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PRIME / AM
Vitamin D3
Vitamin D status · Muscle function · Bone + immune health
2,000 IU
Part of PRIME / AM, taken in the morning.
Form, dose and role.
- What it is
- Vitamin D3 (cholecalciferol) is a fat-soluble nutrient involved in a broad set of physiological functions, including normal immune function and bone health.
- Why DEXO chose it
- Vitamin D has a broad physiological role and insufficiency is common. PRIME includes a meaningful daily amount because being consistently sufficient is what the research actually supports.
- Why this form
- Cholecalciferol. D3 is the form most commonly used in human research and is paired here with K2 MK-7.
- Why this dose
- 2,000 IU per day is a widely used maintenance amount that sits comfortably inside commonly cited upper intake guidance for adults.
- Its role in the system
- Vitamin D is included as foundational nutrition rather than as a direct testosterone ingredient. The current randomized meta-analysis found no clear or reproducible effect of vitamin D supplementation on total testosterone or androgen-bioavailability markers.
The human research.
What researchers actually studied. Population. Dose. Duration. Outcome. The details that make a study useful.