Measurement of 25-hydroxyvitamin D in serum and its relation to sunshine, age and vitamin D intake in the Danish population

AbstractInsufficient vitamin D status (serum 25-hydroxyvitamin D (S-25(OH)D)<50 nmol/l) is common among immigrants living at the northern latitudes. We investigated ethnic differences in response of S-25(OH)D to vitamin D3 supplementation, through a 5-month randomised controlled trial, in East African and Finnish women in Southern Finland (60°N) from December 2014 to May 2015. Vitamin D intakes (dietary and supplemental) were also examined. Altogether, 191 subjects were screened and 147 women (East Africans n 72, Finns n 75) aged 21–64 years were randomised to receive placebo or 10 or 20 µg of vitamin D3/d. S-25(OH)D concentrations were assessed by liquid chromatography–tandem MS. At screening, 56 % of East Africans and 9 % of Finns had S-25(OH)D<50 nmol/l. Total vitamin D intake was higher in East Africans than in Finns (24·2 (sd 14·3) v. 15·2 (sd 13·4) µg/d, P<0·001). Baseline mean S-25(OH)D concentrations were higher in Finns (60·5 (sd=16·3) nmol/l) than in East Africans (51·5 (sd 15·4) nmol/l) (P=0·001). In repeated-measures ANCOVA (adjusted for baseline S-25(OH)D), mean S-25(OH)D increased by 8·5 and 10·0 nmol/l with a 10-µg dose and by 10·7 and 17·1 nmol/l with a 20-µg dose for Finns and East Africans, respectively (P>0·05 for differences between ethnic groups). In conclusion, high prevalence of vitamin D insufficiency existed among East African women living in Finland, despite higher vitamin D intake than their Finnish peers. Moderate vitamin D3 supplementation was effective in increasing S-25(OH)D in both groups of women, and no ethnic differences existed in the response to supplementation.

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Insufficient autumn vitamin D intake and low vitamin D status in 7-year-old Icelandic children

Public Health Nutrition ◽

10.1017/s1368980013003558 ◽

2014 ◽

Vol 18 (2) ◽

pp. 208-217 ◽

Cited By ~ 6

Author(s):

Adda Bjarnadottir ◽

Asa Gudrun Kristjansdottir ◽

Hannes Hrafnkelsson ◽

Erlingur Johannsson ◽

Kristjan Thor Magnusson ◽

...

Keyword(s):

Vitamin D ◽

Cardiorespiratory Fitness ◽

Sunlight Exposure ◽

Vitamin D Status ◽

Blood Samples ◽

Hydroxyvitamin D ◽

Vitamin D Intake ◽

School Based ◽

25 Hydroxyvitamin D ◽

Vitamin D Supplements

AbstractObjectiveThe aim was to investigate autumn vitamin D intake and status in 7-year-old Icelanders, fitting BMI and cardiorespiratory fitness as predictors.DesignThree-day food records and fasting blood samples were collected evenly from September to November, and cardiorespiratory fitness was measured with an ergometer bike. Food and nutrient intakes were calculated, and serum 25-hydroxyvitamin D (s-25(OH)D) and serum parathyroid hormone were analysed. Suboptimal vitamin D status was defined s-25(OH)D <50 nmol/l, and deficient status as s-25(OH)D <25 nmol/l.SettingSchool-based study in Reykjavik, Iceland in 2006.SubjectsOf the 7-year-olds studied (n 265), 165 returned valid intake information (62 %), 158 gave blood samples (60 %) and 120 gave both (45 %).ResultsRecommended vitamin D intake (10 μg/d) was reached by 22·4 % of the children and 65·2 % had s-25(OH)D <50 nmol/l. Median s-25(OH)D was higher for children taking vitamin D supplements (49·2 nmol/l v. 43·2 nmol/l, respectively; P < 0·0 0 1). Median s-25(OH)D was lower in November (36·7 nmol/l) than in September (59·9 nmol/l; P < 0·001). The regression model showed that week of autumn accounted for 18·9 % of the variance in s-25(OH)D (P < 0·001), vitamin D intake 5·2 % (P < 0·004) and cardiorespiratory fitness 4·6 % (P < 0·005).ConclusionsA minority of children followed the vitamin D recommendations and 65 % had suboptimal vitamin D status during the autumn. Week of autumn was more strongly associated with vitamin D status than diet or cardiorespiratory fitness, which associated with vitamin D status to a similar extent. These results demonstrate the importance of sunlight exposure during summer to prevent suboptimal vitamin D status in young schoolchildren during autumn in northern countries. An increased effort is needed for enabling adherence to the vitamin D recommendations and increasing outdoor activities for sunlight exposure.

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Recommended intakes of vitamin D to optimise health, associated circulating 25-hydroxyvitamin D concentrations, and dosing regimens to treat deficiency: workshop report and overview of current literature

Journal of Nutritional Science ◽

10.1017/jns.2015.10 ◽

2015 ◽

Vol 4 ◽

Cited By ~ 33

Author(s):

Michiel G. J. Balvers ◽

Elske M. Brouwer-Brolsma ◽

Silvia Endenburg ◽

Lisette C. P. G. M. de Groot ◽

Frans J. Kok ◽

...

Keyword(s):

Vitamin D ◽

The Netherlands ◽

Vitamin D Deficiency ◽

Vitamin D Status ◽

Hydroxyvitamin D ◽

Vitamin D Intake ◽

Skeletal Disease ◽

Health Council ◽

Dosing Regimens ◽

25 Hydroxyvitamin D

AbstractVitamin D is a fat-soluble hormone that traditionally has been linked to bone health. Recently, its involvement has been extended to other (extra-skeletal) disease areas, such as cancer, CVD, energy metabolism and autoimmune diseases. Vitamin D deficiency is a worldwide problem, and several recommendation-setting bodies have published guidelines for adequate vitamin D intake and status. However, recommendations from, for example, the Health Council of the Netherlands do not provide advice on how to treat vitamin D deficiency, a condition that is often encountered in the clinic. In addition, these recommendations provide guidelines for the maintenance of ‘minimum levels’, and do not advise on ‘optimum levels’ of vitamin D intake/status to further improve health. The NutriProfiel project, a collaboration between the Gelderse Vallei Hospital (Ede, the Netherlands) and the Division of Human Nutrition of Wageningen University (Wageningen, the Netherlands), was initiated to formulate a protocol for the treatment of vitamin deficiency and for the maintenance of optimal vitamin D status. To discuss the controversies around treatment of deficiency and optimal vitamin D status and intakes, a workshop meeting was organised with clinicians, scientists and dietitians. In addition, a literature review was conducted to collect recent information on optimal intake of vitamins, their optimal circulating concentrations, and effective dosing regimens to treat deficiency. This information has been translated into the NutriProfiel advice, which is outlined in this article.

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Vitamin D Status in Japanese Adults: Relationship of Serum 25-Hydroxyvitamin D with Simultaneously Measured Dietary Vitamin D Intake and Ultraviolet Ray Exposure

Nutrients ◽

10.3390/nu12030743 ◽

2020 ◽

Vol 12 (3) ◽

pp. 743 ◽

Cited By ~ 2

Author(s):

Keiko Asakura ◽

Norihito Etoh ◽

Haruhiko Imamura ◽

Takehiro Michikawa ◽

Takahiro Nakamura ◽

...

Keyword(s):

Vitamin D ◽

Exposure Time ◽

Serum Vitamin ◽

Vitamin D Insufficiency ◽

Uv Exposure ◽

Dietary Vitamin ◽

Hydroxyvitamin D ◽

Vitamin D Intake ◽

25 Hydroxyvitamin D ◽

Ultraviolet Ray

Vitamin D insufficiency/deficiency is prevalent worldwide. We investigated the effect of vitamin D intake and ultraviolet ray (UV) exposure on serum vitamin D concentration in Japan. A total of 107 healthy adult participants were recruited from Hokkaido (43° N) and Kumamoto (33° N) prefectures. All participants undertook surveys in both summer and winter. Serum 25-hydroxyvitamin D (25(OH)D3) was examined, and vitamin D intake was assessed with a diet history questionnaire. UV exposure was measured with a wearable UV dosimeter. Regression analysis was performed to investigate the relationship between these factors, with covariates such as sun avoidance behavior. The prevalence of vitamin D insufficiency (serum 25(OH)D3; 12 ng/mL (30 nmol/L) ≤ and <20 ng/mL (50 nmol/L))/deficiency (<12 ng/mL) was 47.7% in summer and 82.2% in winter. UV exposure time was short in Kumamoto (the urban area), at 11.6 min in summer and 14.9 min in winter. In Hokkaido (the rural area), UV exposure time was 58.3 min in summer and 22.5 min in winter. Vitamin D intake was significantly associated with serum 25(OH)D3, and a 1 μg/1000kcal increase in intake was necessary to increase 25(OH)D3 by 0.88 ng/mL in summer and by 1.7 ng/mL in winter. UV exposure time was significantly associated with serum 25(OH)D3 in summer, and a 10 min increase in UV exposure time was necessary to increase 25(OH)D3 by 0.47 ng/mL. Although consideration of personal occupation and lifestyle is necessary, most Japanese may need to increase both vitamin D intake and UV exposure.

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