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Background/objectives: This study investigates the predictors of serum cobalamin concentrations in community-dwelling older adults and the relationship between serum cobalamin and plasma homocysteine. Subjects/methods: Serum cobalamin and plasma homocysteine were measured by SimulTRAC-SNB radio assay and HPLC, respectively. Linear multiple regression analyses were performed with cross-sectional data of 352 participants aged 60–90 years to examine (1) the predictors of serum cobalamin and (2) the association between cobalamin and homocysteine status. Age, sex, body composition, diet, supplement use, smoking, serum folate, serum pyridoxal 5´-phosphate, serum creatinine, and selected diseases were considered as potential predicting/confounding factors. Results: Median values of serum cobalamin, plasma homocysteine, and dietary cobalamin intake were 256 pmol/L, 9.7 µmol/L, and 5.7 µg/day, respectively. In multiple regression analysis, cobalamin intake, sex, body composition, serum creatinine and smoking did not predict serum cobalamin (all P> 0.05). In contrast, age (β= 0.111, P= 0.031), serum folate (β= 0.410, P< 0.001) and diagnosis of chronic inflammatory bowel disease (IBD) (β= 0.101, P= 0.037) were positively and cancer diagnosis (β= −0.142, P= 0.003) was negatively associated with serum cobalamin. The model explained 23% of the variability of serum cobalamin. After exclusion of subjects with IBD/cancer diagnosis and/or vitamin B/multi-vitamin supplementation, only serum folate remained as positive predictor of serum cobalamin (β= 0.407, P< 0.001). Serum cobalamin was positively associated with inverse-transformed plasma homocysteine before (β= 0.298, P< 0.001) and after (β= 0.199, P< 0.001) multiple adjustments. Conclusions: Serum folate but not cobalamin intake or age proves to be a main predictor of cobalamin status. Nevertheless, independent of serum folate and other potential confounders, serum cobalamin is inversely associated with plasma homocysteine.

Dietary reference values for food energy for population groups are set at the level of average energy requirement without a safety margin to avoid any risk of inadequate energy intake. Average energy requirements and hence reference values for energy can be determined from either energy intake data or energy expenditure. In this article, the present reference values for energy of 12 countries, the FAO/WHO/UNU and the Scientific Committee on Food (SCF/EC) are compared regarding the level of their standards and underlying concepts. Methods for estimating energy requirements of different population groups and data sources for reference values for energy are summarized. Furthermore, reference values for energy for males and females of all ages are presented in separate graphs. The comparison of national standards illustrates that the level of reference values for energy for individual countries is dependent on variables such as methodology, data sources, allowances for physical activity, reference body weight, and age range. Standards for adolescents and elderly persons reveal that differences in reference values are most apparent in population groups for which only limited data on energy requirements are available. Although it is not possible to evaluate the adequacy of reference values for energy by comparing data of different countries, many differences in the level of reference values can be explained on the basis of underlying concepts. Richtwerte zur Zufuhr an Energie für Bevölkerungsgruppen werden in Höhe des durchschnittlichen Energiebedarfs ohne Sicherheitszuschläge festgelegt. Dadurch soll das Risiko einer unangemessenen Energiezufuhr minimiert werden. Der durchschnittliche Energiebedarf und somit die Richtwerte zur Energiezufuhr können über Daten zur Energiezufuhr oder über die Bestimmung des Energieverbrauchs ermittelt werden. Im vorliegenden Artikel werden die aktuellen Richtwerte zur Energiezufuhr von insgesamt 12 Ländern, der FAO/WHO/UNU und dem wissenschaftlichen Lebensmittelausschuß der Europäischen Union (SCF/EC) hinsichtlich ihrer Höhe und zugrunde liegenden Konzepten gegenübergestellt. Die Methoden zur Schätzung des Energiebedarfs für unterschiedliche Bevölkerungsgruppen und die Datenbasis für die Richtwerte zur Energiezufuhr werden zusammengefaßt. Darüber hinaus werden die Richtwerte zur wünschenswerten Zufuhr an Energie für Frauen und Männer aller Altersstufen graphisch dargestellt. Der Vergleich der nationalen Richtwerte zur Energiezufuhr verdeutlicht, daß die Höhe abhängig ist von Faktoren wie der methodischen Vorgehensweise, der Datengrundlage, dem verwendeten Referenzkörpergewicht, der Intensität der körperlichen Aktivität und der Alterseinteilung. Richtwerte für Jugendliche und ältere Menschen zeigen, daß Unterschiede in der Höhe der Richtwerte sich am deutlichsten bei Bevölkerungsgruppen darstellen, für welche nur unzureichendes Datenmaterial zum Energiebedarf verfügbar ist. Obwohl es nicht möglich ist, die Angemessenheit von Richtwerten zur wünschenswerten Energiezufuhr anhand eines Vergleichs der Daten unterschiedlicher Länder zu beurteilen, können Unterschiede in der Höhe der Richtwerte auf der Basis der zugrunde liegenden Konzepte erklärt werden.

BackgroundElderly subjects are at risk of insufficient vitamin D status mainly because of diminished capacity for cutaneous vitamin D synthesis. In cases of insufficient endogenous production, vitamin D status depends on vitamin D intake.ObjectiveThe purpose of this study is to identify the main food sources of vitamin D in elderly subjects and to analyse whether contributing food sources differ by sex, age, vitamin D status, body mass index (BMI), or household income. In addition, we analysed the factors that influence dietary vitamin D intake in the elderly.Design and subjectsThis is a cross-sectional study in 235 independently living German elderly aged 66–96 years (BMI=27±4 kg/m2). Vitamin D intake was assessed by a 3-day estimated dietary record.ResultsThe main sources of dietary vitamin D were fish/fish products followed by eggs, fats/oils, bread/bakery products, and milk/dairy products. Differences in contributing food groups by sex, age, vitamin D status, and BMI were not found. Fish contributed more to vitamin D intake in subjects with a household income of <1,500 €/month compared to subjects with higher income. In multiple regression analysis, fat intake and frequency of fish consumption were positive determinants of dietary vitamin D intake, whereas household income and percentage total body fat negatively affected vitamin D intake. Other parameters, including age, sex, physical activity, smoking, intake of energy, milk, eggs and alcohol, showed no significant association with vitamin D intake.ConclusionLow habitual dietary vitamin D intake does not affect vitamin D status in summer, and fish is the major contributor to vitamin D intake independent of sex, age, vitamin D status, BMI, and the income of subjects.