• Leisure time computer use and adolescent bone health - findings from the Tromsø Study, Fit Futures: a cross sectional study 

      Winther, Anne; Ahmed, Luai Awad; Furberg, Anne-Sofie; Grimnes, Guri; Jorde, Rolf; Nilsen, Ole-Andreas; Dennison, Elaine; Emaus, Nina (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-03-20)
      <p>Objectives: Low levels of physical activity may have considerable negative effects on bone health in adolescence, and increasing screen time in place of sporting activity during growth is worrying. This study explored the associations between self-reported screen time at weekends and bone mineral density (BMD). <p>Design: In 2010/2011, 1038 (93%) of the region’s first-year upper-secondary ...
    • Longitudinal changes in vitamin D concentrations and the association with type 2 diabetes mellitus: the Tromsø Study 

      Allaoui, Giovanni; Rylander, Charlotta; Fuskevåg, Ole Martin; Averina, Maria; Wilsgaard, Tom; Brustad, Magritt; Jorde, Rolf; Berg, Vivian (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-02)
      Aim We aimed to investigate the relationship between pre- and post-diagnostic 25-hydroxyvitamin D (25(OH)D) concentrations and type 2 diabetes (T2DM) over a period of 30 years in individuals who developed T2DM compared to healthy controls.<p> <p>Methods This case–control study included 254 participants with blood samples collected at fve diferent time-points (T1–T5) between 1986 and 2016. Of the ...
    • Lost relation between blood pressure and serum 25-hydroxyvitamin D 

      Jorde, Rolf; Grimnes, Guri (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-12-26)
      Background: Low serum 25-hydroxyvitamin D (25(OH)D) levels have consistently been associated with hypertension. During the last decades there has been an unexplained reduction in blood pressure (BP) in Western countries. We therefore examined the relation between serum 25(OH)D and BP in the 7th survey of the Tromsø study 2015/2016.<p> <p>Methods: Blood pressure and serum 25(OH)D were measured and ...
    • No improvement in depressive symptoms by vitamin D supplementation: results from a randomised controlled trial 

      Jorde, Rolf; Kubiak, Julia Magdalena (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-11-22)
      In observational studies, vitamin D deficiency is associated with depressive symptoms. However, randomised controlled trials (RCT) with vitamin D supplementation have not been conclusive. In the present study 206 subjects were randomised to vitamin D (100 000 IU (2500 µg) as a bolus dose followed by 20 000 IU (500 µg) per week) and 202 to placebo. The Beck Depression Inventory-II (BDI-II) was filled ...
    • No improvement of sleep from vitamin D supplementation: insights from a randomized controlled trial 

      Larsen, Anette Uhlving; Hopstock, Laila Arnesdatter; Jorde, Rolf; Grimnes, Guri (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-19)
      <i><p>Background</i> Vitamin D has been linked to sleep health in observational studies. Data from randomized controlled trials (RCTs) with vitamin D is scarce. <i><p>Methods</i> This study presents the results of a secondary analysis of 189 vitamin D insufficient participants (47.1% women) in a previously performed RCT, of which 92 were randomized to vitamin D (100,000 IU (2500 μg) as a ...
    • No significant effect on bone mineral density by high doses of vitamin D-3 given to overweight subjects for one year 

      Jorde, Rolf; Sneve, Monica; Torjesen, Peter A; Figenschau, Yngve; Hansen, John-Bjarne; Grimnes, Guri (Journal article; Tidsskriftartikkel; Peer reviewed, 2010)
    • Non-skeletal health effects of Vitamin D supplementation: A systematic review on findings from meta-Analyses summarizing trial data 

      Rejnmark, Lars; Bislev, Lise Sofie; Cashman, Kevin D.; Eiríksdóttir, Gudny; Gaksch, Martin; Grübler, Martin; Grimnes, Guri; Gudnason, Vilmundur; Lips, Paul; Pilz, Stefan; Van Schoor, Natasja M.; Kiely, Mairead; Jorde, Rolf (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-07)
      Background:<br>A large number of observational studies have reported harmful effects of low 25-hydroxyvitamin D (25OHD) levels on non-skeletal outcomes. We performed a systematic quantitative review on characteristics of randomized clinical trials (RCTs) included in meta-analyses (MAs) on non-skeletal effects of vitamin D supplementation.<br>Methods and findings:<br>We identified systematic reviews ...
    • Persistent Organic Pollutants and the Association with Maternal and Infant Thyroid Homeostasis: A Multipollutant Assessment 

      Berg, Vivian; Nøst, Therese Haugdahl; Pettersen, Rolf Dagfinn; Hansen, Solrunn; Veyhe, Anna Sofia; Jorde, Rolf; Odland, Jon Øyvind; Sandanger, Torkjel M (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-01)
      Background:<br>Disruption of thyroid homeostasis has been indicated in human studies targeting effects of persistent organic pollutants (POPs). Influence on the maternal thyroid system by POPs is of special interest during pregnancy because such effects could impair infant thyroid homeostasis.<br> Objectives:<br>We investigated the association between POPs and thyroid-stimulating hormone (TSH) ...
    • The phosphodiesterase 8B gene rs4704397 is associated with thyroid function, risk of myocardial infarction and body height. The Tromsø Study 

      Jorde, Rolf; Schirmer, Henrik; Wilsgaard, Tom; Joakimsen, Ragnar Martin; Mathiesen, Ellisiv B.; Njølstad, Inger; Løchen, Maja-Lisa; Figenschau, Yngve Anton; Svartberg, Johan; Hutchinson, Moira Strand; Kjærgaard, Marie; Jørgensen, Lone; Grimnes, Guri (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      Objective: High serum thyrotropin (TSH) levels predict cardiovascular disease (CVD). Recently several single nucleotide polymorphisms (SNPs) associated with TSH levels have been identified, one of them being the rs4704397 SNP in the phosphodiesterase 8B (PDE8B) gene. If the relation between thyroid function and CVD is causal, one could also expect rs4704397 genotypes to predict CVD and possibly ...
    • Plasma profile of microRNA after supplementation with high doses of vitamin D3 for 12 months 

      Jorde, Rolf; Svartberg, Johan; Joakimsen, Ragnar Martin; Coucheron, Dag-Hugo (Journal article; Tidsskriftartikkel; Peer reviewed, 2012-05-17)
      Background: Recently a large number of short non-coding-RNAs (microRNAs, (miRNA)) have been identified. These miRNAs act as post-transcriptional regulators where they generally have an inhibitory function. miRNAs are present in all human cells, and they are also detected in serum or plasma. The miRNAs have a broad range of actions, and their biogenesis must therefore be under tight control. One ...
    • Polymorphisms in the vitamin D system and mortality - The Tromsø study 

      Jorde, Rolf; Wilsgaard, Tom; Grimnes, Guri (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-09-18)
      Vitamin D deficiency is associated with diabetes, cancer, immunological and cardiovascular diseases as well as increased mortality. It has, however, been difficult to show a causal relation in randomized, controlled trials. Mendelian randomization studies provide another option for testing causality, and results indicate relations between the serum 25-hydroxyvitamin D (25(OH)D) level and some diseases, ...
    • Polymorphisms Related to the Serum 25-Hydroxyvitamin D Level and Risk of Myocardial Infarction, Diabetes, Cancer and Mortality. The Tromsø Study 

      Jorde, Rolf; Schirmer, Henrik; Wilsgaard, Tom; Joakimsen, Ragnar Martin; Mathiesen, Ellisiv B.; Njølstad, Inger; Løchen, Maja-Lisa; Figenschau, Yngve; Berg, Jens Petter; Svartberg, Johan; Grimnes, Guri (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
      Low serum 25(OH)D levels are associated with cardiovascular risk factors, and also predict future myocardial infarction (MI), type 2 diabetes (T2DM), cancer and all-cause mortality. Recently several single nucleotide polymorphisms (SNPs) associated with serum 25-hydroxyvitamin D (25(OH)D) level have been identified. If these relations are causal one would expect a similar association between these ...
    • Rationale and plan for vitamin D food fortification: A review and guidance paper 

      Pilz, Stefan; März, Winfried; Cashman, Kevin D; Kiely, Mairead; Whiting, Susan J; Holick, Michael F.; Grant, William B; Pludowski, Pawel; Hiligsmann, Mickaël; Trummer, Christian; Schwetz, Verena; Lerchbaum, Elisabeth; Pandis, Marlene; Tomaschitz, Andreas; Grübler, Martin; Gaksch, Martin; Verheyen, Nicolas; Hollis, Bruce W; Rejnmark, Lars; Karras, Spyridon N.; Hahn, Andreas; Bischoff-Ferrari, Heike Annette; Reichrath, Jörg; Jorde, Rolf; Elmadfa, Ibrahim; Vieth, Reinhold; Scragg, Robert; Calvo, Mona S; Van Schoor, Natasja M; Bouillon, Roger; Lips, Paul; Itkonen, Suvi T; Martineau, Adrian R; Lamberg-Allardt, Christel; Zittermann, Armin (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-07-17)
      Vitamin D deficiency can lead to musculoskeletal diseases such as rickets and osteomalacia, but vitamin D supplementation may also prevent extraskeletal diseases such as respiratory tract infections, asthma exacerbations, pregnancy complications and premature deaths. Vitamin D has a unique metabolism as it is mainly obtained through synthesis in the skin under the influence of sunlight (i.e., ...
    • The relation between serum parathyroid hormone (PTH) and blood pressure. The Tromsø study 

      Jorde, Rolf (Journal article; Tidsskriftartikkel, 2006)
      The objective of the present cross-sectional epidemiological study from Tromsø, North Norway was to evaluate the relation between blood pressure and serum parathyroid hormone (PTH). 10419 subjects were invited to participate in the fifth Tromsø study and 8128 attended. 7954 subjects had serum PTH measured, and among these, information on blood pressure medication was available in 5841 subjects (2554 ...
    • Response to Letter to the Editor from Dalan: "Vitamin D Supplementation for Prevention of Type 2 Diabetes Mellitus: To D or Not to D?" 

      Pittas, Anastassios G.; Jorde, Rolf; Kawahara, Tetsuya; Dawson-Hughes, Bess (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-30)
      We thank Rinkoo Dalan for the comments on our paper (1, 2). We agree that although the reduction in diabetes risk with vitamin D supplementation among people at high risk for diabetes appears to be moderate (~ 12% relative risk reduction compared to placebo) (3), certain individuals may derive a higher (or lower) benefit based on certain characteristics. For example, in the simplest demonstration ...
    • The role of Vitamin D binding protein, total and free 25-hydroxyvitamin D in diabetes 

      Jorde, Rolf (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-02-19)
      Vitamin D is important for bone health, but may also have extra-skeletal effects. Vitamin D and its binding protein DBP have immunological effects and may therefore be important in the development of type 1 diabetes (T1DM), and low serum levels of 25-hydroxyvitamin D (25(OH)D) are associated with later development of type 2 diabetes (T2DM). However, it has so far been difficult to convincingly show ...
    • Seasonal changes in vitamin D-effective UVB availability in Europe and associations with population serum 25-hydroxyvitamin D 

      O'Neill, Colette M; Kazantzidis, Andreas; Ryan, Mary J; Barber, Niamh; Sempos, Christopher T.; Durazo-Arvizu, Ramon A.; Jorde, Rolf; Grimnes, Guri; Eiriksdottir, Gudny; Gudnason, Vilmundur; Cotch, Mary Frances; Kiely, Mairead; Webb, Ann R; Cashman, Kevin D (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-30)
      Low vitamin D status is common in Europe. The major source of vitamin D in humans is ultraviolet B (UVB)-induced dermal synthesis of cholecalciferol, whereas food sources are believed to play a lesser role. Our objectives were to assess UVB availability (Jm−2) across several European locations ranging from 35° N to 69° N, and compare these UVB data with representative population serum 25-hydroxyvitamin ...
    • Serum PTH is not a good marker for defining a threshold for vitamin D deficiency 

      Jorde, Rolf; Grimnes, Guri (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-01)
      <i>Objective</i>: In addition to its skeletal effects, vitamin D may also be important for health in general. It is uncertain what level of serum 25-hydroxyvitamin D (25(OH)D), marker of vitamin D status, is sufficient for these effects. With decreasing serum 25(OH)D levels there is an increase in serum PTH. The point at which this occurs has been considered as a threshold for vitamin D sufficiency. ...
    • Smoking and other determinants of bone turnover 

      Jorde, Rolf; Stunes, Astrid Kamilla; Kubiak, Julia Magdalena; Grimnes, Guri; Thorsby, Per Medbøe; Syversen, Unni (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-11-25)
      The balance between bone resorption and formation may be assessed by measurement of bone turnover markers (BTMs), like carboxyl-terminal cross-linked telopeptide of type 1 collagen (CTX-1) and procollagen type 1 amino-terminal propeptide (P1NP). Smoking has been shown to influence bone turnover and to reduce bone mass density (BMD), the exact mechanism for this is, however, not settled. In this ...
    • Staphylococcus aureus nasal carriage is associated with serum 25-hydroxyvitamin D levels, gender and smoking status. The Tromso Staph and Skin Study 

      Olsen, Karina; Falch, Birgit Margrethe; Danielsen, Kjersti; Johannessen, Mona; Sollid, Johanna U Ericson; Thune, Inger; Grimnes, Guri; Jorde, Rolf; Simonsen, Gunnar Skov; Furberg, Anne-Sofie (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
      Vitamin D induces the expression of antimicrobial peptides with activity against Staphylococcus aureus. Thus, we studied the association between serum 25-hydroxyvitamin D (25(OH)D) and S. aureus nasal colonization and carriage. Nasal swabs, blood samples and clinical data from 2,115 women and 1,674 men, aged 30–87 years, were collected in the Tromsø Staph and Skin Study 2007–08, as part of the ...