Traditionally living populations in East Africa have a mean serum 25-hydroxyvitamin D concentration of 115 nmol/l

Cutaneous synthesis of vitamin D by exposure to UVB is the principal source of vitamin D in the human body. Our current clothing habits and reduced time spent outdoors put us at risk of many insufficiency-related diseases that are associated with calcaemic and non-calcaemic functions of vitamin D. Populations with traditional lifestyles having lifelong, year-round exposure to tropical sunlight might provide us with information on optimal vitamin D status from an evolutionary perspective. We measured the sum of serum 25-hydroxyvitamin D2 and D3 (25(OH)D) concentrations of thirty-five pastoral Maasai (34 (sd 10) years, 43 % male) and twenty-five Hadzabe hunter–gatherers (35 (sd 12) years, 84 % male) living in Tanzania. They have skin type VI, have a moderate degree of clothing, spend the major part of the day outdoors, but avoid direct exposure to sunlight when possible. Their 25(OH)D concentrations were measured by liquid chromatography–MS/MS. The mean serum 25(OH)D concentrations of Maasai and Hadzabe were 119 (range 58–167) and 109 (range 71–171) nmol/l, respectively. These concentrations were not related to age, sex or BMI. People with traditional lifestyles, living in the cradle of mankind, have a mean circulating 25(OH)D concentration of 115 nmol/l. Whether this concentration is optimal under the conditions of the current Western lifestyle is uncertain, and should as a possible target be investigated with concomitant appreciation of other important factors in Ca homeostasis that we have changed since the agricultural revolution.

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Vitamin D Level Stability in Dystrophinopathy Patients on Vitamin D Supplementation

Journal of Neuromuscular Diseases ◽

10.3233/jnd-200625 ◽

2021 ◽

pp. 1-7

Author(s):

Naomi Vather-Wu ◽

Matthew D. Krasowski ◽

Katherine D. Mathews ◽

Amal Shibli-Rahhal

Keyword(s):

Vitamin D ◽

Retrospective Cohort ◽

Vitamin D Supplementation ◽

Hydroxyvitamin D ◽

Frequent Monitoring ◽

25 Hydroxyvitamin D ◽

The Mean ◽

Stable Maintenance ◽

Mean Time

Background: Expert guidelines recommend annual monitoring of 25-hydroxyvitamin D (25-OHD) and maintaining 25-OHD ≥30 ng/ml in patients with dystrophinopathies. Objective: We hypothesized that 25-OHD remains stable and requires less frequent monitoring in patients taking stable maintenance doses of vitamin D. Methods: We performed a retrospective cohort study, using the electronic health record to identify 26 patients with dystrophinopathies with a baseline 25-OHD ≥30 ng/mL and at least one additional 25-OHD measurement. These patients had received a stable dose of vitamin D for ≥3 months prior to their baseline 25-OHD measurement and throughout follow-up. The main outcome measured was the mean duration time the subjects spent with a 25-OHD ≥30 ng/mL. Results: Only 19% of patients dropped their 25-OHD to < 30 ng/ml, with a mean time to drop of 33 months and a median nadir 25-OHD of 28 ng/mL. Conclusions: These results suggest that measurement of 25-OHD every 2–2.5 years may be sufficient in patients with a baseline 25-OHD ≥30 ng/mL and who are on a stable maintenance dose of vitamin D. Other patients may require more frequent assessments.

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To screen or not to screen? Vitamin D deficiency in chronic mental illness

Australasian Psychiatry ◽

10.1177/1039856217726717 ◽

2017 ◽

Vol 26 (1) ◽

pp. 56-59

Author(s):

Ivana Goluza ◽

Jay Borchard ◽

Nalin Wijesinghe ◽

Kishan Wijesinghe ◽

Nagesh Pai

Keyword(s):

Vitamin D ◽

Length Of Stay ◽

P Value ◽

Hydroxyvitamin D ◽

Psychiatric Setting ◽

Retrospective Audit ◽

Vitamin D Levels ◽

Significant Difference ◽

25 Hydroxyvitamin D ◽

The Mean

Objectives: The objective of the current study was to examine the pathology test utilisation of 25-hydroxyvitamin D (25(OH)D) within an Australian inpatient psychiatric setting. Method: A retrospective audit of 300 random hospital files of those admitted as inpatients between Nov 2014 and Nov 2015 was undertaken. Data was quantitatively analysed and described. Results: The number of inpatients who had a vitamin D determination during their admission was 37/300 (12.33%). The mean vitamin D level of those tested was 51.63 nmol/l. Of those that were tested, 18/37 (48.6%) were mildly to moderately deficient. There was a statistically significant difference in age and length of stay between those that were and were not tested for vitamin D levels, p-value <0.001 and 0.017, respectively. In addition, a simple linear regression indicated a weak association between length of stay and vitamin D levels. Conclusion: This audit highlights vitamin D screening inadequacy. More research is recommended to establish tangible benefits of supplementation, while local practice provides valuable data for education and policy purposes.

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Determinants of serum 25-hydroxyvitamin D in Hong Kong

British Journal Of Nutrition ◽

10.1017/s0007114515001683 ◽

2015 ◽

Vol 114 (1) ◽

pp. 144-151 ◽

Cited By ~ 13

Author(s):

Cuiling Xu ◽

Ranawaka A. P. M. Perera ◽

Yap-Hang Chan ◽

Vicky J. Fang ◽

Sophia Ng ◽

...

Keyword(s):

Vitamin D ◽

Hong Kong ◽

Southern China ◽

Age Groups ◽

Dietary Vitamin ◽

Skeletal Health ◽

Mean Values ◽

Hydroxyvitamin D ◽

25 Hydroxyvitamin D ◽

The Mean

Vitamin D plays an important role in skeletal health throughout life. Some studies have hypothesised that vitamin D may reduce the risk of other diseases. Our study aimed to estimate age-specific and sex-specific serum 25-hydroxyvitamin D (25(OH)D) status and to identify the determinants of serum 25(OH)D status in Hong Kong, a subtropical city in southern China. In 2009–2010, households in Hong Kong were followed up to identify acute respiratory illnesses, and sera from 2694 subjects were collected in three to four different study phases to permit measurement of 25(OH)D levels at different times of the year. A questionnaire survey on diet and lifestyle was conducted among children, with simultaneous serum collection in April and May 2010. The mean of serum 25(OH)D levels in age groups ranged from 39 to 63 nmol/l throughout the year with the mean values in all age groups in spring below 50 nmol/l. Children aged 6–17 years, and girls and women had significantly lower serum 25(OH)D levels than adults, and boys and men, respectively (allP< 0·001). We estimated that serum 25(OH)D levels in Hong Kong followed a lagged pattern relative to climatic season by 5 weeks with lowest observed levels in early spring (March). For children aged 6–17 years, reporting a suntan, having at least 1 servings of fish/week and having at least 1 serving of eggs/week were independently associated with higher serum 25(OH)D levels. Adequate sunlight exposure and increased intake of dietary vitamin D could improve vitamin D status, especially for children and females in the winter and spring.

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Vitamin D Status among Young Children Aged 6 to 23 Months from 4 Different Ethnic Groups in Yunnan, China

Food and Nutrition Bulletin ◽

10.1177/0379572118765825 ◽

2018 ◽

Vol 39 (2) ◽

pp. 260-265

Author(s):

Yanhong Li ◽

Yan Li ◽

Xian Zhang ◽

Lin Zhao ◽

Liqin Chen ◽

...

Keyword(s):

Vitamin D ◽

Young Children ◽

Vitamin D Deficiency ◽

Ethnic Groups ◽

Venous Blood ◽

Hydroxyvitamin D ◽

Significant Difference ◽

25 Hydroxyvitamin D ◽

The Mean ◽

Venous Blood Sampling

Objectives: To determine the prevalence of vitamin D deficiency in 6- to 23-month-old children from 4 different ethnic groups, Han, Lisu, Hani, and Bai, in Yunnan Province of China. Methods: A large cohort of 938 young children aged 6 to 23 months who were living in Yunnan, China (23°28′-27°52′ N), were selected and recruited in this study. Venous-blood sampling was conducted in all the participants, and serum 25-hydroxyvitamin D [25(OH)D] levels were measured. The children’s physical status was measured. Results: General mean serum 25(OH)D level was 21.46 ± 7.95 ng/mL, which was obtained from a total of 938 cases. No significant difference was found in age, gender, height, and weight of participants from different ethnic groups. The mean 25(OH)D level was significantly lower in children of Lisu ethnic groups compared with that of Han and Hani participants, respectively ( P < .05). In addition, Bai children had lower 25(OH)D content than Hani children ( P < .001). Among the children with 25(OH)D sufficiency, the number of Lisu participants was significantly lower than Han children ( P < .001). Conclusion: The prevalence of vitamin D deficiency varied among the ethnically different children in Yunnan, China, and significantly fewer Lisu children maintained vitamin D sufficiency compared with other ethnic children. Recognizing these ethnic differences in treating children with vitamin D deficiency may improve the therapeutic outcome.

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The Prevalence of 25-Hydroxyvitamin D Deficiency in Post-HSCT Pediatric Patients.

Blood ◽

10.1182/blood.v112.11.2139.2139 ◽

2008 ◽

Vol 112 (11) ◽

pp. 2139-2139

Author(s):

Christine Duncan ◽

Lynda Vrooman ◽

Lori Bechard ◽

Elly Barry ◽

Leslie E. Lehmann

Keyword(s):

Vitamin D ◽

Vitamin D Deficiency ◽

Pediatric Patients ◽

Bone Marrow Failure ◽

Long Term Effects ◽

Hydroxyvitamin D ◽

Vitamin D Levels ◽

25 Hydroxyvitamin D ◽

The Mean ◽

25 Oh Vitamin D

Abstract Children undergoing HSCT are at risk for vitamin D deficiency due to lack of sun exposure, the recommended use of sunscreen, dietary insufficiency, and the effects of medications such as glucocorticoids and calcineurin inhibitors. We assessed the prevalence of 25-hydroxyvitamin D (25-OH vitamin D) deficiency in pediatric post-HSCT patients in an outpatient oncology clinic during 4 weeks in May 2008. Patients found to have low 25-OH vitamin D levels were referred for dietary counseling and given supplementation or repletion as needed. 25-OH vitamin D and parathyroid hormone (PTH) levels were measured in 62 (88.6%) of 70 eligible patients. 83.8% of patients had a 25-OH vitamin D level less than the institutional lower limit of normal, 30 ng/mL. 29% of patients were 25-OH vitamin D insufficient with levels 20–29 ng/mL (range of 20–29). 54.8% of patients were 25-OH vitamin D deficient with levels <20 ng/mL (range 5–19). The prevalence of insufficiency and deficiency was similar between male (87.8%; 57.6%) and female patients (57.6%; 55.2%).The mean duration of days following transplant was 532.6 days (median 251.5 days). The mean age at transplant was 3.7 years (median 3.5 years). 47% of patients were female. 75.8% were Caucasian. 90.3% received allogeneic transplants. The underlying diseases were as follows: ALL (27.4%), AML/MDS (24.2%), bone marrow failure (11.3%), nonmalignant hematologic diagnosis (8.1%), solid tumor (8.1%), immunodeficiency (6.5%), lymphoma (6.5%), and other diagnoses (8.1%). 8 patients regularly took either an over-the-counter multivitamin or vitamin D supplement and all 8 patients had 25-OH levels less than 30 ng/mL. There was a negative inverse correlation of (r= −0.3, p=0.029) between PTH and 25-OH vitamin D. There were no significant associations between 25-OH vitamin D level and any of the following: corticosteroid or calcineurin inhibitor use in the preceding year, time from transplant, age at transplant, current age, or graft-versus-host disease. 25-OH vitamin D insufficiency and deficiency are common following pediatric HSCT. We recommend vitamin D screening for all post-HSCT pediatric patients. Further investigation is needed to identify potential risk factors for vitamin D deficiency and the long-term effects of deficiency on bone health and development.

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Prognostic effects of 25-hydroxyvitamin d levels in gastric cancer.

Journal of Clinical Oncology ◽

10.1200/jco.2012.30.15_suppl.e14653 ◽

2012 ◽

Vol 30 (15_suppl) ◽

pp. e14653-e14653

Author(s):

Chao Ren ◽

Rui-hua Xu

Keyword(s):

Gastric Cancer ◽

Vitamin D ◽

Gastric Cancer Cell ◽

Clinical Stage ◽

Epidemiologic Studies ◽

Hydroxyvitamin D ◽

Vitamin D Levels ◽

25 Hydroxyvitamin D ◽

The Mean ◽

Stored Blood

e14653 Background: Results from large epidemiologic studies on the association between vitamin D and gastric cancer are controversial. Vitamin D significantly promotes apoptosis in the undifferentiated gastric cancer cell, but the prognostic effects of its levels are unknown. Methods: 197 gastric carcinoma patients who received treatment in the cancer centre of Sun Yat-sen University from January 2002 to January 2006 were involved in the study. The stored blood drawn before any treatment was assayed for 25-hydroxyvitamin D levels. The clinicopathologic data were collected to examine the prognostic effects of vitamin D. Results: The mean vitamin D levels of the 197 gastric patients was 49.85±23.68nmol/L, among whom 114(57.9%) were deficient in Vitamin D(<50nmol/L), 67(34%) were insufficient (50-75nmol/L) and 16(8.1%) were sufficient (>75nmol/L). Clinical stage (p=0.004) and lymph node metastasis classification (p=0.009) were inversely associated with vitamin D levels. The patients with high vitamin D levels group (≥50nmol/L) had a higher overall survival compared with the low vitamin D levels group (<50nmol/L)(p=0.018). Multivariate analysis indicated that vitamin D levels were an independent prognostic factor of gastric cancer (p=0.019). Conclusions: Vitamin D deficiency may be associated with poor prognosis in gastric cancer.

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Circulating 25-Hydroxyvitamin D Levels in Fully Breastfed Infants on Oral Vitamin D Supplementation

International Journal of Endocrinology ◽

10.1155/2010/235035 ◽

2010 ◽

Vol 2010 ◽

pp. 1-5 ◽

Cited By ~ 22

Author(s):

Carol L. Wagner ◽

Cindy Howard ◽

Thomas C. Hulsey ◽

Ruth A. Lawrence ◽

Sarah N. Taylor ◽

...

Keyword(s):

Vitamin D ◽

Vitamin D Supplementation ◽

Vitamin Supplementation ◽

Oral Vitamin ◽

Oil Emulsion ◽

Hydroxyvitamin D ◽

Breastfed Infants ◽

25 Hydroxyvitamin D ◽

The Mean ◽

Nutritional Vitamin

Objective. To examine the effectiveness of oral vitamin (400 IU) supplementation on the nutritional vitamin D status of breastfeeding infants.Design. As part of a larger ongoing vitamin D RCT trial of lactating women, infants of mothers assigned to control received 1 drop of 400 IU vitamin /day starting at one month of age. Infant 25(OH)D levels (mean S.D.) were measured by RIA at visits 1, 4, and 7.Results. The infant mean S.D. 25(OH)D at baseline was 16.0 9.3 ng/mL (range 1.0–40.8; ); 24 (72.7%) had baseline levels <20 ng/mL (consistent with deficiency). The mean levels increased to 43.6 14.1 (range 18.2–69.7) at 4 months and remained relatively unchanged at month 7: 42.5 12.1 ng/mL (range 18.9–67.2). The change in values between 1 and 4 months and 1 and 7 months was statistically significant , and despite a decrease in dose per kilogram, values were not significantly different between months 4 and 7 .Conclusions. Oral vitamin supplementation as an oil emulsion was associated with significant and sustained increases in 25(OH)D from baseline in fully breastfeeding infants through 7 months.

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Vitamin D Dosing Strategies Among Jordanians With Hypovitaminosis D

Journal of Pharmacy Practice ◽

10.1177/0897190015626334 ◽

2016 ◽

Vol 30 (2) ◽

pp. 172-179 ◽

Cited By ~ 1

Author(s):

Nahla Khawaja ◽

Mohammed Liswi ◽

Mohammed El-Khateeb ◽

Dana Hyassat ◽

Dalila Bajawi ◽

...

Keyword(s):

Body Mass Index ◽

Vitamin D ◽

Hypovitaminosis D ◽

Hydroxyvitamin D ◽

Dosing Strategies ◽

Optimal Maintenance ◽

Group A ◽

25 Hydroxyvitamin D ◽

The Mean ◽

Group B

Objective: To compare between weekly and daily cholecalciferol in patients with hypovitaminosis D and to determine the optimal maintenance dose. Methods: Seventy-one volunteers with hypovitaminosis D were randomly assigned to 2 dose regimens: cholecalciferol 50 000 IU weekly for 8 weeks, then 50 000 IU monthly for 2 months (group A) and 7000 IU daily for 8 weeks, then 12 500 IU weekly for 2 months (group B). Cholecalciferol was stopped for 2 months and reintroduced as 50 000 IU bimonthly for group A and 50 000 IU monthly for group B. Results: Two months after therapy, the mean serum 25-hydroxyvitamin D (25(OH)D) level increased from 11.4 to 51.2 ng/mL and from 11.7 to 44.9 ng/mL in groups A and B, respectively ( P = .065). The levels of 25(OH)D declined similarly in both groups during maintenance and after holding therapy. After resuming cholecalciferol, 25(OH)D levels increased to 33.8 and 28.8 ng/mL in groups A and B, respectively ( P = .027). There was a negative correlation between serum 25(OH)D levels and body mass index (BMI; P = .040). Conclusion: Timing and frequency of the dosing (daily vs weekly) have no effect on the rise in serum 25(OH)D levels as long as the accumulative dose of cholecalciferol is similar. Cholecalciferol 50 000 IU bimonthly is required to maintain sufficient 25(OH)D levels.

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Evaluation of 25-Hydroxyvitamin D Levels in Central Anatolia, Turkey

BioMed Research International ◽

10.1155/2018/4076548 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Ibrahim Solak ◽

Fatma Goksin Cihan ◽

Seher Mercan ◽

Tugba Kethuda ◽

Mehmet Ali Eryılmaz

Keyword(s):

Vitamin D ◽

Cost Effective ◽

Vitamin D Insufficiency ◽

Current Approach ◽

Central Anatolia ◽

Hydroxyvitamin D ◽

25 Hydroxyvitamin D ◽

The Mean ◽

One Year ◽

A Current

Background/Aim. The aim of this study is to evaluate serum 25-hydroxyvitamin D levels measured within one year at an Education and Research Hospital in Turkey to identify vitamin D insufficiency/deficiency (which is very commonly seen in the society) and to provide a current approach to treatment management. Materials and Methods. This retrospective descriptive study was carried out by examining the data relating to 35,667 individuals. Results. Of the individuals participating in the study, 94.47% had a serum 25-hydroxyvitamin D level less than 30 ng/ml, 76.25% had a serum 25-hydroxyvitamin D level less than 20 ng/ml, and 32.20% had a serum 25-hydroxyvitamin D level less than 10 ng/ml. The mean serum 25-hydroxyvitamin D level of all individuals included in the study was 15.2±8.8 ng/ml. The mean serum 25-hydroxyvitamin D level was 14.5±8.8 ng/ml among women and 18.1±8.4 ng/ml among men, respectively (p<0.001). Conclusion. Vitamin D deficiency/insufficiency is widespread in the world and in Turkey. The data obtained from this study suggest that without measuring serum 25-hydroxyvitamin D level will be cost-effective in every age group (except for those are at risk of toxicity) as in children aged 0-1 year old in Turkey and that making a decision in this direction will make a great contribution to the economy of the country.

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Serum 25-Hydroxyvitamin D Concentrations in Sudden Infant Death Syndrome

PEDIATRICS ◽

10.1542/peds.65.6.1137 ◽

1980 ◽

Vol 65 (6) ◽

pp. 1137-1139

Author(s):

Laura S. Hillman ◽

Marilyn Erickson ◽

John G. Haddad

Keyword(s):

Vitamin D ◽

Vitamin D Deficiency ◽

Sudden Infant Death Syndrome ◽

Infant Death ◽

Sudden Infant Death ◽

Near Miss ◽

Sudden Infant ◽

Hydroxyvitamin D ◽

25 Hydroxyvitamin D ◽

The Mean

Among the many theories put forth to explain sudden infant death syndrome (SIDS) is a theory of vitamin D deficiency. 25-Hydroxyvitamin D (25-OHD) serum concentrations were measured in 31 SIDS and 24 postmortem control infants. 25-OHD was 19.0 ± 7.9 mg/ml in SIDS, 16.9 ± 5.2 ng/ml in acute death control infants, and 11.9 ± 4.4 ng/ml in in-hospital deaths. For four "near miss" infants the mean serum 25-OHD concentration was 21.1 ± 4.1 ng/ml. The mean serum 25-OHD concentration of 39 living premature or small-for-gestational-age infants at 3 months of age was 26 ± 9.9. Serum calcium and serum copper concentrations were also the same in SIDS and control infants. Parathyroid hormone was measured in ten and was detectable in five SIDS infants. These data eliminate a simple vitamin D deficiency or a 25-OHD deficiency as a significant contribution to the pathophysiology of SIDS.

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