Yngve Figenschau

Effects of vitamin D supplementation on symptoms of depression in overweight and obese subjects: randomized double blind trial.

Objectives.  The objective of the present study was to examine the cross‐sectional relation between serum 25‐hydoxyvitamin D [25‐(OH) D] levels and depression in overweight and obese subjects and to assess the effect of vitamin D supplementation on depressive symptoms.

No significant effect on bone mineral density by high doses of vitamin D3 given to overweight subjects for one year.

BackgroundIn meta-analyses supplementation with vitamin D appears to reduce incidence of fractures, and in cross-sectional studies there is a positive association between serum 25-hydroxyvitamin D (25(OH)D) levels and bone mineral density (BMD). However, the effect of supplementation with high doses of vitamin D on BMD is more uncertain and could in theory have both positive and negative effects.MethodsThe study was a one year, double blind placebo-controlled intervention trial performed at the University Hospital of North Norway. 421 subjects, 21 - 70 years old, were included and 312 completed the study. The subjects were randomized to vitamin D3 40.000 IU per week (DD group), vitamin D3 20.000 IU per week (DP group), or placebo (PP group). All subjects were given 500 mg calcium daily. Serum 25(OH)D, osteoprotegrin (OPG), receptoractivator of nuclear factor-kappaB ligand (RANKL), and BMD at the lumbar spine and the hip were measured before and at the end of the study.ResultsAt baseline the mean serum 25(OH)D levels were 58 nmol/L (all subjects) and increased to 141 and 100 nmol/L in the DD and DP groups, respectively. After one year, no significant differences were found between the three groups regarding change in BMD, serum OPG or RANKL.ConclusionsSupplementation with high doses of vitamin D for one year does not appear to have a negative effect on BMD in healthy subjects. In order to disclose a positive effect, subjects with low BMD and/or low serum 25(OH)D levels need to be studied.Trial registrationThe trial was registered at ClinicalTrials.gov (NCT00243256).

Tracking of Serum 25-Hydroxyvitamin D Levels During 14 Years in a Population-based Study and During 12 Months in an Intervention Study

Low serum 25-hydroxyvitamin D (25(OH)D) levels are associated with risk factors for cardiovascular disease, and they also appear to predict later development of type 2 diabetes, cancer, and an increased mortality rate. These predictions are all based on a single 25(OH)D measurement, but so far there are no known reports on tracking of serum 25(OH)D levels. In the present Norwegian study, serum 25(OH)D levels were measured 1) in 2,668 subjects in the 1994 and 2008 Tromsø surveys and 2) every third month for 1 year in 94 subjects randomly assigned to placebo in a vitamin D intervention study. There was a marked seasonal variation in 25(OH)D, and, depending on the method of adjusting for season, the correlation coefficient between serum 25(OH)D measurements from 1994 and 2008 ranged from 0.42 to 0.52. In the 1-year intervention study, the correlation between baseline and 12-month values was 0.80. Apart from the effect of season, changes in weight, intake of vitamin D, and physical activity were related to change in serum 25(OH)D levels. Tracking of serum 25(OH)D appears similar to that for blood pressure and serum lipids, and it provides some support for the use of a single 25(OH)D measurement to predict future health outcomes.

No improvement in cardiovascular risk factors in overweight and obese subjects after supplementation with vitamin D3 for 1 year

Abstract.  Jorde R, Sneve M, Torjesen P, Figenschau Y (University of Tromsø, Tromsø; Medical Clinic University Hospital of North Norway, Tromsø; University Hospital of North Norway, Tromsø; Aker University Hospital, Oslo; University Hospital of North Norway, Tromsø; and University of Tromsø, Tromsø; Norway). No improvement in cardiovascular risk factors in overweight and obese subjects after supplementation with vitamin D3 for 1 year. J Intern Med 2010; 267:462–472.

Supplementation with cholecalciferol does not result in weight reduction in overweight and obese subjects

OBJECTIVE Investigate whether cholecalciferol supplementation leads to weight loss in overweight and obese adults. DESIGN Randomized double blind clinical trial with 20,000 IU cholecalciferol twice a week, or 20,000 IU once a week plus placebo, or placebo twice a week, for 12 months. All subjects were given 500 mg calcium supplementation. METHODS Four hundred and forty five healthy, overweight, and obese men and women (age 21-70 years, body mass index (BMI) 28.0-47.0 kg/m(2)). Body weight, fatness, and fat distribution parameters were measured by dual-energy X-ray absorptiometry and anthropometry, blood samples and 24-h urinary samples were collected. RESULTS At baseline, there were no significant differences between the groups, but there was a significant inverse relation between serum 25-hydroxyvitamin D (25(OH)D) levels and BMI, and a significant positive association between calorie intake and BMI. Three hundred and thirty four subjects completed the study. During the study, there was no significant change in weight, waist-to-hip ratio (WHR) or percentage body fat in any of the groups, nor between them. Parathyroid hormone decreased and 25(OH)D increased significantly in both groups receiving cholecalciferol, and serum levels of 25(OH)D stabilized after 3 months. Serum calcium was unchanged in all groups. Urinary calcium excretion increased in all groups, but there was no significant difference between the groups. Weekly dosage of 20,000-40,000 IU cholecalciferol for 12 months was associated with a low risk of adverse effects, at least in overweight and obese adults living at latitude 70 degrees N. CONCLUSION Significant weight reduction in overweight and obese subjects is unlikely to occur with cholecalciferol supplementation.

Serum lipid levels in relation to serum thyroid‐stimulating hormone and the effect of thyroxine treatment on serum lipid levels in subjects with subclinical hypothyroidism: the Tromsø Study

Objective.  To evaluate the relation between serum thyroid‐stimulating hormone (TSH) and lipids.

Low serum 25-hydroxyvitamin D levels are associated with increased all-cause mortality risk in a general population: the Tromsø study.

OBJECTIVE Ecologic and observational studies have suggested an association between serum 25-hydroxyvitamin D (25(OH)D) levels and cardiovascular disease (CVD) risk factors, CVD mortality, and cancer mortality. Based on this, low serum 25(OH)D levels should be associated with higher all-cause mortality in a general population. This hypothesis was tested in the present study. DESIGN The Tromsø study is a longitudinal population-based multipurpose study initiated in 1974 with focus on lifestyle-related diseases. Our data are based on the fourth Tromsø study carried out in 1994-1995. METHODS Information about death and cause of death was registered by obtaining information from the National Directory of Residents and the Death Cause Registry. Serum 25(OH)D was measured in 7161 participants in the fourth Tromsø study. Results are presented for smokers (n=2410) and non-smokers (n=4751) separately as our immunoassay seems to overestimate 25(OH)D levels for smokers. RESULTS During a mean 11.7 years of follow-up, 1359 (19.0%) participants died. In multivariate regression models, there was a significantly increased risk of all-cause mortality (hazard ratio (HR) 1.32, confidence interval (CI) 1.07-1.62) among non-smoking participants in the lowest 25(OH)D quartile when compared with participants in the highest quartile. Equivalent results for smokers were not significant (HR 1.06, CI 0.83-1.35). CONCLUSIONS Low serum 25(OH)D levels were associated with increased all-cause mortality for non-smokers, but the results did not reach statistical significance for smokers. However, low 25(OH)D levels are known to be associated with impaired general health, and randomized controlled studies are needed to address the question of causality.

No effect of supplementation with cholecalciferol on cytokines and markers of inflammation in overweight and obese subjects.

Epidemiological studies indicate a relation between vitamin D status and autoimmune diseases, and in vitro studies demonstrate an effect of 1,25-dihydroxyvitamin D on immune activation. However, the relation between serum levels of 25-hydroxyvitamin D (25(OH)D) and the effect of vitamin D supplementation on serum levels of cytokines are not settled. In the present study interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12, IL-13, IL-17, intercellular adhesion molecule-1, interferon-gamma, monocyte chemotactic protein-1, and high sensitivity C-reactive protein, were measured in 437 overweight subjects and 324 completed a one year intervention with 40,000 IU vitamin D per week (group DD), 20,000 IU vitamin D per week (group DP), or placebo (group PP). No consistent relations between serum levels of the cytokines and 25(OH)D were found at baseline. In the intervention study, there was no difference in delta values (value at end of study minus value at inclusion) between the three groups regarding the individual cytokines measured, nor was there any indication of a polarization of the T cells towards a Th2 dominant type. In conclusion, we were not able to demonstrate with certainty any significant relation between serum levels of 25(OH)D levels and a number of cytokines and markers of inflammation.

High serum 25-hydroxyvitamin D concentrations are associated with a favorable serum lipid profile

Background/Objectives:Low serum 25-hydroxyvitamin D (25(OH)D) concentrations are related to increased mortality. One possible explanation could be an association between serum 25(OH)D and serum lipids.Subjects/Methods:The study was performed at the University of Tromsø, Northern Norway. In total, 8018 nonsmoking and 2087 smoking subjects were included in a cross-sectional study performed in 2008, and 1762 nonsmoking and 397 smoking subjects in a longitudinal study from 1994/1995 to 2008. Nonfasting serum 25(OH)D, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), LDL-C/HDL-C ratio and triacylglycerol (TAG) were measured.Results:After adjustment for gender, age, sample month and body mass index in the cross-sectional study, there was a significant increase in serum TC, HDL-C and LDL-C, and a significant decrease in serum LDL-C/HDL-C ratio and TAG across increasing serum 25(OH)D quartiles. For serum HDL-C and TAG in nonsmokers the differences between the means for the highest and lowest serum 25(OH)D quartiles were 6.0 and 18.5%, respectively. In the longitudinal study, an increase in serum 25(OH)D was associated with a significant decrease in serum TAG.Conclusions:There is a cross-sectional association between serum 25(OH)D and serum lipids, and a longitudinal association over 14 years between serum 25(OH)D and TAG, which may contribute to explain the relation between low serum 25(OH)D concentrations and mortality.

Testosterone treatment in elderly men with subnormal testosterone levels improves body composition and BMD in the hip

Our intention was to examine if subnormal testosterone levels in older men were associated with a reduction in quality of life and physical and mental health, and secondly to examine if testosterone treatment could improve these conditions. We performed a nested case–control study and a 1-year testosterone intervention study. Men with subnormal testosterone had significantly higher weight, fat mass and abdominal adipose tissue. They also had significantly higher glucose and insulin levels, and they had higher triglyceride levels. Testosterone treatment had a large impact on body composition with reduced fat mass and abdominal adipose tissue and increased fat-free mass, but it did not affect weight and glucose and lipid metabolism. Bone mineral density in the hip was significantly higher after the testosterone treatment. Older men with subnormal testosterone levels had an unfavorable metabolic profile. Testosterone treatment improved body composition, but it did not reverse the unfavorable metabolic profile.