Vitamin D production depends on ultraviolet-B dose but not on dose rate: A randomized controlled trial

Skin Color Change in Caucasian Postmenopausal Women Predicts Summer-Winter Change in 25-Hydroxyvitamin D: Findings from the ANSAViD Cohort Study

“…redness, and pigment protection factor (ratio of SED to minimal erythmal dose) (20). Our longer-term, free-living data support that there is no difference in mean 25(OH)D change between self-reported skin types I-III, although the latter had greater sunlight exposure in summer.…”

Vitamin D levels after UVB radiation: effects by UVA additions in a randomized controlled trial

“…Thus, if there were a photodegradation process instigated by UVA, 1 min is probably not long enough to initiate the degradation of Tables 3 and 4. We found that Δ25(OH)D was positively correlated to a low baseline value of 25(OH)D. Consequently, the increase of 25(OH)D was largest in the participants with the lowest baseline values, an observation reported previously (6,16,17). However, such a significant relationship could depend on the regression to the mean phenomenon.…”

Phototherapy with UVB narrowband, UVA/UVBnb, and UVA1 differentially impacts serum 25-hydroxyvitamin-D3

“…4,11,17 We did not find any correlation between the cumulative dose of UVBnb and the increase of serum 25(OH)D at 12 weeks, in accordance with Osmancevic et al 14 but in contradiction to a recent study. 18 The explanation might be that 25(OH)D reaches a plateau after 3 weeks already, and that exposure to additional UVBnb may not result in a continued proportional increase in serum vitamin D. UVBnb therapies but significant only under UVBbb therapy. 8,12,14 However we cannot exclude a significant PTH decrease with a greater patient number, as we observe a tendency towards a reduction of plasmatic PTH.…”