How quickly does vitamin d work
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How Quickly Does Vitamin D Work?
Vitamin D Metabolite and Rapid Calcium Transport
Research has shown that certain metabolites of vitamin D can act very quickly in the body. One study found that a specific vitamin D metabolite stimulated intestinal calcium transport within 8-10 hours after oral administration in vitamin D-deficient rats. In contrast, vitamin D itself required a 20-hour lag before showing similar effects 1. This indicates that some forms of vitamin D can begin to work within hours, particularly in enhancing calcium absorption.
Monthly Increase in Vitamin D Levels with Supplementation
A pilot study investigated the rate at which vitamin D levels increase in the blood following supplementation. Healthy volunteers were given 2000 IU/day of vitamin D for one month. The study found that plasma vitamin D levels increased significantly within the first week, with a median increase of 3.09 ng/mL. By the end of the 28-day period, the median increase was 8.85 ng/mL 2. This suggests that noticeable improvements in vitamin D levels can be observed within a week of starting supplementation, with more substantial increases over a month.
Vitamin D Supplementation Guidelines and Effectiveness
Guidelines for vitamin D supplementation vary, but they generally recommend daily doses ranging from 400 to 2000 IU, depending on factors such as age, body weight, and health status. These guidelines aim to achieve optimal serum 25-hydroxyvitamin D concentrations, which are associated with better health outcomes. While natural sources of vitamin D, such as sunlight and diet, can contribute to maintaining adequate levels, supplementation is often necessary to achieve and sustain the recommended concentrations 3. This underscores the importance of consistent supplementation for effective and sustained increases in vitamin D levels.
Conclusion
In summary, vitamin D can start working within hours in certain forms, particularly in enhancing calcium absorption. Noticeable increases in blood vitamin D levels can be observed within a week of starting supplementation, with more significant improvements over a month. Adhering to supplementation guidelines is crucial for achieving and maintaining optimal vitamin D levels, which are associated with various health benefits.
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Most relevant research papers on this topic
Biological activity of a vitamin D metabolite
A vitamin D metabolite, found in rat carcasses, effectively cures rickets, stimulates intestinal calcium transport, and increases serum calcium levels, with a shorter lag time compared to vitamin D.
Highly CitedMonthly Increase in Vitamin D Levels upon Supplementation with 2000 IU/Day in Healthy Volunteers: Result from “Integriamoci”, a Pilot Pharmacokinetic Study
Vitamin D levels can increase rapidly after daily supplementation with 2000 IU/day, reducing deficiency in 62% of healthy volunteers after 28 days.
Non-RCTVitamin D supplementation guidelines
Higher vitamin D levels are associated with improved outcomes for various chronic diseases, and supplementation is recommended based on individual factors like age, body weight, and latitude.
Highly CitedIntestinal absorption of vitamin D: a systematic review
Vitamin D absorption involves passive diffusion and membrane carriers, with some data suggesting that fat consumption with vitamin D improves absorption.
Systematic ReviewHighly CitedMolecular Mechanisms of Vitamin D Action
Vitamin D action in cells depends on sufficient 1,25D ligand, VDR and RXR expression, and cell-specific programming of transcriptional responses to regulate specific genes, potentially delaying chronic aging disorders.
Rigorous JournalHighly CitedPhotosynthesis of previtamin D3 in human skin and the physiologic consequences.
Photosynthesis of previtamin D3 in human skin occurs when exposed to solar ultraviolet radiation, and its slow, steady release into the circulation is a unique mechanism for vitamin D3 synthesis, storage, and release.
Highly CitedBioavailability of vitamin D(2) and D(3) in healthy volunteers, a randomized placebo-controlled trial.
Vitamin D3 increases total 25(OH)D concentration more than vitamin D2, while vitamin D2 supplementation leads to a decrease in 25(OH)D3, explaining the different effect on total 25(OH)D.
RCTRigorous JournalHighly CitedVitamin D in health and disease.
Adequate vitamin D levels are crucial for maintaining health and preventing chronic diseases, with oral dosing being the safest and most economical method.
Highly CitedWhy vitamin D is important and how to access the important resources?
Exposure to sunlight for 15 minutes between 10am-3pm two to three times per week is optimal for synthesis of vitamin D3, which is crucial for maintaining good health.
Systematic ReviewOverview 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.
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