scholarly journals Suppression of Parathyroid Hormone as a Proxy for Optimal Vitamin D Status: Further Analysis of Two Parallel Studies in Opposite Latitudes

Nutrients ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 942 ◽  
Author(s):  
Marcela M. Mendes ◽  
Kathryn H. Hart ◽  
Susan A. Lanham-New ◽  
Patrícia B. Botelho
Keyword(s):  
Vitamin D ◽  
Parathyroid Hormone ◽  
Total Sample ◽  
Vitamin D Insufficiency ◽  
Vitamin D Supplementation ◽  
Vitamin D Status ◽  
Low Latitude ◽  
Vitamin D Levels ◽  
Cubic Model ◽  
The Relationship

Optimal vitamin D status has commonly been defined as the level of 25-hydroxyvitamin D (25(OH)D) at which parathyroid hormone (PTH) concentrations would be maximally suppressed, represented by an observed minimum plateau. Previous findings indicate a large variation in this plateau, with values ranging from <30 nmol/L up to 100 nmol/L. This disparity in values might be explained by differences in study design and methodology, ethnicity, age, gender and latitude. This study aimed to investigate the concentration of 25(OH)D at which PTH concentrations were suppressed in Brazilian women living in opposite latitudes (high vs. low: i.e., UK and Brazil), during wintertime. Using data from the D-SOL study (Interaction between Vitamin D Supplementation and Sunlight Exposure in Women Living in Opposite Latitudes), the association between 25(OH)D status and PTH levels were examined in 135 Brazilian women (56 living in England and 79 living in Brazil, aged 20–59 years old). Mean PTH concentrations for Brazilian women with vitamin D deficiency (<25 nmol/L) were significantly higher compared to those with vitamin D insufficiency (25–49.9 nmol/L) (p < 0.01), vitamin D adequacy (50–74.9 nmol/L) (p < 0.01) and those with optimal vitamin D status (>75 nmol/L) (p < 0.001). Regression modelling was used to investigate the relationship between serum 25(OH)D and PTH for the sample as a whole and for each group separately. A cubic model was statistically significant for the total sample (p < 0.001), whereas a linear model presented the best fit for Brazilian women living in England (p = 0.04) and there were no statistically significant models fitted for Brazilian women living in Brazil. The cubic model suggests that 25(OH)D concentrations above 70–80 nmol/L are optimal to suppress the parathyroid gland in Brazilian women. These findings contribute to a better understanding of the relationship between 25(OH)D and PTH in populations living in a low latitude location and are of great relevance for discussions regarding the estimation of optimal cut-offs for vitamin D levels in the Brazilian population as well as for other low latitude locations.

Correlation between vitamin D levels and hard-to-heal wounds: a systematic review

2020 ◽  
Vol 29 (Sup7) ◽  
pp. S24-S30 ◽  
Author(s):  
Karen Smith ◽  
Susan Hewlings
Keyword(s):  
Vitamin D ◽  
Financial Burden ◽  
Vitamin D Supplementation ◽  
Nutritional Deficiencies ◽  
Vitamin D Status ◽  
Hydroxyvitamin D ◽  
Venous Ulcers ◽  
Vitamin D Levels ◽  
25 Hydroxyvitamin D ◽  
The Relationship

Objective: Hard-to-heal wounds are a major biological, psychological, social and financial burden on both individual patients and the broader health system. They are associated with a variety of comorbidities and have a complex aetiology, but are typically associated with nutritional deficiencies, such as low vitamin D levels. This systematic literature review evaluates the current research regarding the connection between inadequate vitamin D status and wound healing. Method: PubMed and EBSCO databases were searched following PRISMA guidelines for primary research studies relating to pressure ulcers, diabetic ulcers or venous ulcers and vitamin D status. Results: A total of 10 studies, involving 2359 participants, met the inclusion criteria. There was a strong correlation between low levels of 25-hydroxyvitamin D and the presence of all three types of hard-to-heal wounds. Conclusion: Research suggests a correlation between low vitamin D levels and hard-to-heal wounds. However, it is not clear if the relationship is causal or only correlational. There is also emerging evidence on the use of vitamin D supplementation for the treatment of hard-to-heal wounds. More research is needed to understand the correlation between vitamin D and hard-to-heal wounds.

Correlation between vitamin D levels and hard-to-heal wounds: a systematic review

2021 ◽  
Vol 30 (Sup6) ◽  
pp. S4-S10
Author(s):  
Karen Smith ◽  
Susan Hewlings
Keyword(s):  
Vitamin D ◽  
Financial Burden ◽  
Vitamin D Supplementation ◽  
Nutritional Deficiencies ◽  
Vitamin D Status ◽  
Hydroxyvitamin D ◽  
Venous Ulcers ◽  
Vitamin D Levels ◽  
25 Hydroxyvitamin D ◽  
The Relationship

Objective: Hard-to-heal wounds are a major biological, psychological, social and financial burden on both individual patients and the broader health system. They are associated with a variety of comorbidities and have a complex aetiology, but are typically associated with nutritional deficiencies, such as low vitamin D levels. This systematic literature review evaluates the current research regarding the connection between inadequate vitamin D status and wound healing. Method: PubMed and EBSCO databases were searched following PRISMA guidelines for primary research studies relating to pressure ulcers, diabetic ulcers or venous ulcers and vitamin D status. Results: A total of 10 studies, involving 2359 participants, met the inclusion criteria. There was a strong correlation between low levels of 25-hydroxyvitamin D and the presence of all three types of hard-to-heal wounds. Conclusion: Research suggests a correlation between low vitamin D levels and hard-to-heal wounds. However, it is not clear if the relationship is causal or only correlational. There is also emerging evidence on the use of vitamin D supplementation for the treatment of hard-to-heal wounds. More research is needed to understand the correlation between vitamin D and hard-to-heal wounds.

scholarly journals The Relationship between Vitamin D Status and Rotator Cuff Muscle Strength in Professional Volleyball Athletes

Nutrients ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2768 ◽  
Author(s):  
Do Kyung Kim ◽  
Geon Park ◽  
Liang-Tseng Kuo ◽  
Won Hah Park
Keyword(s):  
Vitamin D ◽  
Muscle Strength ◽  
Vitamin D Insufficiency ◽  
Vitamin D Status ◽  
Shoulder Muscle ◽  
Vitamin D Levels ◽  
Volleyball Players ◽  
The Relationship ◽  
Shoulder Muscle Strength ◽  
External Rotator

This study aimed to examine the vitamin D status of professional volleyball athletes and to determine its correlation with shoulder muscle strength. We included 52 healthy male professional volleyball players (23.2 ± 4.5 years), who were categorized by vitamin D status (<20 ng/mL: deficiency, 20–30 ng/mL: insufficiency, and >30 ng/mL: sufficiency). We examined the strength of the internal rotator (IR) and external rotator (ER) muscles of the shoulder by using an isokinetic dynamometer. Fourteen players (26.9%) had vitamin D deficiency, 24 players (46.2%) were vitamin D-insufficient, and 14 players (26.9%) were vitamin D-sufficient. There was no significant correlation between vitamin D level and shoulder muscle strength at 60°/s (IR, r = 0.159, p = 0.26; ER, r = 0.245, p = 0.08) and at 180°/s (IR, r = −0.093, p = 0.51; ER, r = −0.037, p = 0.79). Moreover, the isokinetic shoulder strengths were not significantly different across the three groups in all settings. In conclusion, vitamin D insufficiency was common in elite volleyball players. Though not being associated with isokinetic muscle weakness, vitamin D levels should be regularly monitored, and vitamin D should be supplied to young elite athletes, considering its importance for musculoskeletal health.

scholarly journals Vitamin D Status in Pediatric and Young Adult Cystic Fibrosis Patients. Are the New Recommendations Effective?

Nutrients ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 4413
Author(s):  
Carmen Mangas-Sánchez ◽  
María Garriga-García ◽  
María Juliana Serrano-Nieto ◽  
Ruth García-Romero ◽  
Marina Álvarez-Beltrán ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Vitamin D ◽  
Vitamin D Insufficiency ◽  
Vitamin D Supplementation ◽  
Vitamin D Status ◽  
Safety And Efficacy ◽  
Vitamin D Levels ◽  
25 Oh Vitamin D ◽  
New Guidelines ◽  
Higher Doses

Introduction: In recent years, guidelines for vitamin D supplementation have been updated and prophylactic recommended doses have been increased in patients with cystic fibrosis (CF). Objective: To evaluate safety and efficacy of these new recommendations. Results: Two cohorts of pancreatic insufficient CF patients were compared before (cohort 1: 179 patients) and after (cohort 2: 71 patients) American CF Foundation and European CF Society recommendations were published. Cohort 2 patients received higher Vitamin D doses: 1509 (1306–1711 95% CI) vs 1084 (983–1184 95% CI) IU/Day (p < 0.001), had higher 25 OH vitamin D levels: 30.6 (27.9–33.26 95% CI) vs. 27.4 (25.9–28.8 95% CI) ng/mL (p = 0.028), and had a lower prevalence of insufficient vitamin D levels (<30 ng/mL): 48% vs 65% (p = 0.011). Adjusted by confounding factors, patients in cohort 1 had a higher risk of vitamin D insufficiency: OR 2.23 (1.09–4.57 95% CI) (p = 0.028). Conclusion: After the implementation of new guidelines, CF patients received higher doses of vitamin D and a risk of vitamin D insufficiency decreased. Despite this, almost a third of CF patients still do not reach sufficient serum calcidiol levels.

Questioning the adequacy of standardized vitamin D supplementation protocol in very low birth weight infants: a prospective cohort study

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Hatice Sarıdemir ◽  
Ozge Surmeli Onay ◽  
Ozge Aydemir ◽  
Ayse Neslihan Tekin
Keyword(s):  
Vitamin D ◽  
Cohort Study ◽  
Birth Weight ◽  
Low Birth Weight ◽  
Prospective Cohort ◽  
Very Low Birth Weight ◽  
Vitamin D Supplementation ◽  
Vitamin D Status ◽  
Vlbw Infants ◽  
Vitamin D Levels

Abstract Objectives Preterm infants are at increased risk for vitamin D deficiency (VDD). We aimed to assess the adequacy of standardized vitamin D supplementation protocol in very low birth weight (VLBW) infants. Additionally, vitamin D status of mother/infant couples and the associations between vitamin D status at birth and morbidities of the infants were investigated. Methods In this single-center, prospective cohort study blood samples were collected from 55 mothers just before delivery and from their infants at birth and on the 30th day of life (DOL) for 25 hydroxy vitamin D (25OHD) measurements. Vitamin D was initiated in dose of 160 IU/kg by parenteral nutrition on the first DOL and oral vitamin D supplementation (400 IU/day) was administered when enteral feedings reached 50% of total intake or on the 15th DOL. Results The median 25OHD levels of the infants were 16.12 (9.14–20.50) in cord blood and 36.32 (31.10–44.44) in venous blood on the 30th DOL (p<0.01). In 98% of the VLBW infants 25OHD reached sufficient levels on the 30th DOL. None of the mothers had sufficient vitamin D levels (25OHD >30 ng/mL). Maternal 25OHD levels were correlated with the 25OHD levels of the infants in cord blood (r=0.665, p<0.001). There was a significant difference in mean cord 25OHD levels between winter (13.65 ± 5.69 ng/mL) and summer seasons (19.58 ± 11.67 ng/mL) (p=0.021). No association was found between neonatal morbidity and vitamin D status. Conclusions The results clearly show that by utilizing the current supplementation protocol, the majority of VLBW infants with deficient/insufficient serum 25OHD levels reached sufficient levels on the 30th DOL. Furthermore, vitamin D levels in mother/infant couples were found to be highly correlated.

scholarly journals Effect of Vitamin D Status during Pregnancy on Infant Neurodevelopment: The ECLIPSES Study

Nutrients ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 3196
Author(s):  
Núria Voltas ◽  
Josefa Canals ◽  
Carmen Hernández-Martínez ◽  
Núria Serrat ◽  
Josep Basora ◽  
...  
Keyword(s):  
Vitamin D ◽  
Motor Skills ◽  
Infant Development ◽  
First Trimester ◽  
Vitamin D Supplementation ◽  
Vitamin D Status ◽  
Postpartum Visit ◽  
Neurodevelopmental Outcomes ◽  
Vitamin D Levels ◽  
Infant Neurodevelopment

Vitamin D status during pregnancy is involved in numerous physiological processes, including brain development. In this study, we assess the association between vitamin D status during pregnancy and infant neurodevelopment (cognitive, language, and motor skills). From an initial sample of 793 women (mean age 30.6) recruited before the 12th week of pregnancy, 422 mother–infant pairs were followed up to a postpartum visit. Vitamin D levels were assessed in the first and third trimesters of pregnancy, and socio-demographic, nutritional, and psychological variables were collected. At 40 days postpartum, the Bayley Scales of Infant Development-III were administered to the infants and several obstetrical data were recorded. Independently from several confounding factors, deficient vitamin D levels in the first trimester of pregnancy (<30 nmol/L) predicted a worse performance in cognitive and language skills. Language performance worsened with lower vitamin D levels (<20 nmol/L). In the third trimester, this highly deficient level was also associated with lower motor skills. Vitamin D deficiency was therefore associated with worse neurodevelopmental outcomes. More studies are needed to determine specific recommendations with regard to vitamin D supplementation during pregnancy in order to promote an optimal course for pregnancy and optimal infant neurodevelopment.

scholarly journals Role of pregnancy and obesity on vitamin D status, transport, and metabolism in baboons

2019 ◽  
Vol 316 (1) ◽  
pp. E63-E72
Author(s):  
Eugenia Mata-Greenwood ◽  
Hillary F. Huber ◽  
Cun Li ◽  
Peter W. Nathanielsz
Keyword(s):  
Vitamin D ◽  
Maternal Obesity ◽  
Subcutaneous Fat ◽  
Placental Tissue ◽  
Vitamin D Insufficiency ◽  
Primate Species ◽  
Vitamin D Status ◽  
Vitamin D Levels ◽  
25 Hydroxy Vitamin D ◽  
Kidney Liver

Human studies show that obesity is associated with vitamin D insufficiency, which contributes to obesity-related disorders. Our aim was to elucidate the regulation of vitamin D during pregnancy and obesity in a nonhuman primate species. We studied lean and obese nonpregnant and pregnant baboons. Plasma 25-hydroxy vitamin D (25-OH-D) and 1α,25-(OH)2-D metabolites were analyzed using ELISA. Vitamin D-related gene expression was studied in maternal kidney, liver, subcutaneous fat, and placental tissue using real-time PCR and immunoblotting. Pregnancy was associated with an increase in plasma bioactive vitamin D levels compared with nonpregnant baboons in both lean and obese groups. Pregnant baboons had lower renal 24-hydroxylase CYP24A1 protein and chromatin-bound vitamin D receptor (VDR) than nonpregnant baboons. In contrast, pregnancy upregulated the expression of CYP24A1 and VDR in subcutaneous adipose tissue. Obesity decreased vitamin D status in pregnant baboons (162 ± 17 vs. 235 ± 28 nM for 25-OH-D, 671 ± 12 vs. 710 ± 10 pM for 1α,25-(OH)2-D; obese vs. lean pregnant baboons, P < 0.05). Lower vitamin D status correlated with decreased maternal renal expression of the vitamin D transporter cubulin and the 1α-hydroxylase CYP27B1. Maternal obesity also induced placental downregulation of the transporter megalin (LRP2), CYP27B1, the 25-hydroxylase CYP2J2, and VDR. We conclude that baboons represent a novel species to evaluate vitamin D regulation. Both pregnancy and obesity altered vitamin D status. Obesity-induced downregulation of vitamin D transport and bioactivation genes are novel mechanisms of obesity-induced vitamin D regulation.

scholarly journals Assessing the impact of a mushroom-derived food ingredient on vitamin D levels in healthy volunteers

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Jorge Marques Pinto ◽  
Viviane Merzbach ◽  
Ashley G. B. Willmott ◽  
Jose Antonio ◽  
Justin Roberts
Keyword(s):  
Vitamin D ◽  
Healthy Volunteers ◽  
Venous Blood ◽  
Vitamin D Insufficiency ◽  
Food Sources ◽  
Natural Food ◽  
Vitamin D Status ◽  
Food Ingredient ◽  
Vitamin D Levels ◽  
The Impact

Abstract Background Prevalence of vitamin D insufficiency/deficiency has been noted in athletic populations, although less is known about recreationally active individuals. Biofortification of natural food sources (e.g. UV radiated mushrooms) may support vitamin D status and is therefore of current scientific and commercial interest. The aim of this study was to assess the impact of a mushroom-derived food ingredient on vitamin D status in recreationally active, healthy volunteers. Methods Twenty-eight participants were randomly assigned to either: 25 μg (1000 IU) encapsulated natural mushroom-derived vitamin D2; matched-dose encapsulated vitamin D3 or placebo (PL) for 12 weeks. Venous blood samples were collected at baseline, week 6 and 12 for analysis of serum 25(OH)D2 and 25(OH)D3 using liquid chromatography mass spectrometry. Habitual dietary intake and activity were monitored across the intervention. Results Vitamin D status (25(OH)DTOTAL) was significantly increased with vitamin D3 supplementation from 46.1 ± 5.3 nmol·L− 1 to 88.0 ± 8.6 nmol·L− 1 (p < 0.0001) across the intervention, coupled with an expected rise in 25(OH)D3 concentrations from 38.8 ± 5.2 nmol·L− 1 to 82.0 ± 7.9 nmol·L− 1 (p < 0.0001). In contrast, D2 supplementation increased 25(OH)D2 by + 347% (7.0 ± 1.1 nmol·L− 1 to 31.4 ± 2.1 nmol·L− 1, p < 0.0001), but resulted in a − 42% reduction in 25(OH)D3 by week 6 (p = 0.001). A net + 14% increase in 25(OH)DTOTAL was established with D2 supplementation by week 12 (p > 0.05), which was not statistically different to D3. Vitamin D status was maintained with PL, following an initial − 15% reduction by week 6 (p ≤ 0.046 compared to both supplement groups). Conclusions The use of a UV radiated mushroom food ingredient was effective in maintaining 25(OH)DTOTAL in healthy, recreationally active volunteers. This may offer an adjunct strategy in supporting vitamin D intake. However, consistent with the literature, the use of vitamin D3 supplementation likely offers benefits when acute elevation in vitamin D status is warranted.

scholarly journals Oral vitamin D supplementation has a lower bioavailability and reduces hypersecretion of parathyroid hormone and insulin resistance in obese Chinese males

2014 ◽  
Vol 18 (12) ◽  
pp. 2211-2219 ◽  
Author(s):  
Ji-Chang Zhou ◽  
Yu-Mei Zhu ◽  
Zheng Chen ◽  
Jun-Luan Mo ◽  
Feng-Zhu Xie ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Vitamin D ◽  
Parathyroid Hormone ◽  
Vitamin D Supplementation ◽  
Normal Weight ◽  
Vitamin D Status ◽  
Intervention Trial ◽  
Oral Vitamin ◽  
Hydroxyvitamin D ◽  
25 Hydroxyvitamin D

AbstractObjectiveTo examine the vitamin D status, SNP of the vitamin D receptor gene (VDR) and the effects of vitamin D supplementation on parathyroid hormone and insulin secretion in adult males with obesity or normal weight in a subtropical Chinese city.DesignAn intervention trial.SettingShenzhen City, Guangdong Province, China.SubjectsFrom a cross-sectional survey conducted from June to July, eighty-two normal-weight and ninety-nine obese males (18–69 years) were screened to analyse their vitamin D status and for five SNP of VDR. From these individuals, in the same season of a different year, obese and normal-weight male volunteers (twenty-one per group) were included for an intervention trial with oral vitamin D supplementation at 1250 µg/week for 8 weeks.ResultsFor the survey, there was no significant difference (P>0·05) in baseline circulating 25-hydroxyvitamin D concentrations or in the percentages of participants in different categories of vitamin D status between the two groups. The VDR SNP, rs3782905, was significantly associated with obesity (P=0·043), but none of the examined SNP were correlated with serum 25-hydroxyvitamin D when adjusted for age, BMI and study group. After vitamin D supplementation, serum 25-hydroxyvitamin D concentration, hypersecretions of parathyroid hormone and insulin, and insulin resistance in the obese were changed beneficially (P<0·05); however, the increase in serum 25-hydroxyvitamin D was less than that of the normal-weight men.ConclusionsFor obese and normal-weight men of subtropical China, the summer baseline vitamin D status was similar. However, oral vitamin D supplementation revealed a decreased bioavailability of vitamin D in obese men and ameliorated their hypersecretion of parathyroid hormone and insulin resistance.

scholarly journals Vitamin D in the Prevention and Treatment of Osteoarthritis: From Clinical Interventions to Cellular Evidence

Nutrients ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 243 ◽  
Author(s):  
Clara Yongjoo Park
Keyword(s):  
Vitamin D ◽  
Observational Studies ◽  
Pilot Trial ◽  
Clinical Results ◽  
Vitamin D Supplementation ◽  
Vitamin D Status ◽  
Randomized Controlled ◽  
The Relationship

Older adults are recommended vitamin D to prevent fractures. Though this population is also at risk of osteoarthritis (OA), the effect of vitamin D on OA is unclear and may differ by disease state. The relationship between vitamin D and OA during OA initiation and progression were considered in this narrative review of in vivo and in vitro studies. Regarding OA initiation in humans, the small number of published observational studies suggest a lack of association between induction of OA and vitamin D status. Most randomized controlled trials were performed in White OA patients with relatively high vitamin D status (>50 nmol/L). These studies found no benefit of vitamin D supplementation on OA progression. However, subset analyses and one randomized controlled pilot trial indicated that vitamin D supplementation may alleviate joint pain in OA patients with low vitamin D status (<50 nmol/L). As the etiology of OA is recently being more fully uncovered, better animal and cell models are needed. According to currently available clinical results, evidence is lacking to set a vitamin D level to prevent OA, and increasing vitamin D status above 50 nmol/L does not seem to benefit OA patients.

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