Ultraviolet B Radiation: The Vitamin D Connection.
Level 5 - mechanism / opinion, no new human data
Narrative review / book chapter detailing biological mechanisms without systematic search methodology or new empirical data.
PubMed 29124697 · doi:10.1007/978-3-319-56017-5_12
What was done
This chapter provides a narrative review detailing how skin exposure to solar ultraviolet B converts 7-dehydrocholesterol into vitamin D3, the evolutionary significance of this pathway in vertebrates, variables influencing cutaneous synthesis, and guidance on sensible sun exposure.
What was found
The abstract reports purely qualitative overviews of synthesis pathways and biologic functions; no numerical data, sample sizes, or effect estimates are provided.
Why it matters
It outlines the basic physiological mechanisms linking sunlight exposure to vitamin D production and systemic health.
Limits
The abstract provides no primary data, systematic search criteria, or quantitative results. As an expert narrative review, it offers mechanistic background rather than empirical outcome testing.
Cited by
- supports UVB is the specific solar wavelength of energy that triggers vitamin D synthesis in the skin.
- supports UV light from the sun triggers vitamin D production in the human body.
- contradicts Sunlight delivers vitamin D directly into the eyes first thing in the morning to set the circadian rhythm.