This dataset contains the underlying research data for the paper: Merz, B.; Frommherz, L.; Rist, M.J.; Kulling, S.E.; Bub, A.; Watzl, B. Dietary Pattern and Plasma BCAA-Variations in Healthy Men and Women—Results from the KarMeN Study. Nutrients 2018, 10, 623. The tab-delimeted data file contains information of participants from the Karlsruhe Metabolomics and Nutrition (KarMeN) Study including descriptive metadata, plasma amino acid concentrations assessed via liquid chromatography–mass spectrometry, information on current dietary intake (food group level) assessed via 24h recall and information on habitual dietary intake (food group level and selected macronutrients) calculated with the NCI method. The dataset also includes an annotation file that is providing additional information such as unit, decoding of used abbreviations and a description of the included food groups.

Besides the adverse health effects of a low folate intake, the risks of high intakes of folic acid have moved into the focus. The aim of this study was to investigate the potential range of folate and folic acid intake of the German population under consideration of different fortification scenarios.

Folic acid (FA) concentrations of nine fortified vitamin juices were determined with the aim to study the FA degradation and to investigate the deviation from the declared label value. The juices were received shortly after bottling and were analyzed monthly during controlled storage conditions (light and dark) over one year. The analyses were performed by HPLC-MS/MS, which included a fast "dilute and shoot" sample preparation. Average decreases in FA concentration of 46% were observed after one year. Fresh juices (shortly after bottling) showed the highest deviations from the declared label value (up to+89%). Label values did not reflect the actual concentration of FA in these products, making it difficult to determine the intake of this vitamin.