Vitamin D
VitaminsKey Benefits
How It Works
Vitamin D acts as a hormone precursor. Once converted to its active form (calcitriol) in the kidneys, it binds to vitamin D receptors found in nearly every cell, regulating over 1,000 genes involved in calcium metabolism, immune function, and cell growth.
Dosage & Timing
Recommended Dosage
1,000-5,000 IU daily (up to 10,000 IU under supervision)
Best Time to Take
Morning with a fat-containing meal for absorption
Recommended Form
D3 (cholecalciferol) preferred over D2
Side Effects
Generally safe at recommended doses. Excessive intake can cause hypercalcemia, nausea, and kidney issues.
Drug Interactions
May interact with steroids, weight-loss drugs, and cholesterol-lowering medications. Enhances calcium absorption.
What Does The Research Say?
Extensive research supports supplementation for deficiency. Meta-analyses show benefits for bone health, immune function, and reduced all-cause mortality. The VITAL trial showed modest benefits for cancer prevention.
Where to Buy
Buy Vitamin D on Amazon
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Try Huel →This information is for educational purposes only and does not constitute medical advice. Researched by the editorial team at NexoraOS, supplement user since 2018. Always consult a qualified healthcare professional before starting any supplement. Individual results may vary. Amazon links are affiliate links.