Observational studies have demonstrated an association between decreased vitamin D level and risk of multiple sclerosis (MS); however, it remains unclear whether this relationship is causal. We undertook a Mendelian randomization (MR) study to evaluate whether genetically lowered vitamin D level influences the risk of MS.
There is intense interest in identifying modifiable risk factors associated with autism-spectrum disorders (ASD). Autism-related traits, which can be assessed in a continuous fashion, share risk factors with ASD, and thus can serve as informative phenotypes in population-based cohort studies. Based on the growing body of research linking gestational vitamin D deficiency with altered brain development, this common exposure is a candidate modifiable risk factor for ASD and autism-related traits. The association between gestational vitamin D deficiency and a continuous measure of autism-related traits at ~6 years (Social Responsiveness Scale; SRS) was determined in a large population-based cohort of mothers and their children (n=4229). 25-hydroxyvitamin D (25OHD) was assessed from maternal mid-gestation sera and from neonatal sera (collected from cord blood). Vitamin D deficiency was defined as 25OHD concentrations less than 25 nmol l(-1). Compared with the 25OHD sufficient group (25OHD>50 nmol l(-1)), those who were 25OHD deficient had significantly higher (more abnormal) SRS scores (mid-gestation n=2866, β=0.06, P<0.001; cord blood n=1712, β=0.03, P=0.01). The findings persisted (a) when we restricted the models to offspring with European ancestry, (b) when we adjusted for sample structure using genetic data, (c) when 25OHD was entered as a continuous measure in the models and (d) when we corrected for the effect of season of blood sampling. Gestational vitamin D deficiency was associated with autism-related traits in a large population-based sample. Because gestational vitamin D deficiency is readily preventable with safe, cheap and accessible supplements, this candidate risk factor warrants closer scrutiny.Molecular Psychiatry advance online publication, 29 November 2016; doi:10.1038/mp.2016.213.
Obesity is associated with vitamin D deficiency, and both are areas of active public health concern. We explored the causality and direction of the relationship between body mass index (BMI) and 25-hydroxyvitamin D [25(OH)D] using genetic markers as instrumental variables (IVs) in bi-directional Mendelian randomization (MR) analysis.
Considering that epidemiological studies show that suicide rates in many countries are highest in the spring when vitamin D status is lowest, and that low vitamin D status can affect brain function, we sought to evaluate if a low level of 25-hydroxyvitamin D [25(OH)D] could be a predisposing factor for suicide.
Over the past few decades, food fortification and infant formula supplementation with high levels of vitamins have led to a sharp increase in vitamin intake among infants, children and adults. This is followed by a sharp increase in the prevalence of obesity and related diseases, with significant disparities among countries and different groups within a country. It has long been known that B vitamins at doses below their toxicity threshold strongly promote body fat gain. Studies have demonstrated that formulas, which have very high levels of vitamins, significantly promote infant weight gain, especially fat mass gain, a known risk factor for children developing obesity. Furthermore, ecological studies have shown that increased B vitamin consumption is strongly correlated with the prevalence of obesity and diabetes. We therefore hypothesize that excess vitamins may play a causal role in the increased prevalence of obesity. This review will discuss: (1) the causes of increased vitamin intake; (2) the non-monotonic effect of excess vitamin intake on weight and fat gain; and (3) the role of vitamin fortification in obesity disparities among countries and different groups within a country.
Vitamin D Deficiency Is a Risk Factor for Infections in Patients Affected by HCV-Related Liver Cirrhosis
- International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases
- Published almost 2 years ago
To evaluate the prevalence of vitamin D deficiency and its impact on infections in HCV-related liver cirrhosis.
Very few studies have investigated the determinants of circulating 25-hydroxyvitamin D (25[OH]D) in young adults (18-25 years old) using a set of variables that include lifestyle, sociodemographic, and anthropometric data. Our aim was to investigate the association between these variables and vitamin D status in a sample of untreated young adults.
Vitamin D deficiency has been linked to an increased risk of osteoporosis. Vitamin D deficiency has reached high levels in the Saudi population, but there is conflicting evidence both in the Saudi population, and worldwide, regarding the existence of a correlation between these low vitamin D levels and reduced BMD (bone mineral density), or osteoporosis.
Vitamin D deficiency is prevalent worldwide, but some groups are at greater risk. We aim to evaluate vitamin D levels in different occupations and identify groups vulnerable to vitamin D deficiency.
- The Journal of the American Osteopathic Association
- Published about 2 years ago
Vitamin D deficiency has been identified as a common metabolic/endocrine abnormality. Despite known dietary sources of vitamin D and the role of sunlight in its production, much of the US population may have inadequate levels of serum 25-hydroxyvitamin D. Deficiency of vitamin D can be caused by a variety of health conditions, but studies on the effects of vitamin D supplements have had mixed results. This evidence-based clinical review discusses what is currently known about vitamin D and what areas need further research to clarify its role in health and disease.