Blood Concentrations Of Vitamin Research Articles

Analysis of published and clinical sample data to develop new ranges of liver and blood concentrations of vitamin A for diagnosis of vitamin A deficiency in cattle

In cattle, liver stores of vitamin A (VA) maintain blood VA concentrations until liver supplies are nearly exhausted, pro­viding VA to tissues during insufficient dietary intake. There­fore, normal blood levels do not indicate adequate VA, but low blood levels indicate a deficiency. We hypothesized that previous diagnostic criteria for VA deficiency needed updating and that blood levels of VA could be used as indicators of liver VA deficiency. We performed multiple regressions of paired blood and liver sample data from published experimental and field case reports of VA deficiency in cattle to demonstrate this. We fitted various models using data from unpaired clini­cal samples submitted to the Iowa State University Diagnostic Laboratory by comparing fractiles of liver and plasma/serum samples. Using these relationships, we propose new ranges for severely deficient, deficient, marginal and adequate, and we also propose that blood samples alone can be used to di­agnose deficiency in the presence of clinical signs of VA defi­ciency. Veterinary diagnostic laboratories can use this infor­mation to better estimate serum and liver VA concentrations for unpaired data and recommend to cattle practitioners the status of VA in their herds.

Vitamin Status in Children with Cystic Fibrosis Transmembrane Conductance Regulator Gene Mutation.

The issue of vitamin metabolism in children with cystic fibrosis screen positive, inconclusive diagnosis (CFSPID) is not well known. The aim of this study was to determine the status of vitamins A, D, E, and C in the blood of a group of children with CFSPID. A total of 89 children were enrolled in the study (Me: 3.6 years, 52.8% boys), as follows: 28 with CFSPID, 31 with CF (cystic fibrosis), and 30 HC (healthy children). Their blood concentrations of vitamins A, D, E, and C, and their dietary intake of these vitamins were analysed in the study groups on the basis of a three-day food diary. The patients with CFSPID had significantly higher serum vitamin D (p = 0.01) and E (p = 0.04) concentrations, compared to the children with CF. None of the children with CFSPID revealed vitamin A or E deficiencies. Patients with CF had been consuming significantly higher vitamin D and E amounts (p = 0.01). The vitamin concentrations did not depend either on the pancreatic/liver function or on anthropometric parameters. In total, 32.14% of patients with CF did not cover the baseline recommended calorie intake, and 53.6% and 36% did not take the recommended vitamin E and vitamin A intake, respectively. Children with CF and CFSPID did not fully cover the dietary recommendations for vitamin supply, but vitamin deficiency was found only in CF.

Antioxidant Supplementation Protects Elite Athlete Muscle Integrity During Submaximal Training.

To determine (1)the effect of a 40-minute steady-state run on muscle membrane integrity of elite athletes as reflected by serum creatine kinase (CK), (2)whether antioxidant supplementation (AS) with vitamins E and C has a protective effect, and (3)if a minimal blood concentration of vitamin E or C is required for any such protection. Fifteen elite-level endurance athletes (V˙O2max=71.5±1.2 mL·kg-1 min-1) were randomly assigned to 6weeks AS (1000IU·d-1 natural vitamin E and 1000mg·d-1 vitamin C) or placebo. Using a double-blind crossover design and 4-week washout period, each treatment was followed by a 40-minute steady-state run at 3mM blood lactate. Blood samples before and 0 and 24hours after the run were assayed for serum and red cell α-tocopherol (α-TOH), serum ascorbate, and CK. The AS produced a 2.5-fold, well-correlated (r = .84) increase in serum and red cell α-TOH (P < .001) that attenuated the increase in postrun CK (P = .01). There was no change in serum ascorbate with AS and no relationship with CK (P > .1). Curvilinear regression revealed some evidence that a critical level of serum α-TOH in the vicinity of 12mg·L-1 was required to attenuate CK efflux, a level only achieved with AS. The muscle membrane integrity of elite-level athletes is compromised even during steady-state running of moderate intensity and duration. The AS provided a protective effect, with evidence that a serum α-TOH concentration of around 12mg·L-1 is required.

Diet-Derived Antioxidants Do Not Decrease Risk of Ischemic Stroke: A Mendelian Randomization Study in 1Million People.

BackgroundDietary intake and blood concentrations of vitamins E and C, lycopene, and carotenoids have been associated with a lower risk of incident (ischemic) stroke. However, causality cannot be inferred from these associations. Here, we investigated causality by analyzing the associations between genetically influenced antioxidant levels in blood and ischemic stroke using Mendelian randomization.Methods and ResultsFor each circulating antioxidant (vitamins E and C, lycopene, β‐carotene, and retinol), which were assessed as either absolute blood levels and/or high‐throughput metabolite levels, independent genetic instrumental variables were selected from earlier genome‐wide association studies (P<5×10−8). We used summary statistics for single‐nucleotide polymorphisms–stroke associations from 3 European‐ancestry cohorts (cases/controls): MEGASTROKE (60 341/454 450), UK Biobank (2404/368 771), and the FinnGen study (8046/164 286). Mendelian randomization analyses were performed on each exposure per outcome cohort using inverse variance–weighted analyses and subsequently meta‐analyzed. In a combined sample of 1 058 298 individuals (70 791 cases), none of the genetically influenced absolute antioxidants or antioxidant metabolite concentrations were causally associated with a lower risk of ischemic stroke. For absolute antioxidants levels, the odds ratios (ORs) ranged between 0.94 (95% CI, 0.85–1.05) for vitamin C and 1.04 (95% CI, 0.99–1.08) for lycopene. For metabolites, ORs ranged between 1.01 (95% CI, 0.98–1.03) for retinol and 1.12 (95% CI, 0.88–1.42) for vitamin E.ConclusionsThis study did not provide evidence for a causal association between dietary‐derived antioxidant levels and ischemic stroke. Therefore, antioxidant supplements to increase circulating levels are unlikely to be of clinical benefit to prevent ischemic stroke.

Vitamins as Possible Cancer Biomarkers: Significance and Limitations.

The Western-style diet, which is common in developed countries and spreading into developing countries, is unbalanced in many respects. For instance, micronutrients (vitamins A, B complex, C, D, E, and K plus iron, zinc, selenium, and iodine) are generally depleted in Western food (causing what is known as ‘hidden hunger’), whereas some others (such as phosphorus) are added beyond the daily allowance. This imbalance in micronutrients can induce cellular damage that can increase the risk of cancer. Interestingly, there is a large body of evidence suggesting a strong correlation between vitamin intake as well as vitamin blood concentrations with the occurrence of certain types of cancer. The direction of association between the concentration of a given vitamin and cancer risk is tumor specific. The present review summarized the literature regarding vitamins and cancer risk to assess whether these could be used as diagnostic or prognostic markers, thus confirming their potential as biomarkers. Despite many studies that highlight the importance of monitoring vitamin blood or tissue concentrations in cancer patients and demonstrate the link between vitamin intake and cancer risk, there is still an urgent need for more data to assess the effectiveness of vitamins as biomarkers in the context of cancer. Therefore, this review aims to provide a solid basis to support further studies on this promising topic.

Vitamin D role in endothelial dysfunction development in patients with polycystic ovarian syndrome

Background. The study was aimed to determine the correlation between the blood concentration of vitamin D and factors that influence the function of the endothelium and the hemodynamic of gonads in women with polycystic ovary syndrome (PCOS). Material and methods. Sixty women aged from 18 to 26 years were examined: 30 women with a diagnosis of PCOS and 30 healthy women. The blood serum concentration of vitamin D, C-reactive protein (CRP), interleukin-6 (IL-6), homocysteine (Hcy), nitrites/nitrates (NOx), and arginine were investigated. Maximum systolic velocity (Vmax), resistance index (RI), and pulsatility index (PI) were measured with Doppler ultrasound. Cholecalciferol was used in a dose of 4000 IU per day for 12 weeks for the correction of deficiency of vitamin D. Results. The patients with PCOS were found to have a lower (Р&lt;0.001) average vitamin D than healthy women. The reduction of vitamin D concentration was combined with an increase (P&lt;0.001) in the average concentration of NOx and a decrease in arginine. It was found a positive association between vitamin D and arginine (r=0.391; P&lt;0.05), between NOx and CRP (r=0.432; P&lt;0.02), IL-6 (r=0.476; P&lt;0.01), Vmax (r=0.383; P&lt;0.05), RI (r=0.369; P&lt;0.05), PI (r=0.380; P&lt;0.05) and reverse correlation with arginine (r=–0.375; P&lt;0.05). It was not found an association between NOx and vitamin D (r=0.207; P&gt;0.05), Hcy (r=0.176; P&gt;0.05); between vitamin D and Vmax (r=0.231; P&gt;0.05), RI (r=0.201; P&gt;0.05), PI (r=0.181; P&gt;0.05). The therapy of cholecalciferol level was accompanied by an increase (P&lt;0.001) in concentrations of vitamin D, arginine (P&lt;0.05) and a decrease in NOx (P&lt;0.02), IL-6 (P&lt;0.05), SRP (P&lt;0.001), Hcy (P&lt;0.001), Vmax (P&lt;0.001), RI (P&lt;0.001), PI (P&lt;0.01), quantity of antral follicles (P&lt;0.001), and the growth of follicles (P&lt;0.001). However, none of the studied indicators reached the indicators in healthy women. Conclusions. The deficiency of vitamin D is associated with increased markers of chronic inflammation, homocysteine, nitrate/nitrites, reduced concentration of arginine that provokes the development of endothelium dysfunction and, therefore, the hemodynamics disorders and folliculogenesis in the ovary.

The Isoform GC1f of the Vitamin D Binding Protein Is Associated with Bronchiectasis Severity.

Vitamin D modulates immune responses and its deficiency has been observed in more than 60% of bronchiectasis patients. Vitamin D binding protein (DBP) is coded by the GC gene, is involved in the transport of vitamin D, and includes a number of isoforms based on single nucleotide polymorphisms (SNPs) in the coding region at rs7041 and rs4855. We evaluated the possible clinical impact of DBP polymorphisms and isoforms in an observational, cross-sectional study conducted in 116 bronchiectasis patients, who were genetically characterized for rs4588 and rs7041 SNPs. Results showed that the GC1f isoform (rs7041/rs4588 A/G) correlated with a more severe disease (18.9% vs. 6.3%, p = 0.038), a higher incidence of chronic infections (63.6% vs. 42%, p = 0.041), and a lower BACI score (0.0 (0.0, 2.5) vs. 3.0 (0.0, 3.0), p = 0.035). Moreover, blood concentration of vitamin D was higher in patients carrying GC1s (median (IQR): 20.5 (14.3, 29.7 vs. 15.8 (7.6, 22.4), p = 0.037)). Patients carrying GC1f isoform have a more severe disease, more chronic infections and lower asthmatic comorbidity in comparison to those without the GC1f isoform. Presence of the GC1s isoform (rs7041/rs4588 C/G) seems to be associated to a milder clinical phenotype with increased vitamin D levels and lower comorbidities score.

Dietary-derived antioxidants do not decrease the risk of ischemic stroke: A Mendelian randomization study

Background and Aims: In observational studies, dietary intake, as dietary components or supplements, and blood concentrations of vitamin E, C, lycopene and carotenoids were associated with a lower risk of ischemic stroke. However, these studies were prone to residual confounding and reverse causation, and thereby limit the ability for causal inference. We investigated the associations between genetically-determined antioxidant concentrations and ischemic stroke using Mendelian Randomization.

Vitamin E and beta-carotene status of dairy cows: a survey of plasma levels and supplementation practices

Culling rate in dairy cattle has increased considerably, thereby reducing cowś longevity and raising sustainability concerns worldwide. In the last decades, feeding systems have changed towards larger inclusion of preserved forages and reduced fresh herbage, which may limit vitamin E and beta-carotene dietary supply to dairy cows. Because of higher oxidative stress, engendered by greater milk production of modern genetics, the requirement for these nutrients is increased. Therefore, this study aimed to assess the current status of vitamin E and beta-carotene of commercial dairy cows. Blood vitamin E and beta-carotene concentrations were measured in 2 467 dairy cows from 127 farms in Belgium, Germany, Iberia and The Netherlands, that were visited once. Five cows were randomly selected per lactation stage per farm: Dry (between 30 and 1 day(s) before calving), Very-early (from calving until 15 days in milk (DIM)), Early (between 16 and 119 DIM), and Mid-late (from 120 DIM onwards). In addition, a survey was conducted to retrieve data on vitamin E and beta-carotene supplementation and feeding practices. Vitamin E and beta-carotene blood concentrations dropped considerably around calving. Among all surveyed cows, more than 75 and 44% were deficient in vitamin E and beta-carotene (i.e., blood concentration below 3.0 and 3.5 mg/l, respectively). Of the Very-early group, more than 97 and 78% of the cows were deficient in vitamin E and beta-carotene, respectively, with respective blood concentrations of 1.15 and 2.71 mg/l, which was significantly lower than the other lactation stages. Vitamin E and beta-carotene blood concentrations, as well as their supplementation levels, significantly varied among countries. Vitamin E and beta-carotene blood concentrations were positively related to the total estimated daily intakes of vitamin E and beta-carotene. Therefore, blood concentrations of vitamin E and beta-carotene depend on their respective level of intake, which is generally below recommendations and varies greatly between countries. Supplementation could contribute to provide cows with adequate amounts of vitamin E and beta-carotene all along the lactation, to ensure their lifetime performance and improve their fertility.

Determination of Blood Micromineral and Fat-Soluble Vitamin Values for White-tailed Deer

Abstract The current National Academies of Sciences, Engineering, and Medicine (NASEM) for trace mineral and vitamin requirements for cervids are based on data collected from various small ruminant species. Lack of baseline requirements make diet formulation for high fenced, white-tailed deer (Odocoileis virginianus) herds particularly ambiguous. This study was to determine a baseline value for whole blood and serum micromineral and vitamin concentrations for white-tailed deer in an attempt to establish dietary requirements of trace minerals and vitamins. Open does (n = 226) were sampled using jugular venipuncture during fall breeding procedures. Captive-raised does housed at various high fenced ranches (n = 3) throughout Texas were used, each with unique management strategies. Blood samples were analyzed for micromineral levels (Co, Cu, Fe, Mn, Mo, Se, and Zn) and fat-soluble metabolites (vitamin A, vitamin E, and cholesterol). Age of the doe and ranch were used as main effects using the GLM procedure in. Sampled averages across all ranches were 6.26 ng/mL of Co, 1.05 µg/mL of Cu, 219.47 µg/mL of Fe, 4.40 ng/mL of Mn, 4.23 ng/mL of Mo, 172.32 ng/mL of Se, 0.54 µg/mL of Zn, 286.76 ng/mL of vitamin A, 1.80 µg/mL of vitamin E, and 79.27 of cholesterol. Micronutrient levels were not affected by age; however, least squared differences existed between the main effect ranch for Co (P &amp;lt; 0.01), Cu (P &amp;lt; 0.01), Fe (P &amp;lt; 0.01), Mo (P &amp;lt; 0.01), Mn (P &amp;lt; 0.01), Se (P &amp;lt; 0.01), Zn (P &amp;lt; 0.01), vitamin E (P &amp;lt; 0.01), and cholesterol (P = 0.038) in serum. There was an observed interaction of age and ranch for vitamin A (P = 0.038). Factors such as feed, forage, soil, genetics, and health management protocols could explain the broad range in values. The establishment of circulating blood micronutrient levels will serve as a baseline for future white-tailed deer nutrient requirement research and feed formulation.

Вітамін D: нові аспекти застосування, ефективні дози. Сучасний стан проблеми

Крім класичної ролі вітаміну D в підтримці нормального стану скелетно-м’язової системи, в останнє десятиліття отримані докази того, що знижені концентрації в сироватці крові 25(OH)D асоційовані з низкою позаскелетних захворювань (цукровий діабет, артеріальна гіпертензія, захворювання щитоподібної залози, вікове зниження пізнавальної здатності, порушення функцій імунної та репродуктивної систем й ін.). Запобігання розвитку цих захворювань досягається при значно більш високих концентраціях 25(OH)D в сироватці крові, ніж це необхідно для підтримки нормального стану кісткової тканини, регуляції абсорбції й підтримки гомеостазу кальцію. Для забезпечення концентрації циркулюючої форми вітамінуD— 25(OH)D в сироватці крові на рівні, що забезпечує оптимальне функціонування, необхідне більш високе споживання цього вітаміну. Знижена концентрація вітаміну D в крові (&lt; 30 нг/мл) відзначається у 92% дорослого населення України незалежно від пори року. Причинами дефіциту вітаміну D є низька ефективність його ендогенного синтезу в шкірі через недостатню інсоляцію та неадекватне надходження цього вітаміну з їжею. Завдяки періоду напіввиведення вітаміну D близько двох місяців, періодичне щотижневе або щомісячне споживання сукупних доз холекальциферолу дає змогу досягти тих самих значень у сироватці крові, як і щоденне споживання. В огляді літератури розглядається значення дефіциту та недостатності вітамінуD у порушеннях регуляції багатьох систем організму людини та розвитку різних патологічних станів, що обґрунтовує доцільність ширшого використання методів корекції статусу вітаміну D. Попри необхідність проведення масштабних рандомізованих клінічних випробувань для визначення схем використання препаратів вітаміну D, уже зараз не викликає сумніву той факт, що нормалізація рівня 25(ОН)D у сироватці крові потрібна на всіх вікових етапах онтогенезу.

B vitamin blood concentrations and one-carbon metabolism polymorphisms in a sample of Italian women and men attending a unit of transfusion medicine: a cross-sectional study

PurposeTo define blood status of folate, vitamin B12, vitamin B6, homocysteine, and major one-carbon metabolism-related polymorphisms in healthy, males and females blood donors, aged 18–65 years were evaluated. General characteristics and lifestyle factors were also investigated.MethodsAn explorative cross-sectional study design was used to evaluate a sample of blood donors attending the Unit of Transfusion Medicine of the Verona University Hospital, Italy. From April 2016 to May 2018, 499 subjects were enrolled (255 men, 244 women of whom 155 of childbearing age). Major clinical characteristics including lifestyle and dietary habits, B vitamins and homocysteine were analyzed. The MTHFR 677 C>T, cSHMT 1420 C>T, DHFR 19 bp ins/del, RFC1 80 G>A polymorphisms were also determined.ResultsMean plasma concentrations of folate, vitamin B12, vitamin B6 and homocysteine were 14.2 nmol/L (95% CI 13.7–14.8), 271.9 pmol/L (95% CI 262.6–281.5), 51.0 nmol/L (95% CI 48.7–53.4) and 13.5 µmol/L (95% CI 13.1–14.0), respectively. Plasma folate, was adequate (> 15 nmol/L) in 44.7% of all subjects, 39.0% of males and 42.5% of women < 45 years. Similarly, vitamin B12 was adequate (> 350 pmol/L) in 25.1% of all subjects and in 20.3% of men ≥ 45 years. The rare allele frequencies were 0.21 for MTHFR 677TT, 0.11 for cSHMT 1420TT, 0.18 for DHFR 19 bp del/del, 0.20 for RFC1 80AA, and a gene–nutrient interaction was confirmed for folate concentrations according to MTHFR 677C>T and DHFR 19 bp del/del.ConclusionAn Italian sample of healthy blood donors shows that an adequate concentration of plasma folate and vitamin B12 is reached only in a limited percentage of subjects, thus encouraging consideration for specific public health strategies.

A new measure of health motivation influencing food choices and its association with food intakes and nutritional biomarkers in European adolescents.

To develop a scale to assess health motivation influencing food choices and to explore its performance in the associations with food intakes and nutritional biomarkers. Psychometric study using cross-sectional self-report questionnaires and nutritional biomarkers. Multi-centre investigation conducted in ten European cities. 2954 adolescents who were included in the HELENA study and completed the Food Choices and Preferences (FCP) questionnaire. Nineteen out of 124 items of the FCP questionnaire were in the same dimension. Sixteen presented adequate parameters for the Scale of evaluatiOn of Food choIcEs (SOFIE). The scores were positively associated with the intakes of cereals, dairy products, meats and eggs, and fish, as well as with blood concentrations of vitamin C, β-carotene, n-3 fatty acids, cobalamin, holo-transcobalamin and folate; scores were negatively associated with the intake of alcohol. SOFIE can improve the assessment of motivation influencing food choices based on items with the best performance and is proposed as a new measure to health-related studies.

Blood concentrations of vitamins B1, B6, B12, C and D and folate in palliative care patients: Results of a cross-sectional study.

ObjectiveThe main purpose of palliative care is symptom relief. Frequently, the symptoms of patients requiring palliative care are the same as common symptoms of vitamin deficiency (e.g. pain, weakness, fatigue, depression). The study aim was to investigate whether patients in palliative care are vitamin deficient.MethodThis was a monocentre cross-sectional study. Patients attending the palliative care unit of a general hospital in Germany from October 2015 to April 2016 were examined for vitamin blood concentrations and symptoms. Data were analysed using univariate analysis and bivariate correlations.ResultsData were available from 31 patients. Vitamin D3 deficiency (<62.5 nmol/L) affected 93.5% of patients, vitamin B6 deficiency (<4.1 ng/mL) 48.4%, vitamin C deficiency (<4.5 mg/L) 45.2%, vitamin B1 deficiency (<35 µg/L) 25.8% and vitamin B12 deficiency (<193 pg/mL) 12.9%. There was a significant negative correlation between vitamin B1 ranges and pain (r = −0.384) and depression (r = −0.439) symptoms.ConclusionAll patients showed a deficiency in at least one of the measured vitamins; 68% had concurrent deficiencies in >1 vitamin. A follow-up study using validated questionnaires and a larger sample is needed to investigate the effects of targeted vitamin supplementation on quality of life and symptom burden.

Reproducibility and Validity of a Short Food Frequency Questionnaire for Dietary Assessment in Children Aged 7⁻9 Years in Spain.

The purpose of this study was to examine if the short semi-quantitative food frequency questionnaire (FFQ) is a reliable and valid tool to assess the diet of Spanish children aged 7–9 years. We collected data from 156 children of the birth cohort INMA (Infancia y Medio Ambiente (Environment and Childhood)). Children’s parents or care-givers completed a 46-item FFQ on two occasions over a 9–12-month period about the children’s diet. To explore the reproducibility of the FFQ, the nutrient and food group intake collected from the both FFQs were compared, while validity was examined by contrasting the nutrient values from the FFQs and the average of three 24-hour dietary recalls (24hDRs) taken in this period, and also with the concentration of several vitamins in the blood (carotenoids, vitamin D and α-tocopherol). Pearson and de-attenuated correlation coefficients were calculated. The average correlation coefficients for nutrient intake’s reproducibility was 0.41, ranging from 0.25 (calcium) to 0.65 (β-carotene), and for food group intake was 0.45, ranging from 0.18 (cereals) to 0.68 (sweetened beverages). Correlation coefficients slightly improved when we compared energy-adjusted intakes. The average correlation coefficients for validity against 24hDRs was 0.34 for energy-adjusted intakes, and 0.39 when de-attenuation coefficients were used. The validity coefficients against the blood concentrations of vitamins were 0.38 for β-cryptoxanthin, 0.26 for lycopene, 0,23 for α-carotene and 0.15 for β-carotene, all of them statistically significant (p < 0.05). This study suggests that our brief FFQ is a suitable tool for the dietary assessment of a wide range of nutrients and food groups in children 7–9 years, despite the low to moderate reproducibility and validity observed for some nutrients.

Maternal Supplementation with Antioxidant Vitamins in Sheep Results in Increased Transfer to the Fetus and Improvement of Fetal Antioxidant Status and Development.

Twinning and maternal nutritional restriction leads to fetal hypoxia, oxidative stress, and intrauterine growth restriction (IUGR) in near-term sheep pregnancies. Our aim was to determine the effect of oral supplementation of vitamins C and E in pregnant sheep on maternal and umbilical cord blood concentrations of vitamins C and E and the effects on fetal antioxidant status, growth, and placental efficiency. Sixteen single- and sixteen twin-bearing ewes, grazing natural Patagonian prairies, were selected after transrectal ultrasound at day 30 after mating. Half of ewes from each pregnancy rank were supplemented daily with vitamins C and E, administered orally, from 30 to 140 days of gestation, when maternal jugular and fetal venous cord blood samples were obtained during cesarean section. Fetuses were weighed and sexed. Placental weight in each fetus was also obtained. Blood plasma was harvested for measurements of maternal and fetal vitamins concentration and fetal antioxidant capacity. Maternal administration of vitamin C and E was associated with increased fetal cord levels of both vitamins, improved antioxidant status, and enhanced fetal growth in both singleton and twin pregnancies associated with increased placental efficiency. These results highlight the potential of vitamin C and E supplementation to reduce the impact of IUGR in both livestock and humans.

Blood concentrations and renal clearance of water-soluble vitamins in outpatients with ulcerative colitis.

Few studies have investigated the association between dietary intake and blood concentrations of water-soluble vitamins in patients with ulcerative colitis (UC). In the present study, vitamin concentrations were measured in the blood and urinary excretion of 23 outpatients with UC and compared against a control group of 20 healthy participants. A weighed food record procedure was used to ensure controlled macronutrient and vitamin intakes of the UC cohort. Individuals in the control group were given a semi-purified diet for 8 days prior to assessment. Multiple linear regression analysis was used to identify important differences in vitamin concentrations, independent of sex, age and other confounding variables. The blood concentrations of vitamins B2, C, niacin and folate were markedly lower in the patients with UC than those in the control group, and the renal clearance of vitamins B1, B6, B12 and folate was notably higher in the UC cohort. It was concluded that vitamins B2, C, niacin and folate were at significantly lower concentrations in patients with UC following adjustment for coexisting factors. The lower levels of niacin may be partially due to impaired reabsorption. Chronic inflammation, common in patients with UC, with may contribute to the lower levels of other vitamins by rendering amino acid and carbohydrate metabolism into a hypermetabolic state. As the role of vitamins in metabolic activity is constant and pervasive, nutritional management including the application of water-soluble vitamins appears important for patients suffering from UC.

Measuring nutritional knowledge using Item Response Theory and its validity in European adolescents.

To analyse the Nutritional Knowledge Test (NKT) using Item Response Theory (ITR) analysis and to assess the construct validity of the Nutritional Knowledge Scale (NKTS) and its associations with adolescent food group consumption and nutritional biomarkers. Cross-sectional study. Multicentre investigation conducted in ten European cities.ParticipantsAdolescents aged 12·5-17·5 years (n 3215) who completed over 75 % of the NKT. Factor analysis indicated that the NKT can be analysed with a one-dimensional model. Eleven out of twenty-three items from the NKT presented adequate parameters and were selected to be included in the NKTS. Nutrition knowledge was positively associated with consumption of fruits, cereals, dairy products, pulses, meat and eggs, and fish, as well as with blood concentrations of vitamin C, β-carotene, n-3 fatty acids, holo-transcobalamin, cobalamin and folate; nutrition knowledge was negatively associated with intake of olives and avocado, alcohol and savoury snacks. The NKTS assessed nutritional knowledge adequately and it is proposed as a new tool to investigate this subject in future studies.

Dietary intake and blood concentrations of antioxidants and the risk of cardiovascular disease, total cancer, and all-cause mortality: a systematic review and dose-response meta-analysis of prospective studies

ABSTRACTBackgroundHigh dietary intake or blood concentrations (as biomarkers of dietary intake) of vitamin C, carotenoids, and vitamin E have been associated with reduced risk of cardiovascular disease, cancer, and mortality, but these associations have not been systematically assessed.ObjectiveWe conducted a systematic review and meta-analysis of prospective studies of dietary intake and blood concentrations of vitamin C, carotenoids, and vitamin E in relation to these outcomes.DesignWe searched PubMed and Embase up to 14 February 2018. Summary RRs and 95% CIs were calculated with the use of random-effects models.ResultsSixty-nine prospective studies (99 publications) were included. The summary RR per 100-mg/d increment of dietary vitamin C intake was 0.88 (95% CI: 0.79, 0.98, I2 = 65%, n = 11) for coronary heart disease, 0.92 (95% CI: 0.87, 0.98, I2 = 68%, n = 12) for stroke, 0.89 (95% CI: 0.85, 0.94, I2 = 27%, n = 10) for cardiovascular disease, 0.93 (95% CI: 0.87, 0.99, I2 = 46%, n = 8) for total cancer, and 0.89 (95% CI: 0.85, 0.94, I2 = 80%, n = 14) for all-cause mortality. Corresponding RRs per 50-μmol/L increase in blood concentrations of vitamin C were 0.74 (95% CI: 0.65, 0.83, I2 = 0%, n = 4), 0.70 (95% CI: 0.61, 0.81, I2 = 0%, n = 4), 0.76 (95% CI: 0.65, 0.87, I2 = 56%, n = 6), 0.74 (95% CI: 0.66, 0.82, I2 = 0%, n = 5), and 0.72 (95% CI: 0.66, 0.79, I2 = 0%, n = 8). Dietary intake and/or blood concentrations of carotenoids (total, β-carotene, α-carotene, β-cryptoxanthin, lycopene) and α-tocopherol, but not dietary vitamin E, were similarly inversely associated with coronary heart disease, stroke, cardiovascular disease, cancer, and/or all-cause mortality.ConclusionsHigher dietary intake and/or blood concentrations of vitamin C, carotenoids, and α-tocopherol (as markers of fruit and vegetable intake) were associated with reduced risk of cardiovascular disease, total cancer, and all-cause mortality. These results support recommendations to increase fruit and vegetable intake, but not antioxidant supplement use, for chronic disease prevention.

Indoor, outdoor, and night work and blood concentrations of vitamin D and parathyroid hormone.

Objectives The aim of this study was to examine blood concentrations of 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) among indoor, outdoor, permanent and rotating night workers and the association with hours spent outdoors on and off work days. Methods Blood samples were collected from 425 workers (162 indoor, 112 outdoor, 118 rotating night and 33 permanent night workers) throughout all seasons. Serum concentrations of 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) were analyzed by isotope dilution liquid chromatography-tandem mass spectrometry (LC MS/MS) and an automated immune analyzer, respectively. Personal light exposure levels were continuously recorded and used to estimate hours spent outdoors (all workers). Results Permanent night workers had 25.3% (95% CI 11.9-36.6) lower 25OHD concentration, 4.55 (95% CI 1.39-14.94) higher odds of vitamin D insufficiency (<50 nmol/L) and 14.5% [95% confidence interval (CI) 0.1-31.1] higher PTH concentration than indoor workers. Outdoor workers had similar 25OHD concentrations but 7.5% (95% CI -0.5-14.9) lower PTH concentration compared to indoor workers. Rotating night workers 25OHD and PTH concentrations did not differ from indoor workers. Concentration of 25OHD increased by 5.2% (95% CI 1.1-9.5) per hour spent outdoor at workdays in the summer. Conclusion Clinicians should be aware that vitamin D insufficiency may be more prevalent among permanent night workers and human resources should consider the positive effect of allowing workers to spend time outdoor during work hours.