ArticlePloS one2013
Make vitamin D while the sun shines, take supplements when it doesn't: a longitudinal, observational study of older adults in Tasmania, Australia.
Article in PloS one, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 19 papers, 1 of them a synthesis that pooled it.
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Who cites it
19 citing papers in PubMed, 1 synthesis or guideline pooled it, 43 citations in OpenAlex.
- Relationship between vitamin D levels and pediatric celiac disease: a systematic review and meta-analysis.BMC pediatrics · 2024Pooled it
- Results of longitudinal Nutri-D study: factors influencing winter and summer vitamin D status in a Caucasian population.Frontiers in nutrition · 2023Article
- Seasonal Changes in Vitamin D Levels of Healthy Children in Mid-Latitude, Asian Urban Area.Pediatric gastroenterology, hepatology & nutrition · 2021Article
- Adequate Vitamin D Intake Cannot Be Achieved within Carbon Emission Limits Unless Food Is Fortified: A Simulation Study.Nutrients · 2021Article
- Suboptimal Serum 25-Hydroxy-Vitamin D Is Associated with a History of Recent Disease Exacerbation in Pediatric Patients with Bronchial Asthma or Asthma-Suggestive Recurrent Wheezing.International journal of environmental research and public health · 2020Article
- Vitamin D Status and Correlation with Glucose and Lipid Metabolism in Gansu Province, China.Diabetes, metabolic syndrome and obesity : targets and therapy · 2020Article
- Developmental Vitamin D Deficiency in the Rat Impairs Recognition Memory, but Has No Effect on Social Approach or Hedonia.Nutrients · 2019Article
- Effect of vitamin D status on normal fertilization rate following in vitro fertilization.Reproductive biology and endocrinology : RB&E · 2019Article
- Seasonal temperature is associated with Parkinson's disease prescriptions: an ecological study.International journal of biometeorology · 2017Article
- Winter to summer change in vitamin D status reduces systemic inflammation and bioenergetic activity of human peripheral blood mononuclear cells.Redox biology · 2017Article
- Vitamin D research and public health nutrition: a current perspective.Public health nutrition · 2017Article
- The Hidden Function of Vitamin D.Open access Macedonian journal of medical sciences · 2016Article
- Seasonal Epidemiology of Serum 25-Hydroxyvitamin D Concentrations among Healthy Adults Living in Rural and Urban Areas in Mongolia.Nutrients · 2016Article
- Seasons in the sun: the impact on IVF results one month later.Facts, views & vision in ObGyn · 2016Article
- High Prevalence of Vitamin D Deficiency in Infertile Women Referring for Assisted Reproduction.Nutrients · 2015Article
- Vitamin D status and its association with season, hospital and sepsis mortality in critical illness.Critical care (London, England) · 2014Observational
- Age-related changes in physical fall risk factors: results from a 3 year follow-up of community dwelling older adults in Tasmania, Australia.International journal of environmental research and public health · 2013Article
- Vitamin D and immune function.Nutrients · 2013Review
- The Association between Seasonal Variation in Vitamin D, Postural Sway, and Falls Risk: An Observational Cohort Study.Journal of aging research · 2013Article
Corrections and comments
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Authors and funding
6 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Low vitamin D status has been associated with a number of chronic conditions, particularly in older adults. The aim of this study was to identify how best to maintain optimum vitamin D status throughout the year in this high-risk population. The main objectives of the study were to assess seasonal vitamin D status; identify the main determinants of vitamin D status; determine if taking part in the study led to alterations in participant behaviour and vitamin D status. A longitudinal design across four consecutive seasons observed ninety-one 60-85 year old community-dwelling adults in Tasmania (41π S) over 13 consecutive months, with a follow-up assessment at next winter's end. Associations between solar UVB exposure, sun protection behaviours, dietary and supplemental vitamin D with serum 25(OH)D concentrations were assessed. Variation in serum 25(OH)D demonstrated an identical pattern to solar UVB, lagging 8-10 weeks. Serum 25(OH)D was positively associated with summer UVB (mean 15.9 nmol/L; 95%CI 11.8-19.9 nmol/L, p<0.001) and vitamin D supplementation (100-600 IU/day: 95%CI 10.2 nmol/L; 0.8-19.6 nmol/L; p = 0.03; 800 IU/day: 21.0 nmol/L; 95%CI 8.1-34.0 nmol/L; p = 0.001). Seasonal variation in serum 25(OH)D was greatly diminished in supplement users. The most common alteration in participant behaviour after the study was ingesting vitamin D supplements. Post-study vitamin D supplementation ℘800 IU/day was seven times more likely than during the study resulting in mean difference in serum 25(OH)D between supplement and non-supplement users of 30.1 nmol/L (95%CI 19.4-40.8 nmol/L; p<0.001). The main limitation was homogeneity of participant ethnicity. Solar exposure in summer and ingestion of vitamin D supplements in other seasons are the most effective ways of achieving and maintaining year-round vitamin D sufficiency in older adults in the Southern hemisphere. Vitamin D supplementation has greatest effect on vitamin D status if ingested during and after winter, i.e. between the autumn and spring equinoxes.
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