Vitamin D3
Cholecalciferol (D3)
THE SUNSHINE VITAMIN FOR BONES, IMMUNITY & MOOD
Vitamin D3 (cholecalciferol) at 5,000 IU — the form your skin produces naturally from sunlight. It supports calcium absorption, bone density, immune function, muscle strength, mood regulation, and hundreds of gene expressions throughout the body.
30-day supply
Key Benefits
Supports calcium absorption and bone building
Promotes muscle strength and function
Supports immune health and cell-to-cell communication
Supports mood regulation and cognitive function
Supports These Goals
Linked Biomarkers
Our blood test can measure these markers to personalize your dose
Why you'll love it
Vitamin D is less of a vitamin and more of a hormone — and it influences the expression of over 1,000 genes in your body. Despite its critical importance, an estimated 42% of American adults are deficient, with rates even higher in people with darker skin tones, those who live in northern latitudes, and anyone who spends most of their time indoors.
The consequences of deficiency are far-reaching. Beyond its well-known role in calcium absorption and bone health, vitamin D is a key regulator of immune function. It activates your innate immune system's first responders (including antimicrobial peptides like cathelicidin) and helps modulate the adaptive immune response to prevent overreaction. Low vitamin D is consistently associated with increased susceptibility to respiratory infections.
Vitamin D also supports muscle strength (deficiency is linked to increased fall risk in older adults), mood regulation (low levels correlate with seasonal depression), and cardiovascular health. We use D3 (cholecalciferol), the same form your skin produces from sunlight, at 5,000 IU — a dose supported by research for achieving and maintaining optimal blood levels of 40-60 ng/mL.
Clinical Evidence
Our recommendations are grounded in published clinical research. Here are key studies supporting the benefits of Vitamin D3.
Vitamin D supplementation reduced cancer death risk by 13%
Association between vitamin D supplementation and mortality: systematic review and meta-analysis
2019
Vitamin D supplements reduce symptoms of depression
The effect of vitamin D supplementation on depression: a systematic review and dose-response meta-analysis
2024
Study titles shown are simplified summaries of the original research for readability. Original titles are shown in italics below each heading. All studies cited are from peer-reviewed journals indexed in PubMed. Links open in a new tab to the original source. These studies are provided for informational purposes and do not constitute medical advice.
How much do I really need?
Take one capsule daily with a fat-containing meal. Vitamin D is fat-soluble and requires dietary fat for absorption. For those with known deficiency, a healthcare provider may recommend higher doses initially. Getting your blood levels tested (25-hydroxyvitamin D) helps determine the right dose for you.
Safety & Transparency
Full transparency — here's exactly what's in every capsule, verified by our manufacturer.
Third-Party Tested
Every batch is independently tested by ISO-17025 accredited labs for purity, potency, and contaminants.
Doctor Formulated
Designed by healthcare professionals using evidence-based research and clinical expertise.
cGMP Certified
Manufactured in cGMP & UL certified, FDA-registered facilities with a flawless inspection record.
Important Information
Contraindications:
- •hypercalcemia
- •sarcoidosis
Those with hypercalcemia, sarcoidosis, or granulomatous diseases should consult their healthcare provider before use. Have your vitamin D levels monitored if supplementing long-term at 5,000 IU.
As with any natural health product, you should consult your healthcare practitioner on the use of this product. Store product in a cool and dry place. Keep out of reach of children. If you experience an adverse event or allergic reaction, discontinue use immediately and contact a healthcare professional.
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