Should We Be Concerned about the Vitamin D Status of Athletes?

2008 ◽  
Vol 18 (2) ◽  
pp. 204-224 ◽  
Author(s):  
Kentz S. Willis ◽  
Nikki J. Peterson ◽  
D. Enette Larson-Meyer
Keyword(s):  
Vitamin D ◽  
Bone Health ◽  
Skin Pigmentation ◽  
Sun Exposure ◽  
The Elderly ◽  
Vitamin D Insufficiency ◽  
Vitamin D Status ◽  
High Prevalence ◽  
The Hours ◽  
Human Immunity

A surprisingly high prevalence of vitamin D insufficiency and deficiency has recently been reported worldwide. Although very little is known about vitamin D status among athletes, a few studies suggest that poor vitamin D status is also a problem in athletic populations. It is well recognized that vitamin D is necessary for optimal bone health, but emerging evidence is finding that vitamin D deficiency increases the risk of autoimmune diseases and nonskeletal chronic diseases and can also have a profound effect on human immunity, inflammation, and muscle function (in the elderly). Thus, it is likely that compromised vitamin D status can affect an athlete’s overall health and ability to train (i.e., by affecting bone health, innate immunity, and exercise-related immunity and inflammation). Although further research in this area is needed, it is important that sports nutritionists assess vitamin D (as well as calcium) intake and make appropriate recommendations that will help athletes achieve adequate vitamin D status: serum 25(OH)D of at least 75 or 80 nmol/L. These recommendations can include regular safe sun exposure (twice a week between the hours of 10 a.m. and 3 p.m. on the arms and legs for 5–30 min, depending on season, latitude, and skin pigmentation) or dietary supplementation with 1,000–2,000 IU vitamin D3 per day. Although this is significantly higher than what is currently considered the adequate intake, recent research demonstrates these levels to be safe and possibly necessary to maintain adequate 25(OH)D concentrations.

scholarly journals Nutrihealth Study: Seasonal Variation in Vitamin D Status Among the Slovenian Adult and Elderly Population

Nutrients ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1838 ◽  
Author(s):  
Maša Hribar ◽  
Hristo Hristov ◽  
Matej Gregorič ◽  
Urška Blaznik ◽  
Katja Zaletel ◽  
...  
Keyword(s):  
Vitamin D ◽  
Seasonal Variation ◽  
Vitamin D Deficiency ◽  
Elderly Population ◽  
Sun Exposure ◽  
Epidemiological Data ◽  
The Elderly ◽  
Vitamin D Insufficiency ◽  
Ultraviolet B ◽  
Vitamin D Status

Several studies conducted around the world showed substantial vitamin D insufficiency and deficiency among different population groups. Sources of vitamin D in the human body include ultraviolet B (UVB)-light-induced biosynthesis and dietary intake, but people’s diets are often poor in vitamin D. Furthermore, in many regions, sun exposure and the intensity of UVB irradiation during wintertime are not sufficient for vitamin D biosynthesis. In Slovenia, epidemiological data about vitamin D status in the population were investigated through a national Nutrihealth study—an extension to the national dietary survey SI.Menu (2017/18). The study was conducted on a representative sample of 125 adult (18–64 years) and 155 elderly (65–74 years old) subjects, enrolled in the study in different seasons. Their vitamin D status was determined by measuring the serum 25-hydroxy-vitamin D (25(OH)D) concentration. Thresholds for vitamin D deficiency and insufficiency were 25(OH)D levels below 30 and 50 nmol/L, respectively. Altogether, 24.9% of the adults and 23.5% of the elderly were found to be vitamin D deficient, while an insufficient status was found in 58.2% and 62.9%, respectively. A particularly concerning situation was observed during extended wintertime (November–April); vitamin D deficiency was found in 40.8% and 34.6%, and insufficient serum 25(OH)D levels were observed in 81.6% and 78.8%, respectively. The results of the study showed high seasonal variation in serum 25(OH)D levels in both the adult and elderly population, with deficiency being especially pronounced during wintertime. The prevalence of this deficiency in Slovenia is among the highest in Europe and poses a possible public health risk that needs to be addressed with appropriate recommendations and/or policy interventions.

scholarly journals Sun exposure, dressing habits, and vitamin D status in Morocco

2021 ◽  
Vol 319 ◽  
pp. 01097
Author(s):  
Sakhr Dadda ◽  
Karima Azekour ◽  
Fouzia Sebbari ◽  
Brahim El Houate ◽  
Bachir El Bouhali
Keyword(s):  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Sun Exposure ◽  
Vitamin D Insufficiency ◽  
Activity Level ◽  
Vitamin D Status ◽  
Vitamin D Levels ◽  
High Prevalence ◽  
Daily Sunshine ◽  
Local Healthcare

Sunlight is the main source of vitamin D. Almost 80% of vitamin D3 is produced in the skin. The region of Draa Tafilalet benefits from long daily sunshine time. As such, vitamin D deficiency should be low in this region. However, dressing habits can highly influence vitamin D status. This study aimed to evaluate sun exposure and its relation to vitamin D status among the general population in the region of Draa-Tafilalet, Morocco. Clinical, biological, and sociodemographic data were obtained from 331 adults visiting local healthcare units during the summers of 2019 and 2020. Plasma 25(OH)D2/D3 was measured by immunofluorescence. The prevalence of vitamin D deficiency was 37.5%, while Vitamin D insufficiency represented 56.5%. Most of the studied population (76.4%) had restricting dressing habits and exposed only their faces. statistic tests showed a correlation of vitamin D levels with daily sun exposure (r= 0.308, p<0.001), dressing habits (p<0.001), age (r= -0.141, p=0.01), sex (p<0.001), physical activity level (p=0.003), and BMI (r= -0.298, p<0.001). The study showed a high prevalence of vitamin D deficiency in this region. Similarly, it exposed the effects of restricting clothes and low daily sun exposure on vitamin D status.

Validation of Brief Questionnaire Measures of Sun Exposure and Skin Pigmentation Against Detailed and Objective Measures Including Vitamin D Status

2012 ◽  
Vol 89 (1) ◽  
pp. 219-226 ◽  
Author(s):  
Jessica Cargill ◽  
Robyn M. Lucas ◽  
Peter Gies ◽  
Kerryn King ◽  
Ashwin Swaminathan ◽  
...  
Keyword(s):  
Vitamin D ◽  
Skin Pigmentation ◽  
Sun Exposure ◽  
Objective Measures ◽  
Vitamin D Status ◽  
Questionnaire Measures

Vitamin D Status and Muscle Function Among Adolescent and Young Swimmers

2017 ◽  
Vol 27 (5) ◽  
pp. 399-407 ◽  
Author(s):  
Nina Rica Wium Geiker ◽  
Mette Hansen ◽  
Jette Jakobsen ◽  
Michael Kristensen ◽  
Rikke Larsen ◽  
...  
Keyword(s):  
Vitamin D ◽  
Muscle Strength ◽  
Grip Strength ◽  
Muscle Function ◽  
Sun Exposure ◽  
Vitamin D Insufficiency ◽  
Vitamin D Status ◽  
Hand Grip ◽  
Elite Swimmers ◽  
Sufficient Vitamin

Impaired muscle function has been coupled to vitamin D insufficiency in young women and in elderly men and women. Those living at Northern latitudes are at risk for vitamin D insufficiency due to low sun exposure which may be more pronounced among elite swimmers because of their indoor training schedules. We aimed to examine vitamin D status among young elite swimmers and evaluate the association between vitamin D status and muscle strength. Twenty-nine swimmers, 12 female and 17 male (16–24 years) residing at latitude 55–56°N were studied in March and April. Blood samples were analyzed for serum 25-hydroxyvitamin D (s-25(OH)D) and hand-grip strength was measured as marker of muscle strength. Subjects´ vitamin D and calcium intake were assessed by food frequency questionnaire and sun exposure and training status by questionnaires. Mean (± SD) s-25(OH)D was 52.6 ± 18.3nmol/L among all swimmers. In 45% of the swimmers s-25(OH)D was below 50 nmol/L. Female swimmers had higher s-25(OH)D concentration than male swimmers (61.7 ± 17,5 nmol/L vs. 46.2 ± 16,5 nmol/L, p = .026). Among male swimmers, those with sufficient vitamin D status had higher hand grip strength than those with insufficient vitamin D status (50.6 ± 6.4 kg vs. 41.1 ± 7.8 kg, p = .02). Among Danish elite swimmers 45% had an insufficient vitamin D status during the spring; the prevalence being higher among male swimmers. Muscle strength was significantly higher in male swimmers with sufficient vitamin D status.

Vitamin D Status and Supplementation in Elite Irish Athletes

2013 ◽  
Vol 23 (5) ◽  
pp. 441-448 ◽  
Author(s):  
Pamela J. Magee ◽  
L. Kirsty Pourshahidi ◽  
Julie M. W. Wallace ◽  
John Cleary ◽  
Joe Conway ◽  
...  
Keyword(s):  
Vitamin D ◽  
Biochemical Analysis ◽  
Vitamin D Insufficiency ◽  
Early Spring ◽  
Vitamin D Status ◽  
Hydroxyvitamin D ◽  
High Prevalence ◽  
25 Hydroxyvitamin D ◽  
And Training ◽  
Vitamin D Supplement

Background:A high prevalence of vitamin D insufficiency/deficiency, which may impact on health and training ability, is evident among athletes worldwide. This observational study investigated the vitamin D status of elite Irish athletes and determined the effect of wintertime supplementation on status.Methods:Serum 25-hydroxyvitamin D [25(OH)D], calcium, and plasma parathyroid hormone were analyzed in elite athletes in November 2010 (17 boxers, 33 paralympians) or March 2011 (34 Gaelic Athletic Association [GAA] players). A subset of boxers and paralympians (n = 27) were supplemented during the winter months with either 5,000 IU vitamin D3/d for 10–12 weeks or 50,000 IU on one or two occasions. Biochemical analysis was repeated following supplementation.Results:Median 25(OH)D of all athletes at baseline was 48.4 nmol/L. Vitamin D insufficiency/deficiency (serum 25(OH)D <50 nmol/L) was particularly evident among GAA players (94%) due to month of sampling. Wintertime supplementation (all doses) significantly increased 25(OH)D (median 62.8 nmol/L at baseline vs. 71.1 nmol/L in April or May; p = .001) and corrected any insufficiencies/deficiencies in this subset of athletes. In contrast, 25(OH)D significantly decreased in those that did not receive a vitamin D supplement, with 74% of athletes classed as vitamin D insufficient/deficient after winter, compared with only 35% at baseline.Conclusions:This study has highlighted a high prevalence of vitamin D insufficiency/deficiency among elite Irish athletes and demonstrated that wintertime vitamin D3 supplementation is an appropriate regimen to ensure vitamin D sufficiency in athletes during winter and early spring.

Frequency of Combined Deficiencies of Vitamin D and Holotranscobalamin in Cancer Patients.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3674-3674
Author(s):  
Ashley S. Plant ◽  
Glenn Tisman
Keyword(s):  
Vitamin D ◽  
Vitamin B12 ◽  
Cancer Patients ◽  
Sun Exposure ◽  
Serum Levels ◽  
The Elderly ◽  
Vitamin D Insufficiency ◽  
Total Serum ◽  
Low Levels ◽  
Low Serum

Abstract Low serum levels of vitamin D are associated with a higher frequency of at least eleven different malignancies including breast, colon, and prostate cancer (Holick, M.F. Vitamin D: Millenium Perspective. Journal of Cellular Biochemistry. 2003. 88:296–307). Low levels of vitamin B12 were found to contribute to a 2.5–4.0 times greater likelihood of breast cancer in postmenopausal women (Wu, K. et al. Cancer Epidemiol. 1999. 8:209–17) and hematological and mucosal tissue is more sensitive to chemotherapy in the presence of insufficient levels of B12. Only vitamin B12 that is complexed to transcobalamin as holotranscobalamin (HTCII) is metabolically active. It has been suggested that decreased HTCII serum levels are involved in the failure to methylate DNA resulting in the activation of oncogenes that would normally be dormant (Herbert, V. Methyl Metabolism: Epigenetics, Genomics, Proteomics. 2002 FASEB Summer Research Conference. Snowmass Village, Colarado.).Our study investigated vitamin D, total B12 and HTCII levels in 70 cancer patients. Vitamin D was measured as serum 25 OH-D3 (Nichols Advantage assay) and serum B12 was measured as both total B12 and as the metabolically active HTCII (Immulite B12 assay followed by glass adsorption: Vu, T. et al., Am J. Heme42: 202–211 1993). Vitamin D insufficiency has been defined based on differing physiologic sequelae of insufficiency and varies between values less than 50–75 nMol/L. When vitamin D insufficiency is defined as serum level <75nmol/L, 43 of 60 (72%) of cancer patients were found to be insufficient. At a lower definition of insufficiency, <50nmol/L, 24 of 60 patients (40%) were insufficient. Of 52 patients, only 3 (6%) were found to have insufficient serum levels of total B12 (normal >300pg/mL) while 17 of 52 (34%) were found to be HTCII insufficient (normal >69 pg/mL). Of these 17 patients, 14 (84.4%) had normal total B12 levels. Low levels of vitamin D strongly correlated with low serum HTCII. All 12 HTCII deficient patients were vitamin D insufficient at the <75nmol/L standard. Six of 12 HTCII deficient patients (50%) were vitamin D deficient at the <50nmol/L cut off. Chi-squared test for independence revealed a strong relationship between low levels of vitamin D and HTCII. Deficiency of vitamin D (70%) and holotranscobalamin (34%) is prevalent among newly diagnosed patients with cancer. The standard measurement of total serum B12 alone is inadequate for identifying patients with insufficient levels of metabolically active B12. Low vitamin D and holotranscobalamin levels may play a role in cancer development, progression and host response to tumor and therapy. Possible explanations for combined HTCII and D3 deficiency include age, the presence of atrophic gastritis in 30–50% of the elderly, and lack of sun exposure and deficient production of D3 in the elderly. Since both vitamins are conserved by cubulin/megalin mediated renal tubular reabsorption a defect of this mechanism could contribute to deficiency of both vitamins. Study supported in part by ThinkTwice Technologies. This work is dedicated to the memory of Dr. Victor Herbert whose teachings continue to inspire our research efforts.

scholarly journals Vitamin D and bone health in early life

2003 ◽  
Vol 62 (4) ◽  
pp. 823-828 ◽  
Author(s):  
Christian Mølgaard ◽  
Kim Fleischer Michaelsen
Keyword(s):  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Age Distribution ◽  
High Capacity ◽  
Growth Failure ◽  
Sun Exposure ◽  
Vitamin D Insufficiency ◽  
Vitamin D Supplementation ◽  
Vitamin D Status ◽  
Increased Risk

Prolonged vitamin D deficiency resulting in rickets is seen mainly during rapid growth. A distinct age distribution has been observed in the Copenhagen area where all registered hospital cases of rickets were either infants and toddlers or adolescents from immigrant families. Growth retardation was only present in the infant and toddler group. A state of deficiency occurs months before rickets is obvious on physical examination. Growth failure, lethargy and irritability may be early signs of vitamin D deficiency. Mothers with low vitamin D status give birth to children with low vitamin D status and increased risk of rickets. Reports showing increasing rates of rickets due to insufficient sunlight exposure and inadequate vitamin D intake are cause for serious concern. Many countries (including the USA from 2003) recommend vitamin D supplementation during infancy to avoid rickets resulting from the low vitamin D content of human milk. Without fortification only certain foods such as fatty fish contain more than low amounts of vitamin D, and many children will depend entirely on sun exposure to obtain sufficient vitamin D. The skin has a high capacity to synthesize vitamin D, but if sun exposure is low vitamin D production is insufficient, especially in dark-skinned infants. The use of serum 25-hydroxyvitamin D to evaluate vitamin D status before development of rickets would be helpful; however, there is no agreement on cut-off levels for deficiency and insufficiency. Furthermore, it is not known how marginal vitamin D insufficiency affects children's bones in the long term.

scholarly journals OPTIMIZING VITAMIN D LEVELS IN PATIENTS WITH MULTIPLE SCLEROSIS

2008 ◽  
Vol 31 (4) ◽  
pp. 1
Author(s):  
P S Ahluwalia ◽  
L M Metz ◽  
D A Hanley
Keyword(s):  
Multiple Sclerosis ◽  
Vitamin D ◽  
Serum Level ◽  
Graduate Student ◽  
Bone Health ◽  
Vitamin D Insufficiency ◽  
Baseline Serum ◽  
Vitamin D Levels ◽  
High Prevalence ◽  
Insight Into

Background: Emerging research suggests that vitamin D plays animportant role beyond bone health, particularly in immune function and may beimportant in people with Multiple Sclerosis (MS). MS clinic physicians in Calgary, Alberta believe that patients should have at least minimallysufficient ( > 80nmol/L) serum 25(OH)D levels to maintain adequate bone health. Involving patients in the assessment and management of their ownvitamin D needs may be effective and more efficient than having clinicians track levels. Objectives: Determine the prevalence of vitamin D insufficiency and the feasibility of using different management methods to optimize serum25(OH)D levels. Methods: 213 patients who attended the Calgary MS Clinicbetween September 2006 and January 2007 participated in this study. Eachpatient agreed to have serum 25(OH)D levels measured, and to adjust theirvitamin D dose according to an algorithm that they would follow or that would be used by a graduate student to recommend dose changes at baseline, 3- and 6-months. Results: Mean age was 45.6 years (range 21-72); 78.9% werewomen. Mean EDSS was 3.2 (range 0-8.5). Mean baseline serum level was 72.8nmol/L (SD 26.8) (range 17.9-160.0); 62.4% had levels < 80 nmol/L. 60.6% of subjects were taking at least 1000 IU. Conclusions: We found a high prevalence of vitamin D insufficiency despite a sizeable proportion taking at least 1000 IU of vitamin D3 daily. Six month data, including adherence to the study protocol and proportion ofparticipants with optimized 25(OH)D levels will be presented. Insight into themanagement of dosing for patients could have an impact on the integration ofvitamin D optimization into the MS population.

scholarly journals High latitude and marine diet: vitamin D status in elderly Faroese

2010 ◽  
Vol 104 (6) ◽  
pp. 914-918 ◽  
Author(s):  
Christine Dalgård ◽  
Maria Skaalum Petersen ◽  
Anne V. Schmedes ◽  
Ivan Brandslund ◽  
Pal Weihe ◽  
...  
Keyword(s):  
Vitamin D ◽  
Human Subjects ◽  
Sun Exposure ◽  
The Elderly ◽  
Vitamin D Status ◽  
High Intake ◽  
Cross Sectional ◽  
Pilot Whale ◽  
Vitamin D Levels ◽  
Marine Food

Human subjects obtain their vitamin D from the diet, especially from marine food, and from endogenous synthesis following cutaneous sun exposure. The risk of an insufficient vitamin D synthesis is increased in northern populations, but it may be counteracted by a high intake of marine food in fishing populations, e.g. at the Faroe Islands. We examined the vitamin D status and its statistical determinants in a cross-sectional study of 713 elderly Faroese aged 70–74 years, about two-thirds of all the eligible residents in this age group. Clinical examination included measurement of body weight and height, and marine food intake was estimated using a questionnaire. We measured serum 25-hydroxyvitamin D3 (S-25(OH)D3) by LC-MS/MS in 669 of the 713 subjects in whom sufficient serum was available. Of the population, 19 % had S-25(OH)D3 concentrations < 25 nmol/l, and only 10·3 % of the population had S-25(OH)D3 concentrations >80 nmol/l. In a logistic regression analysis, BMI < 30 kg/m2, blood sampling in summer season, eating pilot whale blubber more than once per month and female sex were positively associated with vitamin D levels >80 nmol/l. The high prevalence of low vitamin D levels among the elderly Faroese population reflects the low skin synthesis during most months of the year, which is caused by the limited sun exposure and insufficient benefits from marine diet. Thus, even in a population with a high intake of marine food, the northern latitude causes a low vitamin D status. Efforts to improve vitamin D status in this population are warranted.

ASSESSING THE RELATIONSHIP BETWEEN VITAMIN D STATUS AND IMPAIRMENTS IN COGNITIVE AND PHYSICAL PERFORMANCE IN OLDER ADULTS USING A DUAL TASK PHYSICAL PERFORMANCE TEST

2016 ◽  
pp. 1-8
Author(s):  
J. Lopez ◽  
A. Campa ◽  
J.E. Lewis ◽  
F.G. Huffman ◽  
J.P. Liuzzi ◽  
...  
Keyword(s):  
Vitamin D ◽  
Physical Performance ◽  
Dual Task ◽  
Performance Test ◽  
Executive Dysfunction ◽  
The Elderly ◽  
Vitamin D Insufficiency ◽  
Gait Velocity ◽  
Vitamin D Status ◽  
The Relationship

Background: Vitamin D deficiency has been associated with an increased risk of falls in older adults. Several studies have demonstrated an association between vitamin D deficiency and gait and cognitive impairments, which are two risk factors for falls in the elderly. There is lack of research about the role of vitamin D in cognitive function in the context of mobility. Objective: The purpose of this study was to evaluate the association between vitamin D status with the age-related changes in mobility through higher order cognitive function using a dual task physical performance test. Design: Cross-sectional Setting: Community-dwelling older adult population located in Miami, Fl. Participants: Healthy participants over the age of 55 (n=97) who participated in the parent interventional study. Measurements: Participants completed assessments that included serum levels of vitamin D, surveys, and dual task physical performance tests. Spearman’s correlations, independent t-tests, repeated measures ANOVAs and multiple logistic regressions were used to examine the relationship between vitamin D insufficiency (25-hydroxyvitamin D <30 ng/ml) and sufficiency (≥30 ng/ml) and dual task physical performance variables. The significance level was set at α=0.05. Results: There were no significant associations between vitamin D insufficiency and gait velocity during either task. Using Spearman correlations, slower single (P=0.011) and dual task counting rates (P=0.006) were significantly associated with vitamin D insufficiency. Independent t-tests showed dual and single task counting rates were significantly lower in the vitamin D insufficient group compared to the sufficient group (P=0.018 and P=0.028, respectively). The results for the ANOVAs indicated that velocities and counting rates were not significantly different by vitamin D status (Wilk’s Lambda =0.999; F (1, 95) =.11, P=.740) (Wilk’s Lambda =.999, F(1,95)=.13, P=.718). Vitamin D status was not significantly associated with dual task physical performance (defined as the difference in dual and single task) in gait velocity (OR=1.00, 95% CI: 0.98; 1.02, P=0.772) and counting rate (OR=1.684, 95% CI: 0.15; 19.57, P=0.677), when controlling for confounders. Conclusions: Since counting backward is a mental tracking task, which is a component of executive function, our results suggest a relationship between vitamin D insufficiency and executive dysfunction. Executive dysfunction has been previously associated with fall risks in the elderly, and it could be a possible mediator between vitamin D and falls. Our data suggest that cognition may play a significant role in vitamin D’s influence on falls, while motor function may play a lesser role.

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