Advanced (D2, D3 & D Total)
Frequently Asked Questions about Vitamin D Advanced (D2, D3 & D Total)
Q. What is a Vitamin D Advanced (D2, D3 & D Total), and why is it important?
Q. What are the signs and symptoms of vitamin D deficiency?
Q. What can cause vitamin D deficiency?
Q. Who should get a Vitamin D Advanced (D2, D3 & D Total) done?
Q. How is a Vitamin D Advanced (D2, D3 & D Total) performed?
Q. What is the right time to get a Vitamin D Advanced (D2, D3 & D Total) done?
Q. Are there any risks associated with this test?
Q. What do different vitamin D levels mean in the test results?
Q. What happens if my vitamin D is low?
Q. Can vitamin D deficiency be corrected through diet alone?
Q. How much sun exposure is sufficient to get adequate vitamin D?
Q. How much vitamin D is needed daily?
Q. What other tests can be ordered along with a vitamin D profile?
Q. What are the differences between Vitamin D2 and Vitamin D3?
Q. What is the difference between Vitamin D2, Vitamin D3, and Total Vitamin D?
References
- Garland CF, Garland FC, Gorham ED, et al. The role of vitamin D in cancer prevention. Am J Public Health. 2006 Feb;96(2):252-61.[Accessed 20 Sept. 2023]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1470481/
- Gröber U, Kisters K. Influence of drugs on vitamin D and calcium metabolism. Dermatoendocrinol. 2012 Apr 1;4(2):158-66. [Accessed 20 Sept. 2023]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3427195/
- Religi A, Backes C, Chatelan A, et al. Estimation of exposure durations for vitamin D production and sunburn risk in Switzerland. J Expo Sci Environ Epidemiol. 2019 Oct;29(6):742-752. [Accessed 20 Sept. 2023]. Available from: https://pubmed.ncbi.nlm.nih.gov/30992519/#:~:text=In%20summer%20and%20spring%2C%20with,of%20sun%20exposure%20for%20adults.
- Iraj B, Ebneshahidi A, Askari G. Vitamin d deficiency, prevention and treatment. Int J Prev Med. 2012 Oct;3(10):733-6. [Accessed 20 Sep. 2023]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3483003/
- Kennel KA, Drake MT, Hurley DL. Vitamin D deficiency in adults: when to test and how to treat. Mayo Clin Proc. 2010 Aug;85(8):752-7; quiz 757-8. [Accessed 20 Sep. 2023]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2912737/
- Vitamin D [Internet]. NIH; 12 Aug. 2022 [Accessed 20 Sep. 2023]. Available from: https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
- Aparna P, Muthathal S, Nongkynrih B, Gupta SK. Vitamin D deficiency in India. J Family Med Prim Care. 2018 Mar-Apr;7(2):324-330. [Accessed 20 Sep. 2023]. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6060930/
- Vitamin D [Internet]. Boston, USA: Harvard T.H. Chan; March 2023 [Accessed 20 Sep. 2023]. Available from: https://www.hsph.harvard.edu/nutritionsource/vitamin-d/
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