What is the difference between vitamin d and vitamin d3
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Differences Between Vitamin D and Vitamin D3
Introduction to Vitamin D and Vitamin D3
Vitamin D is a crucial nutrient for maintaining bone health and calcium homeostasis. It exists in two primary forms: Vitamin D2 (ergocalciferol) and Vitamin D3 (cholecalciferol). Both forms are used to fortify foods and in dietary supplements, but they have different origins and potencies.
Sources and Production
Vitamin D2
Vitamin D2 is derived from plant sources and fungi. It is produced by the ultraviolet irradiation of ergosterol, a compound found in fungi and yeast6.
Vitamin D3
Vitamin D3 is synthesized in the skin of humans and animals when exposed to ultraviolet B (UVB) rays from sunlight. It is also found in animal-based foods such as fatty fish and liver5 7.
Potency and Efficacy
Comparative Potency
Research indicates that Vitamin D3 is significantly more potent than Vitamin D2 in raising and maintaining serum 25-hydroxyvitamin D [25(OH)D] levels. A study showed that Vitamin D3 is approximately 87% more effective than Vitamin D2 in increasing serum 25(OH)D concentrations1. Another meta-analysis confirmed that Vitamin D3 is more efficacious at raising serum 25(OH)D levels compared to Vitamin D2, especially when administered as a bolus dose2.
Storage in the Body
Vitamin D3 also results in greater storage of vitamin D in the body compared to Vitamin D2. In a controlled trial, the subcutaneous fat content of Vitamin D3 increased significantly more than that of Vitamin D2, indicating better storage and utilization1.
Physiological Effects
Bone Health and Calcium Absorption
Both forms of vitamin D are crucial for calcium absorption and bone health. However, Vitamin D3 is more effective in maintaining adequate levels of 25(OH)D, which is essential for these physiological processes5.
Immune System
Vitamin D3 has been shown to have a more pronounced effect on the immune system compared to Vitamin D2. It influences gene expression related to the innate and adaptive immune systems, potentially shifting the immune response to a more tolerogenic status. This effect is less pronounced with Vitamin D26.
Conclusion
In summary, while both Vitamin D2 and Vitamin D3 are important for health, Vitamin D3 is more potent and effective in raising and maintaining serum 25(OH)D levels. It also has a greater impact on the immune system and is better stored in the body. Given these advantages, Vitamin D3 is often the preferred choice for supplementation to correct vitamin D deficiency.
Sources and full results
Most relevant research papers on this topic
Vitamin D(3) is more potent than vitamin D(2) in humans.
D3 is 87% more potent in raising and maintaining serum 25(OH)D concentrations and produces 2- to 3-fold greater storage of vitamin D than equimolar D2, making it the preferred treatment option for vitamin D deficiency.
RCT
Very Rigorous Journal
Highly CitedComparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis
Vitamin D3 supplementation is more effective at raising serum 25-hydroxyvitamin D concentrations than vitamin D2, potentially making it the preferred choice for supplementation.
Meta-AnalysisVery Rigorous JournalHighly CitedVitamin D2 vs. vitamin D3: They are not one and the same
Vitamin D3 is more than twice as effective as vitamin D2 at raising vitamin D levels, when given at a low dose in a physiologically relevant and public health-friendly manner.
Meta-AnalysisVitamin D2 vs. vitamin D3: Are they one and the same?
Vitamin D2 and D3 may have distinct and significant differences in efficacy, potentially impacting vitamin D status and calcium absorption.
Overview of general physiologic features and functions of vitamin D.
Vitamin D3 plays a crucial role in calcium absorption, phosphate absorption, bone mobilization, and kidney reabsorption, with new selective analogs for therapy emerging.
Highly CitedVitamins D2 and D3 Have Overlapping But Different Effects on the Human Immune System Revealed Through Analysis of the Blood Transcriptome
Vitamin D3 supplementation may shift the immune system to a more tolerogenic status, while vitamin D2 supplementation may have a stimulatory effect on type I and type II interferon activity.
Non-RCTThe serum vitamin D metabolome: What we know and what is still to discover
Advances in LC/MS/MS technology have enabled the detection of new vitamin D metabolites in human serum, potentially impacting our understanding of vitamin D metabolism and its role in human health.
Highly CitedMolecular evaluation of vitamin D responsiveness of healthy young adults
Vitamin D responsiveness classification in healthy young adults can provide additional information beyond single 25(OH)D3 serum measurements.
RCTVitamin D and Its Synthetic Analogs
Vitamin D3 supplementation is essential for bone health and autoimmune diseases, and its synthetic analogs offer potential for treating various cancers.
Highly Cited