Sustained Increase of 25-Hydroxyvitamin D Levels in Healthy Young Women during Wintertime after Three Suberythemal UV Irradiations—The MUVY Pilot Study

Abstract

ObjectivesVitamin D (VitD) deficiency is a health problem prevalent not only in the elderly but also in young adults. The primary objective of our observational pilot study “MUVY” (Mood, UVR, Vitamin D in Young women) was to test both the short-term and long-term effects of a series of three suberythemal UV radiation (UVR) exposures on the VitD status and well-being of young healthy women during winter in a repeat measure design.Methods20 healthy young women (Fitzpatrick skin types I–III, aged 21–25 years) received three full body broad band UVR exposures with an escalating erythemally weighted dose schedule during one week in winter, and completed self-report questionnaires monitoring symptoms of depression (Beck Depression Inventory, BDI) and affective state/well-being (Profile of Mood States, POMS) at baseline and three days after the last UVR exposure. 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH)2D) were measured in serum at baseline, and at study days 8, 36 and 50.ResultsMean baseline 25(OH)D level was 54.3 nmol/L (standard deviation (s.d.) = 24.1), with seven women having VitD deficient status. Relevant symptoms of depression, as indicated by low BDI total scores (0–8), were absent. After the three UVR exposures the increment of 25(OH)D was an average of 13.9 nmol/L (95% confidence interval (CI) = 9.4–18.4) and 26.2 pmol/L (95%CI = 7.2–45.1) for 1,25(OH)2D. Δ25(OH)D, and corresponding baseline levels were significantly and inversely associated (rho = -0.493, p = 0.027). Only 25(OH)D remained significantly increased above baseline for at least six weeks after the last UVR exposure. A strong inverse correlation of the POMS subscale “Vigor/Activity” and the increment in 1,25(OH)2D was found (rho = -0.739, p<0.001) at day 8.ConclusionsThree suberythemal whole body UVR exposures during one week are a simple and suitable method for improving 25(OH)D levels during winter, for at least six weeks, and especially in young women with VitD deficient status.Trial RegistrationGerman Clinical Trials Register (Deutsches Register Kinischer Studien) DRKS00009274

100 YEARS OF VITAMIN D: Dose–response for change in 25-hydroxyvitamin D after UV exposure: outcome of a systematic review

“…Study ( 50 ) gave three doses on 3 consecutive days, which is similar to the first week of study ( 47 ) (three doses over 5 days), and with a similar total dose for 1 week. However, study ( 50 ) used whole-body radiation (~90% skin area) vs 35% for study ( 47 ).…”

“…Artificial UV exposure manuscripts (including data from the record using both sources ( 24 )) were reduced to 22 ( 20 , 24 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 ) mainly due to lack of sufficient information on UV source deployed, the exposure regime and/or lack of before and after 25OHD measurements. All remaining studies represented work with adult volunteers, provided with a course of standardised, artificial UV exposures, but UV source and dosing regime varied significantly between studies.…”

“…Study [48] provides a similar dose to [50], both as whole body irradiations. However, [48] is provided in one dose, and at a level that must be close to an MED for the participants, leading to the lower efficiency observed with other radiation sources when the dose is (too) high [41,43,60] Study [51] included some participants taking vitamin D supplements.…”

The Impact of UV-dose, Body Surface Area Exposed and Other Factors on Cutaneous Vitamin D Synthesis Measured as Serum 25(OH)D Concentration: Systematic Review and Meta-analysis

“…Note that some relevant features such as age, body mass index or skin type could not be considered because Figure 1. Flow chart of our literature search process that identified 15 papers [ (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25); 829 participants] published in the past 7 years, that were eligible for meta-analysis. information was missing, incomplete or not comparable.…”

UV “Indices”—What Do They Indicate?

“…We are somewhat relieved to realize that our misconception is encountered quite commonly (just to name a few recent examples, see [4,5,6]). Researchers must use the exposure parameters that are available and the erythemally weighted dose is most commonly provided and hence also used to study UV effects.…”