Armas Laura A G, Dowell Susan, Akhter Mohammed, Duthuluru Sowjanya, Huerter Christopher, Hollis Bruce W, Lund Richard, Heaney Robert P
Creighton University Medical Center, Omaha, Nebraska 68131, USA.
J Am Acad Dermatol. 2007 Oct;57(4):588-93. doi: 10.1016/j.jaad.2007.03.004. Epub 2007 Jul 16.
Ultraviolet (UV)-B light increases vitamin D levels, but the dose response and the effect of skin pigmentation have not been well characterized.
We sought to define the relationship between UVB exposure and 25-hydroxyvitamin D (25-OH-D) concentrations as a function of skin pigmentation.
Seventy two participants with various skin tones had 90% of their skin exposed to UVB light (20-80 mJ/cm2) 3 times a week for 4 weeks. Serum 25-OH-D was measured weekly.
Eighty percent of the variation in treatment response was explained by UVB dose and skin tone. Therapeutically important changes in 25-OH-D were achieved with minimal tanning.
Four weeks was not long enough to reach a steady state at the higher dose rates.
The response of 25-OH-D levels to UVB light is dependent on skin pigmentation and the amount of UVB given, and useful increases in vitamin D status can be achieved by defined UVB doses small enough to produce only minimal tanning.
紫外线B（UV - B）可提高维生素D水平，但剂量反应以及皮肤色素沉着的影响尚未得到充分阐明。
我们试图确定UVB暴露与25 - 羟基维生素D（25 - OH - D）浓度之间的关系，并将其作为皮肤色素沉着的函数。
72名不同肤色的参与者，其90%的皮肤每周接受3次UVB光照（20 - 80 mJ/cm²），持续4周。每周测量血清25 - OH - D。
UVB剂量和肤色解释了80%的治疗反应差异。在最小程度晒黑的情况下，25 - OH - D实现了具有治疗意义的变化。
4周时间对于较高剂量率而言不足以达到稳态。
25 - OH - D水平对UVB光照的反应取决于皮肤色素沉着和UVB给予量，通过确定足够小以至于仅产生最小程度晒黑的UVB剂量，可以实现维生素D状态的有效提升。
