Also known as: vit D, vitamin D supplementation, 25-hydroxyvitamin D, 25(OH)D
Latest evidence update: 2026-04-01
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Specific salts and chemical forms studied in research. Bioavailability, dose, and clinical use case differ across forms. See each form's page for form-specific evidence.
ProtocolEngine provides general health information based on published research. This is not medical advice. Consult a healthcare professional before starting any supplement or health protocol.
Helps control blood sugar levels and reduce cholesterol in people with diabetes
May reduce disease activity and joint inflammation in rheumatoid arthritis, though evidence is mixed
Associated with better bone health and stronger implant integration in bone
Deficiency is linked to increased risk of dementia and cognitive decline in older adults
Low levels are associated with increased cardiovascular disease risk, particularly in people with diabetes