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Food and nutrition scientists, nowadays, need to manage an increasing amount of data regarding food composition, food consumption and Total Diet Studies (TDS). The corresponding datasets can contain information about several thousand different foods, in different versions from different studies. FoodCASE is a system that has been developed to manage these different datasets. It also support flexible means of linking between datasets and generally provide support for the different processes involved in the acquisition, management and processing of data. In this paper, the most important concepts to implement existing guidelines and standards for proper food data management are presented, as well as different use cases of data import and proofs of concepts demonstrating the ability to manage data in FoodCASE.

An efficient and robust method to measure vitamin D (25-hydroxy vitamin D3(25(OH)D3) and 25-hydroxy vitamin D2in dried blood spots (DBS) has been developed and applied in the pan-European multi-centre, internet-based, personalised nutrition intervention study Food4Me. The method includes calibration with blood containing endogenous 25(OH)D3, spotted as DBS and corrected for haematocrit content. The methodology was validated following international standards. The performance characteristics did not reach those of the current gold standard liquid chromatography-MS/MS in plasma for all parameters, but were found to be very suitable for status-level determination under field conditions. DBS sample quality was very high, and 3778 measurements of 25(OH)D3were obtained from 1465 participants. The study centre and the season within the study centre were very good predictors of 25(OH)D3levels (P3level on 20 January and a maximum on 21 July. The seasonal amplitude varied from centre to centre. The largest difference between winter and summer levels was found in Germany and the smallest in Poland. The model was cross-validated to determine the consistency of the predictions and the performance of the DBS method. The Pearson’s correlation between the measured values and the predicted values wasr0·65, and thesdof their differences was 21·2 nmol/l. This includes the analytical variation and the biological variation within subjects. Overall, DBS obtained by unsupervised sampling of the participants at home was a viable methodology for obtaining vitamin D status information in a large nutritional study.

The greatest burden of ill-health for adults in most societies relates to disorders of the cardiovascular system and to cancers [1]. These diseases are caused by lifestyle choices in which poor diet and relatively low levels of activity play a major role [1]. There is a large body of literature which shows that environmental exposures, including nutrition, play a significant role in the etiology of the disease, but there is variable susceptibility amongst individuals exposed to seemingly similar risk factors or environments. Cancer is a condition which results from a derangement in the cellular processes which regulate cell division, terminal differentiation and apoptosis, with damage to the genetic material of the cell being central. Exposures which lead to these derangements usually precede the appearance of the clinical disease by a prolonged period of time, often several decades [2]. While gene mutation has a role in the etiology of cancer, there is increasing evidence showing that epigenetic processes such as DNA methylation and covalent modification to histones are also involved [3]. Epigenetic changes of this kind represent potential for altered gene activity, and hence cellular dysregulation. However, the underlying propensity may only be manifest when the gene is exposed to an appropriate environmental signal with the direction of the response and nature of the cellular dysregulation a function of the specific epigenetic change [4, 5]. It has been known for many years that exposure of the individual to nutritional and other environmental challenges during critical periods of early development can markedly affect later size, shape, structure, function and behavior. However, Barker et al. [6] were the first to provide clear evidence that there might also be a direct link between early nutritional exposure and risk of chronic disease, building the evidence that is supportive of a causal association [6, 7]. In this they have refined a new conceptual approach to the way in which we consider the evolution of this group of diseases based upon a new developmental model, the so called ‘fetal origins hypothesis’. Based initially on ecological observations and later on retrospective cohort studies, there is now a considerable body of epidemiological and experimental data that supports the hypothesis. In the earlier observations, the size and shape of the baby at birth was shown to be related to the risk during adult life of coronary heart disease, hypertension, stroke, type 2 diabetes, obesity and some cancers [6]. These relations were shown to be graded across the usual range of birth weights seen in the population and not a special feature of very high or very low birth weight, indicating that they might be a consequence of the usual range of exposure found within a population [4, 7]. The results have been reproduced across a number of populations, and although there may be some debate around the details, the general principal appears to apply widely [4, 6, 7].

This paper describes a rapid analysis of free amino acid levels in capillary blood samples using a modified HPLC system. Capillary whole blood (25 microliters) is dried on a filter paper, extracted and the equivalent of 0.25 microliter of the initial blood sample is used for each amino acid analysis. Nineteen free amino acid levels are determined with a reproducibility of better than +/- 10% for the entire procedure of sampling, preparation and analysis, with the exception of ornithine (+/- 19%) and lysine (+/- 12%). Cystine and proline cannot easily be determined by this method. Alanine, tyrosine, methionine, valine, phenylalanine, isoleucine and leucine concentrations on the filter paper are unaltered after 1, 2 and 21 wk. Storage at room temperature should not be for longer than 2 wk, but storage at +4 degrees C, -18 degrees C and -70 degrees C is acceptable for 21 wk. This new micromethod seems to be a practical and reliable tool. Because of its simplicity and, above all, the need for a minimal amount of capillary blood, it is a valid means for the routine monitoring of amino acid profiles in sick preterm infants on different protein regimens. The sampling and storage methods are also examples of 'appropriate technology' for field studies of nutritional adequacy in population samples derived from infants. This is because centrifugation is not necessary and the fact that the relevant amino acids on the dried filter paper samples display high stability.

Nutritional status is a critical element of many aspects of animal ecology, but has proven difficult to measure non-invasively in studies of free-ranging animals. Urinary C-peptide of insulin (UCP), a small polypeptide cleaved in an equimolar ratio from proinsulin when the body converts it to insulin, offers great promise in this regard, and recent studies of several non-human primate species have utilized it with encouraging results. Despite this, there are a number of unresolved issues related to the collection, processing, storage and transport of samples. These include: contamination of samples on collection (most commonly by dirt or faeces), short-term storage before returning to a field station, differences in processing and long-term storage methods (blotting onto filter paper, freezing, lyophilizing), and for frozen samples, transportation while keeping samples frozen. Such issues have been investigated for urine samples in particular with respect to their effects on steroid hormone metabolites, but there has been little investigation of their effects on UCP measurement. We collected samples from captive macaques, and undertook a series of experiments where we systematically manipulated samples and tested the effects on subsequent UCP measurements. We show that contamination of urine samples by faeces led to a decrease in UCP levels by .90%, but that contamination with dirt did not have substantial effects. Short-term storage (up to 12 hours) of samples on ice did not affect UCP levels significantly, but medium-term storage (up to 78 hours) did. Freezing and lyophilization for long-term storage did not affect UCP levels, but blotting onto filter paper did. A transportation simulation showed that transporting frozen samples packed in ice and insulated should be acceptable, but only if it can be completed within a period of a few days and if freeze-thaw can be avoided. We use our data to make practical recommendations for fieldworkers. peerReviewed