In the first report to our knowledge of CDC-accredited 25(OH)D data and pregnancy outcomes from a large, clinically validated, prospective cohort study, we observed a protective association of a 25(OH)D concentration >75 nmol/L and a reduced risk of uteroplacental dysfunction as indicated by a composite outcome of SGA and pre-eclampsia. Well-designed, adequately powered randomized controlled trials are required to verify this observation. The SCOPE pregnancy cohort was registered at www.anzctr.org.au as ACTRN12607000551493.

Nutritional requirements for vitamin D during pregnancy have been inadequately described, and there are conflicting data on the impact of gestation on vitamin D status. In the present study, we conducted a longitudinal analysis of total and free (unbound) serum 25-hydroxyvitamin D (25(OH)D), vitamin D-binding protein (DBP) and albumin concentrations in a random sample of thirty women from the Screening for Pregnancy Endpoints Ireland pregnancy cohort study at 15,20,24, 28, 32, 36 and 40 weeks of gestation and at 2 months postpartum. Concentrations of serum 25(OH)D, DBP and albumin were determined, and free 25(OH)D was calculated from the concentrations of total 25(OH)D, DBP and albumin. Serum albumin concentration decreased during pregnancy (P,0·001), with a nadir at 36 weeks (P,0·005), during which the concentration was approximately 80 % of the postnatal concentration. Serum DBP concentration increased during pregnancy and at 28 weeks of gestation, which was almost double the postnatal level (P, 0·001). Total and free 25(OH)D concentrations decreased (both P, 0·005) as pregnancy progressed, and both were lowest at 36 weeks of gestation. At 15 weeks, 10 and 63 % of the women had serum 25(OH)D concentration , 30 and 50 nmol/l, respectively, which increased to 53 and 80 % at 36 weeks of gestation. The time course of decreasing concentrations of 25(OH)D during gestation among women recruited during May -July, who delivered between October and November, and among those recruited in August -September, who delivered between February and March, was similar. The lower percentage of free 25(OH)D during pregnancy is mainly due to increased DBP. Pregnancy is a life stage at which significant changes in vitamin D and Ca metabolism occur to provide the required Ca to the fetus for bone mineral accretion; however, nutritional requirements for vitamin D to promote healthy pregnancy are not known. The current suggested cut-offs for serum 25-hydroxyvitamin D (25(OH)D) concentrations representing vitamin D sufficiency/deficiency are based on the evidence from non-pregnant adults; however, it remains to be established whether there is an increased requirement for vitamin D intake during pregnancy and lactation (1,2) . A challenge of assessing vitamin D status during pregnancy is haemodilution. The expansion of maternal plasma volume begins as early as 6 weeks of gestation and continues until it reaches a net 40 % increase at 24-34 weeks of gestation (3) and an approximately 50 % increase by 36 weeks of gestation (4) . Thus, circulating concentrations of most nutrients decrease by the end of the first 10 weeks of gestation and remain lower than non-pregnancy values until term, even though the absolute total amount of vitamins and minerals in the circulation actually increases during pregnancy (5) . The increased blood volume during pregnancy is evidenced by the reduction in the concentration of circulating serum albumin (6) . Reference values for serum 25(OH)D concentrations based on non-pregnant adults are not necessaril...

Mitigating human‐induced climate change calls for a globalized change of consciousness and practice. These global challenges also demand a double transformation of the social sciences – first, from ‘methodological nationalism’ to ‘methodological cosmopolitanism’ and, second, an empirical reorientation towards ‘cosmopolitization’ as the social force of emerging cosmopolitan realities. One of these realities is the possible emergence, locally and globally, of ‘cosmopolitan communities of climate risk’ in response to a ‘world at risk’. A key research question for contemporary social science is thus: how and where are new cosmopolitan communities of climate risk being imagined and realized? In this article, we propose and explore a research agenda formulated around this key question. We both develop a theoretical perspective and provide short empirical illustrations of case studies regarding ongoing research in Europe and East Asia on such cosmopolitan climate risk communities.

The Vitamin D Standardization Program (VDSP) coordinated an interlaboratory study to assess the comparability of measurements of total 25-hydroxyvitamin D [25(OH)D] in human serum, which is the primary marker of vitamin D status. A set of 50 individual donor samples were analyzed by 15 different laboratories representing national nutrition surveys, assay manufacturers, and clinical and/or research laboratories to provide results for total 25(OH)D using both immunoassays (IAs) and LC tandem MS (MS/MS). The results were evaluated relative to bias compared with the target values assigned based on a combination of measurements at Ghent University (Belgium) and the U.S. National Institute of Standards and Technology using reference measurement procedures for the determination of 25(OH)D2 and 25(OH)D3. CV and mean bias for each laboratory and assay platform were assessed and compared with previously established VDSP performance criteria, namely CV ≤ 10% and mean bias ≤ 5%. Nearly all LC-MS/MS results achieved VDSP criteria, whereas only 50% of IAs met the criterion for a ≤10% CV and only three of eight IAs achieved the ≤5% bias. These results establish a benchmark for the evaluation of 25(OH)D assay performance and standardization activities in the future.

We found no evidence of a vitamin D sparing effect of high calcium intake, which has been referred to by some authors as "vitamin D economy." Thus, recent dietary vitamin D requirement estimates will cover the vitamin D needs of even those individuals who have inadequate calcium intakes.