Serum 25-hydroxyvitamin D levels and incident falls in older women.

Three hundred eighty-seven home-dwelling older women were divided into quartiles based on mean serum 25-hydroxyvitamin D (S-25(OH)D) levels. The rates of falls and fallers were about 40% lower in the highest S-25(OH)D quartile compared to the lowest despite no differences in physical functioning, suggesting that S-25(OH)D levels may modulate individual fall risk. INTRODUCTION: Vitamin D supplementation of 800 IU did not reduce falls in our previous 2-year vitamin D and exercise RCT in 70-80 year old women. Given large individual variation in individual responses, we assessed here effects of S-25(OH)D levels on fall incidence. METHODS: Irrespective of original group allocation, data from 387 women were explored in quartiles by mean S-25(OH)D levels over 6-24 months; means (SD) were 59.3 (7.2), 74.5 (3.3), 85.7 (3.5), and 105.3 (10.9) nmol/L. Falls were recorded monthly with diaries. Physical functioning and bone density were assessed annually. Negative binomial regression was used to assess incidence rate ratios (IRRs) for falls and Cox-regression to assess hazard ratios (HR) for fallers. Generalized linear models were used to test between-quartile differences in physical functioning and bone density with the lowest quartile as reference. RESULTS: There were 37% fewer falls in the highest quartile, while the two middle quartiles did not differ from reference. The respective IRRs (95% CI) for falls were 0.63 (0.44 to 0.90), 0.78 (0.55 to 1.10), and 0.87 (0.62 to 1.22), indicating lower falls incidence with increasing mean S-25(OH)D levels. There were 42% fewer fallers (HR 0.58; 040 to 0.83) in the highest quartile compared to reference. Physical functioning did not differ between quartiles. CONCLUSIONS: Falls and faller rates were about 40% lower in the highest S-25(OH)D quartile despite similar physical functioning in all quartiles. Prevalent S-25(OH)D levels may influence individual fall risk. Individual responses to vitamin D treatment should be considered in falls prevention.

Association of serum 25-hydroxyvitamin D concentration with HLA-B, -DRB1 and -DQB1 genetic polymorphisms.

BACKGROUND/OBJECTIVES: The human leukocyte antigen (HLA) gene region associates with the risk for several autoimmune diseases, including type 1 diabetes. An association between vitamin D deficiency and several autoimmune diseases has been suggested. We tested the association between serum 25-hydroxyvitamin D (25OHD) concentrations and HLA alleles in pregnant Finnish women. SUBJECTS/METHODS: HLA-B (n=395), HLA-DRB1 (n=501) and HLA-DQB1 (n=475) alleles were genotyped in pregnant women (mothers of children who later developed type 1 diabetes and mothers of non-diabetic children). HLA-B alleles were divided into supertypes that share similar peptide-binding specificity. Serum 25OHD concentration had been previously measured in these women from sera collected during the first trimester of pregnancy. Multiple testing was controlled for using the false discovery rate method. RESULTS: An association was found between 25OHD concentration and HLA-B44 supertype (P=0.009); women with HLA-B44 supertype (B*18, B*37, B*40 and B*44 alleles) had lower 25OHD concentrations. No association was found between HLA-DRB1 or -DQB1 alleles and 25OHD concentration. CONCLUSIONS: In this study we found for the first time an association between HLA genetic polymorphisms and 25OHD concentration. In future studies, the mechanistic background of this association and the role of vitamin D in the regulation of HLA gene expression should be investigated.

No association between vitamin D and ß-cell autoimmunity in Finnish and Estonian children.

BACKGROUND: Vitamin D has immunomodulatory properties, such as regulation of FOXP3 expression and regulatory T-cell activity. Our aim was to investigate whether plasma 25-hydroxyvitamin D [25(OH)D] concentrations associate with the development of ß-cell autoimmunity and the transcriptional activity of FOXP3 or vitamin D3 convertase gene (CYP27B1) in CD4+ memory T cells. METHODS: We studied 83 Finnish and 32 Estonian children participating in the DIABIMMUNE and DIPP studies. Twenty-nine Finnish and six Estonian children tested positive for at least one diabetes-associated autoantibody. The plasma concentrations of 25(OH)D and 1,25(OH)2D were analysed with an enzyme immunoassay. Gene expression of FOXP3 and CYP27B1 in the isolated CD4+ memory T cells was studied with reverse transcription quantitative polymerase chain reaction. RESULTS: Vitamin D status did not differ between subjects positive and negative for ß-cell autoantibodies. Finnish children had higher vitamin D status than Estonian children (p < 0.001). FOXP3 expression was higher in Estonian CD4+ memory T-cell samples than in Finnish samples (p < 0.01) even when including in both groups only children with serum 25(OH)D concentrations in the range of 50-80 nmol/L (p < 0.001). CONCLUSIONS: These findings do not support a crucial role of circulating 25(OH)D as a regulator of ß-cell autoimmunity or FOXP3 expression.

Vitamin D: do we get enough? A discussion between vitamin D experts in order to make a step towards the harmonisation of dietary reference intakes for vitamin D across Europe.

UNLABELLED: On September 29, 2011, acknowledged experts in the field of vitamin D, mainly European, were brought together in order to discuss the recent scientific advances in relation to vitamin D: the current requirements and associations with various health outcomes. In this article, the discussions resulting from the meeting are summarized. INTRODUCTION: Several groups at risk for developing vitamin D insufficiency have been identified. Accordingly, reviews indicate that a significant percentage of the population worldwide have serum 25-hydroxyvitamin D levels below 50 nmol/l. In addition to the role of vitamin D in bone health, recent studies suggest that it may play a pivotal role in other systems, e.g., the cardiovascular system, pancreas, muscle, immune system and brain. Most evidence, however, is obtained from observational studies and yet inconclusive. METHODS: To exchange and broaden knowledge on the requirements for vitamin D and its effect on various health outcomes, a workshop entitled "Vitamin D Expert Meeting: Do we get enough?", was organized. RESULTS: Despite low vitamin D levels worldwide, consensus on the definition of deficiency is not yet reached. In order to define cut-off points for vitamin D whilst taking into account extraskeletal health effects, randomized controlled trials in these fields are warranted. The experts do emphasize that there is evidence to suggest an important role for vitamin D in the maintenance of optimal bone health at all ages and that vitamin D supplementation, in most studies co-administered with calcium, reduces fracture risk in the senior population. CONCLUSION: To reach a serum 25-hydroxyvitamin D level of 50 nmol/l older adults aged ≥65 years are therefore recommended to meet a mean daily vitamin D intake of 20 µg (800 IU), which is best achieved with a supplement.

Serum 25-hydroxyvitamin D level during early pregnancy and type 1 diabetes risk in the offspring.

AIMS/HYPOTHESIS: Vitamin D deficiency during the fetal period or infancy is one of the suggested environmental factors for type 1 diabetes and for its increasing incidence. To test this hypothesis we compared serum 25-hydroxyvitamin D (25(OH)D) levels during early pregnancy in mothers of children who subsequently developed type 1 diabetes (case mothers) with mothers of non-diabetic healthy children (control mothers) of the same age. METHODS: Children with type 1 diabetes were identified from the nationwide prescription register. 25(OH)D concentration was measured from serum samples collected during the first trimester of pregnancy from all Finnish women (Finnish Maternity Cohort). A total of 343 case mothers and 343 control mothers were included in the study. Samples were collected throughout the year. Samples from case and control mothers were matched on the day of collection. RESULTS: Mean 25(OH)D levels in case mothers (43.9 nmol/l) and control mothers (43.7 nmol/l) were not different. Of all mothers, 481 (70.1%) were vitamin D-deficient or -insufficient. CONCLUSIONS/INTERPRETATION: No difference was found in serum 25(OH)D concentrations during first trimester of pregnancy between mothers whose children later on developed type 1 diabetes, and mothers of non-diabetic ' healthy' children of the same age. It is difficult to detect possible effects of mothers' vitamin D deficiency during early pregnancy on the development of type 1 diabetes in the offspring in this population, as such a large proportion of mothers were vitamin D-deficient or -insufficient.

Maternal vitamin D status affects bone growth in early childhood--a prospective cohort study.

UNLABELLED: In this prospective study, 87 children were followed up from birth to 14 months with data on maternal vitamin D status during the pregnancy. Postnatal vitamin D supplementation improved vitamin D status but only partly eliminated the differences in bone variables induced by maternal vitamin D status during the fetal period. INTRODUCTION: Intrauterine nutritional deficits may have permanent consequences despite improved nutritional status postnatally. We evaluated the role of prenatal and postnatal vitamin D status on bone parameters in early infancy. METHODS: Eighty-seven children were followed from birth to 14 months. Background data were collected with a questionnaire and a 3-day food record. At 14 months bone variables were measured with peripheral computed tomography (pQCT) from the left tibia. Serum 25-OHD and bone turnover markers were determined. Findings were compared with maternal vitamin D status during pregnancy. RESULTS: The children were divided into two groups based on vitamin D status during pregnancy. Despite discrepant S-25-OHD at baseline (median 36.3 vs. 52.5 nmol/l, p < 0.001), the values at 14 months were similar (63 vs. 66 nmol/l, p = 0.58) in Low D and High D. Serum 25-OHD increased more in Low D (p < 0.001) despite similar total intake of vitamin D (mean 12.3 µg/day). In Low D, tibial bone mineral content (BMC) was lower at birth but BMC gain was greater (multivariate analysis of variance [MANOVA]; p = 0.032) resulting in similar BMC at 14 months in the two groups. In High D, tibial total bone cross-sectional area was higher at baseline; the difference persisted at 14 months (MANOVA; p = 0.068). Bone mineral density (BMD) and ΔBMD were similar in the two groups. CONCLUSIONS: Postnatal vitamin D supplementation improved vitamin D status but only partly eliminated the differences in bone variables induced by maternal vitamin D status during the fetal period. Further attention should be paid to improving vitamin D status during pregnancy.

Proceedings of the Rank Forum on Vitamin D.

The Rank Forum on Vitamin D was held on 2nd and 3rd July 2009 at the University of Surrey, Guildford, UK. The workshop consisted of a series of scene-setting presentations to address the current issues and challenges concerning vitamin D and health, and included an open discussion focusing on the identification of the concentrations of serum 25-hydroxyvitamin D (25(OH)D) (a marker of vitamin D status) that may be regarded as optimal, and the implications this process may have in the setting of future dietary reference values for vitamin D in the UK. The Forum was in agreement with the fact that it is desirable for all of the population to have a serum 25(OH)D concentration above 25 nmol/l, but it discussed some uncertainty about the strength of evidence for the need to aim for substantially higher concentrations (25(OH)D concentrations>75 nmol/l). Any discussion of 'optimal' concentration of serum 25(OH)D needs to define 'optimal' with care since it is important to consider the normal distribution of requirements and the vitamin D needs for a wide range of outcomes. Current UK reference values concentrate on the requirements of particular subgroups of the population; this differs from the approaches used in other European countries where a wider range of age groups tend to be covered. With the re-emergence of rickets and the public health burden of low vitamin D status being already apparent, there is a need for urgent action from policy makers and risk managers. The Forum highlighted concerns regarding the failure of implementation of existing strategies in the UK for achieving current vitamin D recommendations.

Measurement of 25-hydroxyvitamin D in the clinical laboratory: current procedures, performance characteristics and limitations.

In this review we describe procedures, performance characteristics and limitations of methods available for the measurement of 25-hydroxyvitamin (25OHD) since the year 2000. The two main types of methods are competitive immunoassay and those based on chromatographic separation followed by non-immunological direct detection (HPLC, LC-MS/MS). Lack of a reference standard for 25OHD has, until recently, been a major issue resulting in poor between-method comparability. Fortunately this should soon improve due to the recent introduction of a standard reference material in human serum (SRM 972) from the National Institute of Standards and Technology (NIST). For immunoassay, specificity can be an issue especially in relation to the proportion of 25OHD2 that is quantified whereas HPLC and LC-MS/MS methods are able to measure the two major vitamin D metabolites 25OHD2 and 25OHD3 independently. HPLC and LC-MS/MS require more expensive equipment and expert staff but this can be offset against lower reagent costs. Increasingly procedures are being developed to semi-automate or automate HPLC and LC-MS/MS but run times remain considerably longer than for immunoassays especially if performed on automated platforms. For most HPLC and LC-MS/MS methods extraction and procedural losses are corrected for by the inclusion of an internal standard which, in part, may account for higher results compared to immunoassay. In general precision of immunoassay, HPLC and LC-MS/MS are comparable and all have the required sensitivity to identify severe vitamin D deficiency. Looking to the future it is hoped that the imminent introduction of a standard reference method (or methods) for 25OHD will further accelerate improvements in between method comparability.

Maternal vitamin D status determines bone variables in the newborn.

CONTEXT: Vitamin D regulates 3% of the human genome, including effects on bone health throughout life. Maternal vitamin D status may program neonatal skeletal development. The objective here was to determine the association of mothers' vitamin D status with bone variables of their newborns. SUBJECTS AND METHODS: In a birth hospital, pregnant women (n = 125) participated in a cross-sectional study with a longitudinal follow-up of the pregnancy. The mean (sd) values for age, body mass index before pregnancy, pregnancy weight gain, and total vitamin D intake in mothers were 31 (4) yr, 23.5 (3.7) kg/m(2), 13.1 (4.3) kg, and 14.3 (5.8) microg, respectively. All newborns were full-term, 99% were appropriate for gestational age, and 53% were boys. Blood samples were collected from mothers during the first trimester and 2 d postpartum and from umbilical cords at birth for analysis of serum 25-hydroxyvitamin D (S-25-OHD), PTH, and bone remodeling markers. Bone variables were measured by pQCT at the 20% site of the newborn tibia on an average of 10 (11) d postpartum. Bone contour was analyzed with a single threshold of 180 mg/mm(3) for the detection of total bone mineral density (BMD), bone mineral content (BMC), and cross-sectional area (CSA). RESULTS: Mean S-25-OHD was 41.0 (13.6), 45.1 (11.9), and 50.7 (14.9) nmol/liter during the first trimester, postpartum, and in the umbilical cord, respectively. The median value of the individual means for first trimester and the 2-d postpartum S-25-OHD was 42.6 nmol/liter, which was used as cutoff to define two equal-sized groups. Groups are called below median and above median in the text. Newborns below median were heavier (P = 0.05), and 60% were boys. Tibia bone mineral content was 0.047 (95% confidence interval, 0.011-0.082) g/cm higher (P = 0.01), and cross-sectional area was 12.3 (95% confidence interval, 2.0-22.6) mm(2) larger (P = 0.02), but no difference in bone mineral density was observed, above median compared with below median group. These results were adjusted for newborn Z-score birth weight, maternal height, and newborn age at the measurement. A positive, significant correlation was observed between remodeling markers in mothers at different time points and above median group in the cord. CONCLUSIONS: Although the mean total intake of vitamin D among mothers met current Nordic recommendations, 71% of women and 15% of newborns were vitamin D deficient during the pregnancy. Our results suggest that maternal vitamin D status affects bone mineral accrual during the intrauterine period and influences bone size. More efforts should be made to revise current nutrition recommendations for pregnant women that may have permanent effects on the well-being of children.

Narrowband ultraviolet B course improves vitamin D balance in women in winter.

BACKGROUND: Vitamin D insufficiency is common in winter in the Nordic countries. OBJECTIVES: To examine whether a short course of narrowband ultraviolet B (NB-UVB) improves vitamin D balance. METHODS: Fifty-six healthy, white women (mean age 41 years) volunteered and 53 completed the study. NB-UVB exposures were given on seven consecutive days either on the whole body (n = 19), on the head and arms (n = 9) or on the abdomen (n = 14). Similarly, seven solar simulator exposures were given on the face and arms (n = 11). The cumulative UVB dose was 13 standard erythema doses in all regimens. Serum calcidiol (25-hydroxyvitamin D) concentration was measured by radioimmunoassay before and after the NB-UVB exposures. Follow-up samples were taken from the whole-body NB-UVB group at 2 months. RESULTS: At onset 41 women (77%) had vitamin D insufficiency (calcidiol < 50 nmol L(-1)) and six (11%) had vitamin D deficiency (calcidiol < 25 nmol L(-1)). Calcidiol concentration increased significantly, by a mean of 11.4 nmol L(-1) when NB-UVB was given on the whole body, by 11.0 nmol L(-1) when given on the head and arms and by 4.0 nmol L(-1) when given on the abdomen. Solar simulator exposures given on the face and arms increased calcidiol by 3.8 nmol L(-1). After 2 months serum calcidiol was still higher than initially in the group who received NB-UVB exposures on the whole body. CONCLUSIONS: NB-UVB exposures given on seven consecutive days on different skin areas of healthy women significantly improved serum calcidiol concentration. A short low-dose NB-UVB course can improve vitamin D balance in winter.

Does vitamin D supplementation of healthy Danish Caucasian girls affect bone turnover and bone mineralization?

INTRODUCTION: A high peak bone mass may be essential for reducing the risk of osteoporosis later in life and a sufficient vitamin D level during puberty may be necessary for optimal bone accretion and obtaining a high peak bone mass. Dietary intake and synthesis during winter of vitamin D might be limited but the effect of vitamin D supplementation in adolescence on bone mass is not well established. OBJECTIVE: To investigate the effect of supplementation with 5 and 10 microg/day vitamin D(3) for 12 months in 11- to 12-year-old girls on bone mass and bone turnover as well as the possible influence of VDR and ER genotype on the effect of the supplementation. METHODS: The girls (n=221) were randomized to receive either 5 microg or 10 microg vitamin D(3) supplementation per day or placebo for 12 months. Whole body and lumbar spine bone mass measured by DXA and pubertal status were determined at baseline and after 12 months whereas physical activity and dietary intake of calcium and vitamin D were assessed at baseline. Serum (S) 25-hydroxyvitamin D (25OHD), S-osteocalcin, S-parathyroid hormone, S-calcium, S-inorganic phosphate, urinary (U) pyridinoline (Pyr) and deoxpyridinoline (Dpyr) were measured at baseline and after 6 and 12 months. RESULTS: The S-25OHD concentration increased (p<0.001) relative to the baseline values in the groups receiving either 5 microg/day (mean+/-SD; 11.0+/-10.3 nmol/l, baseline 41.9+/-17.6 nmol/l) or 10 microg/day (13.3+/-11.8 nmol/l, baseline 44.4+/-16.6 nmol/l) vitamin D(3) for 12 months compared to placebo (-3.1+/-9.8 nmol/l, baseline 43.4+/-17.1 nmol/l). There was no effect of vitamin D-supplementation on biomarkers for bone turnover or on whole body or spine bone mineral augmentation. However, vitamin D supplementation increased whole body bone mineral density (BMD) (p=0.007) and bone mineral content (BMC) (p=0.048) in the FF VDR genotype but not in the Ff or ff VDR genotypes. CONCLUSION: Supplementation with vitamin D (5 or 10 microg/day) over 12 months increased the S-25OHD concentration but there was no effect on indices of bone health in the entire group of girls. However, there was an effect on BMD for a subgroup with the FF VDR genotype indicating an influence of genotype.

Associations of vitamin D receptor, calcium-sensing receptor and parathyroid hormone gene polymorphisms with calcium homeostasis and peripheral bone density in adult Finns.

BACKGROUND: Thus far the search for osteoporosis candidate genes has focused less attention on the regulation of calcium homeostasis. Associations of vitamin D receptor (VDR) FokI, calcium-sensing receptor (CaSR) A986S and parathyroid hormone (PTH) BstBI polymorphisms with calcium homeostasis and peripheral bone density were investigated in adult Finns. METHODS: The subgroup of the population-based FINRISK survey consists of 339 healthy adults aged 31-43 years. Lifestyle data were assessed with questionnaires and food diaries. DNA was isolated from blood, and biochemical determinants of calcium metabolism were measured from blood and 24-hour urine samples. Bone mineral density (BMD) was measured using the DXA method at the distal forearm and by quantitative ultrasound (broadband ultrasound attenuation and speed of sound) at the calcaneus. Subjects were genotyped for VDR FokI, CaSR A986S and PTH BstBI polymorphisms. RESULTS: The CaSR 986S allele was associated with higher serum ionized calcium (p = 0.014). Forearm BMD was lowest for the PTH BstBI genotype bb in males (p = 0.023). VDR FokI and PTH BstBI polymorphisms showed a significant interaction on serum PTH (p = 0.010). The other gene-gene or diet-gene interactions studied showed no significant results. CONCLUSIONS: VDR, CaSR and PTH contribute to the genetic regulation of calcium homeostasis and peripheral bone density.

Heliotherapy improves vitamin D balance and atopic dermatitis.

BACKGROUND: Vitamin D insufficiency during winter is common in the Nordic countries. Heliotherapy (HT) may heal atopic dermatitis (AD) but its effect on vitamin D balance has not been examined. OBJECTIVES: To study the effect of HT on serum calcidiol (25-hydroxyvitamin D) concentration and on healing of AD. METHODS: Twenty-three adult patients with AD received a 2-week course of HT in the Canary Islands in either January or March 2005. Daily solar ultraviolet (UV) radiation was measured and personal UV exposure calculated as standard erythema doses (SED). Blood samples were taken during HT and during a 1-2 month follow-up. Serum calcidiol concentration was measured by radioimmunoassay. Healing of AD was examined by SCORAD index. RESULTS: Before HT 17 (74%) AD patients had vitamin D insufficiency (calcidiol < 50 nmol L(-1)) and four patients high (> 80 nmol L(-1)) serum calcidiol values. The median personal UV dose during the 2-week HT course was 60 SED in the January group and 109 SED in the March group. Serum calcidiol concentration increased significantly in both groups, by 13.4 and 24.0 nmol/L(-1), respectively, and after HT only four (17%) patients had vitamin D insufficiency. SCORAD improved from 34 to 9 in the January HT group and from 30 to 9 in the March group. CONCLUSIONS: A 2-week course of HT significantly improved vitamin D balance by increasing serum calcidiol concentration, and caused a marked healing of AD. These parallel positive responses should be taken into account when the benefits of HT are considered.

Pakistani immigrant children and adults in Denmark have severely low vitamin D status.

OBJECTIVE: To determine vitamin D and bone status in adolescent girls, pre-menopausal women and men of Pakistani origin, to single out determinants of vitamin D status and to determine the association between vitamin D status, bone metabolism and bone status. SUBJECTS/METHODS: Cross-sectional study, Copenhagen (55 degrees N), January-November. Serum 25-hydroxyvitamin D (S-25OHD), serum intact parathyroid hormone (S-iPTH), bone turnover markers and whole body and lumbar spine bone mineral density were measured. Sun, smoking and clothing habits, age, body mass index (BMI), and vitamin D and calcium from food and from supplements were recorded. Thirty-seven girls (median age, range: 12.2 years, 10.1-14.7), 115 women (36.2 years, 18.1-52.7) and 95 men (38.3 years, 17.9-63.5) of Pakistani origin (immigrants or descendants with Pakistani parents) took part in the study. RESULTS: Median concentration of S-25OHD was 10.9, 12.0 and 20.7 nmol/l for girls, women and men, respectively. Forty-seven per cent of the girls, 37% of the women and 24% of the men had elevated S-iPTH, and there was a negative relationship between S-iPTH and S-25OHD. Use of vitamin D-containing supplements had a positive association with S-25OHD for men (P=0.04) and women (P=0.0008). Twenty-one per cent of the women and 34% of the men had osteopenia. Neither S-25OHD nor S-iPTH was associated with lumbar spine or whole body bone mineral content. CONCLUSIONS: Severely low vitamin D status and elevated S-iPTH is common among Pakistani immigrants in Denmark. The low vitamin D status is not associated with bone markers or bone mass among relatively young Pakistanis.

Acute effects of different phosphorus sources on calcium and bone metabolism in young women: a whole-foods approach.

The recommended dietary phosphorus intake is exceeded in the typical Western diet. However, few studies have been conducted on the bioavailability and metabolic consequences of dietary phosphorus from different food sources. In this study, acute effects of dietary phosphorus from three different food sources and a phosphate supplement on calcium and bone metabolism were investigated. Sixteen healthy women aged 20-30 years were randomized to five controlled 24-hour study sessions, each subject serving as her own control. At the control session, calcium intake was ca. 250 mg and phosphorus intake ca. 500 mg. During the other four sessions, phosphorus intake was about 1,500 mg, 1,000 mg of which was obtained from meat, cheese, whole grains, or a phosphate supplement, respectively. The foods served were exactly the same during the phosphorus sessions and the control session; only phosphorus sources varied. Markers of calcium and bone metabolism were followed. Analysis of variance with repeated measures was used to compare the study sessions. Only the phosphate supplement increased serum parathyroid hormone (S-PTH) concentration compared with the control session (P = 0.031). Relative to the control session, meat increased markers of both bone formation (P = 0.045) and bone resorption (P = 0.049). Cheese decreased S-PTH (P = 0.0001) and bone resorption (P = 0.008). These data suggest that the metabolic response was different for different foods.

Vitamin D intake and status in Irish elderly women and adolescent girls.

AIM: To assess vitamin D status during summer and winter in Irish girls and elderly women, and to estimate vitamin D intake in these two age-groups. METHODS: Ambulatory free-living, elderly Irish women (aged 70-76 years; n = 43) and girls (aged 11-13 years; n = 17) were recruited. Fasting serums were collected during August/ September 2002 and February/March 2003 and analysed for 25 (OH) D by HPLC. RESULTS: Mean daily intakes of vitamin D were 4.6 microg and 2.1 microg in elderly women and girls, respectively. Serum 25 (OH) D was significantly lower (P<0.001) during winter than summer in both age-groups. Eight (20%) and one (during late summer) and sixteen (37.2%) and eight (47%) (during late winter) of the elderly women and girls, respectively, had inadequate vitamin D status (serum 25 (OH) D <40 nmol/l). CONCLUSION: Inadequate vitamin D status during winter time is quite common in elderly women and adolescent girls in Ireland.

Safety aspects and cholesterol-lowering efficacy of low fat dairy products containing plant sterols.

OBJECTIVE: The aim of this study was to investigate whether a plant sterol mixture would reduce serum cholesterol when added to low fat dairy products in subjects with hypercholesterolaemia, and to examine the effects of the mixture on the serum plant sterol and fat-soluble vitamin levels. DESIGN: A parallel, double-blind study. SETTING: The study was performed in three different locations in Finland. SUBJECTS: In total, 164 mildly or moderately hypercholesterolaemic subjects participated in the study. METHODS: The subjects were randomly divided into two groups: a plant sterol group and a control group. The subjects consumed the products for 6 weeks after a 3-week run-in period. The targeted plant sterol intake was 2 g/day in the sterol group. RESULTS: During the treatment period, there was a 6.5% reduction in serum total cholesterol in the sterol group while no change was observed in the control group (P<0.0005). Serum low-density lipoprotein (LDL) cholesterol was reduced by 10.4% in the sterol group and by 0.6% in the control group (P<0.00005). There was no change during the trial in serum high-density lipoprotein (HDL) cholesterol or triacylglycerol concentrations. The HDL/LDL cholesterol ratio increased by 16.1% in the sterol group and by 4.3% in the control group (P=0.0001). Serum plant sterol levels increased significantly (P=0.0001) in the sterol group. None of the fat-soluble vitamin levels decreased significantly when changes in serum total cholesterol were taken into account. The hypocholesterolaemic effect of sterol administration was not influenced by apolipoprotein E phenotype. CONCLUSIONS: Yoghurt, low-fat hard cheese and low-fat fresh cheese enriched with a plant sterol mixture reduced serum cholesterol in hypercholesterolaemic subjects and no adverse effects were noted in the dietary control of hypercholesterolaemia.

Food consumption and nutrient intakes with a special focus on milk product consumption in early pubertal girls in Central Finland.

OBJECTIVE: To evaluate the current status of dietary intakes in early pubertal girls with a special focus on milk products. DESIGN: Cross-sectional data using 3-day food records. SUBJECTS: Eight hundred and sixty girls, aged 10-12 years, at Tanner maturation stage I-III. RESULTS: The mean consumption of milk products (620 g day(-1)) was similar to that of a Finnish study in the 1980s, while the consumption of non-milk drinks (403 g day(-1)) had increased. Twelve per cent of the girls had a dairy-restricted diet and consumed significantly less milk products than girls with a non-restricted diet (465 vs. 644 g day(-1), P<0.001). Girls with low milk product consumption had the highest non-milk drinks consumption (P<0.001). The mean energy intake was 7.1 MJ day(-1). No major changes were found in the sources of nutrients. The shares of energy for nutrients were close to recommendations except for saturated fat (13.9 vs. 10% of energy) and carbohydrates (51.5 vs. 55-60% of energy). The mean calcium intake (1117 mg day(-1)) was above the recommendation, while the vitamin D intake (3.1 microg day(-1)) of 88% of the girls was below the recommendation. CONCLUSIONS: The diet quality of early pubertal girls is close to the recommendations and has improved with respect to fat compared with the 1980s. Consumption of milk products is high although the consumption of non-milk drinks has increased. We found a subgroup of girls who compensate their low milk product consumption with a higher consumption of non-milk drinks. Following a dairy-restricted diet is the main reason for low consumption of milk products.

Teenage girls and elderly women living in northern Europe have low winter vitamin D status.

OBJECTIVE: To determine the vitamin D status (serum 25-hydroxyvitamin D; S-25OHD) in adolescent girls and elderly community-dwelling women living in four countries of northern Europe and to explain differences in S-25OHD concentrations between and within the countries. DESIGN: A cross-sectional observational study conducted in a standardised way during February-March. S-25OHD was analysed by high-performance liquid chromatography. Vitamin D and calcium intake was calculated using a standardised food composition database. SETTING: Denmark, Finland, Ireland, and Poland. SUBJECTS: A total of 199 girls (mean (s.d.) age 12.6 (0.5) y) and 221 women (mean (s.d.) age 71.8 (1.4) y). RESULTS: The median (inter quartiles) concentration of S-25OHD was 29.4 (20.3, 38.3) nmol/l for the girls and 40.7 (28.0, 54.2) nmol/l for the women. S-25OHD below 25 nmol/l was found in 37% of the girls and 17% of the women, and S-25OHD below 50 nmol/l was found in 92% of the girls and 37% of the women. Positive significant determinants for S-25OHD in girls were use of vitamin D supplements, and in women sun habits, dietary vitamin D intake, use of vitamin D and calcium supplements. Body mass index and smoking were negative determinants in women. For women predictors could explain the differences between countries (P(country) = 0.09, R(2) = 0.39), but for girls the difference remained significant even after including predictors (P(country) = 0.03, R(2) = 0.15). CONCLUSION: Vitamin D status is low in northern Europe during winter. More than one-third of the adolescent girls have vitamin D status below 25 nmol/l and almost all are below 50 nmol/l. Two-thirds of the elderly community-dwelling women have vitamin D status below 50 nmol/l. Use of vitamin D supplements is a significant positive determinant for S-25OHD for both girls and women (P = 0.001). SPONSORSHIP: The European Fifth Framework Programme (Contract No. QLK1-CT-2000-00623).

A 7-week reduction in salt intake does not contribute to markers of bone metabolism in young healthy subjects.

BACKGROUND: Sodium intake increases urinary calcium excretion and may thus lead to negative calcium balance and bone loss. OBJECTIVE: We hypothesised that reducing sodium intake would reduce urinary calcium excretion and have a beneficial influence in bone metabolism. DESIGN: A total of 29 subjects, 14 males and 15 females, were divided into two study groups. One group (low-sodium group (LS)) reduced sodium intake for 7 weeks by substituting low-salt alternatives for the most important dietary sources of sodium. The other group, serving as a control group (C), was given the same food items in the form of normally salted alternatives. Fasting serum samples as well as 24-h urine samples were obtained in the beginning and at the end of the study. Urinary sodium, urinary calcium, urinary creatinine, serum calcium, serum phosphate, serum creatinine, serum parathyroid hormone (s-PTH), serum C-terminal telopeptides of Type-I collagen and serum bone alkaline phosphatase (s-B-ALP) were analysed. RESULTS: The LS group showed a significant decline (P = 0.001) in urinary sodium/creatinine ratio without a significant effect on urinary calcium/creatinine ratio. In the LS group, s-PTH increased (P = 0.03). The C group showed an increase in s-PTH (P = 0.05) and in s-B-ALP, but no differences were observed between the study groups in the changes of serum markers of calcium and bone metabolism. CONCLUSIONS: We have shown that reducing the sodium intake of young, healthy people with adequate calcium intake over a 7-week period does not affect the markers of bone metabolism.