Tamara Bucher

Ubiquitin-related modifier Urm1 acts as a sulphur carrier in thiolation of eukaryotic transfer RNA

Ubiquitin-like proteins (UBLs) can change protein function, localization or turnover by covalent attachment to lysine residues. Although UBLs achieve this conjugation through an intricate enzymatic cascade, their bacterial counterparts MoaD and ThiS function as sulphur carrier proteins. Here we show that Urm1p, the most ancient UBL, acts as a sulphur carrier in the process of eukaryotic transfer RNA (tRNA) modification, providing a possible evolutionary link between UBL and sulphur transfer. Moreover, we identify Uba4p, Ncs2p, Ncs6p and Yor251cp as components of this conserved pathway. Using in vitro assays, we show that Ncs6p binds to tRNA, whereas Uba4p first adenylates and then directly transfers sulphur onto Urm1p. Finally, functional analysis reveals that the thiolation function of Urm1p is critical to regulate cellular responses to nutrient starvation and oxidative stress conditions, most likely by increasing translation fidelity.

The Swiss iodized salt program provides adequate iodine for school children and pregnant women, but weaning infants not receiving iodine-containing complementary foods as well as their mothers are iodine deficient.

BACKGROUND If children and pregnant women in the population are iodine sufficient, it is generally assumed infants are also sufficient. But weaning infants may be at risk of iodine deficiency because iodized salt contributes little dietary iodine during this period. To fill this gap, iodine fortification of infant formula milk (IFM) and complementary foods (CF) is likely important. OBJECTIVES The objective of the study was to first confirm that Swiss school children and pregnant women remain iodine sufficient and then to assess iodine status in infancy and the relative contribution of breast milk and IFM/CF to their iodine intakes. METHODS We measured urinary iodine concentrations (UIC) in national cross-sectional samples of: 1) pregnant women (n=648); 2) school children (n=916); 3) infants at three time points: at 3-4 d after birth and at 6 and 12 months (n=875); and 4) breast-feeding mothers (n=507). We measured breast milk iodine concentrations in the mothers, assessed iodine sources in infant diets, and analyzed iodine content of commercial IFM/CFs (n=22) and salt samples from the school childrens households (n=266). RESULTS Median (m) UICs in pregnant women (162 μg/liter) and school children (120 μg/liter) were sufficient, and 80% of the household salt was adequately iodized (≥15 ppm). However, mUICs in infants not receiving IFM/CF were not sufficient: 1) mUIC in breast-fed infants (82 μg/liter) was lower than in non-breast-fed infants (105 μg/liter) (P<0.001) and 2) mUIC in breast-fed weaning infants not receiving IFM/CF (70 μg/liter) was lower than infants receiving IFM (109 μg/liter) (P<0.01). mUIC was low in lactating mothers (67 μg/liter) and median breast milk iodine concentration was 49 μg/kg. CONCLUSIONS In countries in which iodized salt programs supply sufficient iodine to older children and pregnant women, weaning infants, particularly those not receiving iodine-containing IFM, may be at risk of inadequate iodine intakes.

The influence of plate size on meal composition. Literature review and experiment.

Environmental factors, such as the size of containers, can influence our energy intake. Even though different sized food containers are often recommended to control portion sizes, the evidence to support this is contradictory. In the present study, we conducted a literature review and a controlled laboratory experiment to investigate whether plate size influences the composition of a meal and the total meal energy. The results of the review suggest that distraction factors, the type of container, the food-serving mode (self-service or being served) and the type of food offered all influenced the results observed in the various published studies. For the experiment in this study, eighty-three participants were individually invited to serve themselves a lunch from a buffet containing 55 replica food items. Either a standard size plate (27 cm) or a large plate (32 cm) was provided to the participants. The results of the experiment suggest that the plate size had no significant effect on the total energy of the meal (F(1,81) =0.782, P> .05). However, participants using a large plate served themselves significantly more vegetables (F(1,81) =4.786, P< .05), particularly vegetables generally eaten as side dishes (F(1,81) =6.804, P< .05). Therefore, reducing the plate size does not seem to be an appropriate intervention to reduce the total energy intake in order to promote weight loss. Rather, using a large plate might be a simple and inexpensive strategy to increase vegetable consumption.

Vegetable variety: an effective strategy to increase vegetable choice in children

OBJECTIVE Most children do not meet the recommended intake of vegetables. Variety was identified as a potential factor to increase childrens intake of these foods, as it was shown that variety was effective in improving meal composition in adults. Because younger children are suggested to be more responsive to internal satiation signals than to external food-related cues compared with adults, it is not clear whether variety is effective to improve meal composition in 7- to 10-year-old children. DESIGN Experiment. SETTING Children were assigned one of three different fake food buffets containing pasta, chicken, and either one vegetable (carrots or beans) or two vegetables (carrots and beans). The children were asked to serve themselves a meal that they would like to eat for lunch from the given selection. SUBJECTS One hundred children (fifty-two boys; mean age 8·8 (sd 1·1) years). RESULTS Children given the two-vegetable choice served themselves significantly more energy from vegetables (mean 64 (sd 51) kJ, 10·9 (sd 9·4) %) compared with children who were offered only either carrots (mean 37 (sd 25) kJ, 5·9 (sd 6·5) %) or beans (mean 38 (sd 34) kJ, 5·6 (sd 6·3) %). The total energy of the meal was not increased, indicating that children chose a more balanced lunch when offered more vegetables. CONCLUSIONS School-aged children are responsive to food-related cues and variety is effective in increasing their vegetable choice. Serving an assortment of vegetables in school cafeterias might be a simple and effective strategy to improve childrens nutrition.

The fake food buffet – a new method in nutrition behaviour research

Experimental research in behavioural nutrition is often limited by practical applicability. In the present study, we assess the reproducibility and validity of a new experimental method using food replicas. A total of fifty-seven people were invited on two separate occasions with an interval of 2 weeks to serve themselves a meal from a fake food buffet (FFB) containing replica carrots, beans, pasta and chicken. The external validity of the FFB was assessed in a second study by comparing meals served from replica foods (beans, pasta, chicken) with meals served from a corresponding real food buffet (RFB). For the second study, forty-eight participants were invited on two separate occasions; first to serve themselves a meal from the FFB or an RFB and 2 weeks later from the other buffet. The amounts of food items served and (theoretical) energy content were compared. Correlation coefficients between the amounts of fake foods served were 0·77 (95 % CI 0·68, 0·86) for chicken, 0·79 (95 % CI 0·68, 0·87) for carrots, 0·81 (95 % CI 0·69, 0·89) for beans and 0·89 (95 % CI 0·82, 0·93) for pasta. For the FFB meal and the RFB meal, the correlations ranged between 0·76 (95 % CI 0·73, 0·91) for chicken and 0·87 (95 % CI 0·77, 0·92) for beans. The theoretical energy of the fake meal was 132 kJ (32 kcal) lower compared to the energy of the real meal. Results suggest that the FFB can be a valuable tool for the experimental assessment of relative effects of environmental influences on portion sizes and food choice under well-controlled conditions.

What Are They Really Eating? A Review on New Approaches to Dietary Intake Assessment and Validation

PurposeAssessing food and nutrient intakes is critical to evolving our understanding of diet-disease relationships and the refinement of nutrition guidelines to support healthy populations. The aims of this narrative review are to summarise recent advances in dietary assessment methodologies, with a particular focus on approaches using new technologies, as well as strategies to evaluate tools, and to provide directions for future research.Recent FindingsTechnology as a mode to assess dietary intake has gained momentum in recent years, with the development of image-based methods and wearable devices, as well as the emergence of online methods of administering traditional paper-based approaches to dietary assessment. At the same time, there have been advances in the development of dietary biomarkers to evaluate measures of self-reported dietary intake. Common biomarkers, such as plasma carotenoids and red blood cell fatty acids, are still being utilised with new markers including urinary markers of sugar or wholegrain intake, skin carotenoids as a measure of fruit and vegetable intake. As well, the field of metabolomics shows promise.SummaryChallenges remain in dietary intake assessment, and further efforts are required to refine and evaluate methods so that we can better understand diet-disease relationships and inform guidelines and interventions to promote health.

Measuring practical knowledge about balanced meals: development and validation of the brief PKB-7 scale

Background/Objectives:As a high-quality diet is associated with a lower risk for several diseases and all-cause mortality, current nutrition education tools provide people with information regarding how to build a healthy and a balanced meal. To assess this basic nutrition knowledge, the research aim was to develop and validate a brief scale to measure the Practical Knowledge about Balanced meals (PKB-7).Subjects/Methods:A pool of 25 items was pretested with experts and laypeople before being tested on a random sample in Switzerland (n=517). For item selection, a Rasch model analysis was applied. The validity and reliability of the new scale were assessed by three additional studies including laypeople (n=597; n=145) and nutrition experts (n=59).Results:The final scale consists of seven multiple-choice items, which met the assumptions of the Rasch model. The validity of the new scale was shown by several aspects: the Rasch model was replicated in a second study, and nutrition experts achieved significantly higher scores than laypeople (t(148)=20.27, P<0.001, d=1.78). In addition, the PKB-7 scale was correlated with other nutrition-related constructs and associated with reported vegetable consumption. Test–retest reliability (r=0.68, P<0.001) was acceptable.Conclusions:The PKB-7 scale is a reliable and a valid Rasch-based instrument in Swiss citizens aged between 18 and 80 years for measuring the practical knowledge about balanced meals based on current dietary guidelines. This brief and easy-to-use scale is intended for application in both research and practice.

Position paper on the need for portion-size education and a standardised unit of measurement

Large portion sizes contribute to weight gain in western societies. Portion-size interventions, aids and education can be effective in helping prevent weight gain, but consumers are unsure what appropriate portions are and express confusion about existing guidelines. A lack of clarity about suggested serving size recommendations is a major barrier to food portion-size control. Therefore, standardised measurement units and unambiguous terminologies are required. This position paper summarises the evidence regarding the impact and importance of portion-size education and estimation, and outlines strategies for improving consumer understanding and application of this through the development of an international food measurement system and a range of appropriate portion control tools. In this position paper, the authors call for the standardisation of food volume measurement terminologies, units, implementation recommendations, as well as consumer education. The target audience for this paper includes nutrition and behavioural researchers, policy makers, and stakeholders who potentially influence and implement changes in national food measurement systems, which in turn impact on consumer choice.

Development and Validation of a Brief Instrument to Measure Knowledge About the Energy Content of Meals

Objective: To develop and validate a brief scale to assess knowledge about the energy content of meals for adults in Switzerland. Methods: Based on a random sample, the scale was developed using a Rasch model approach. To assess validity and reliability, the model was replicated and scores were compared with another nutrition knowledge measure and with dietitian trainees’ scores. A test‐retest was performed. Results: Survey studies included 477, 505, and 136 participants from the general population and 59 dietician trainees. The Rasch scale consisted of 11 multiple‐choice items ranging from easy to difficult and correlated with general nutrition knowledge (r = .47; P < .001; r2 = .22). Dietitian trainees achieved higher scores (P < .001; d = 2.17) than did people from the general population; test‐retest reliability results were r = .73, P < .001, and r2 = .53. Conclusions and Implications: Results showed that the scale is efficient, valid, and reliable for use in the general population in Switzerland.

Trends in Food and Beverage Portion Sizes in Australian Children; a Time-Series Analysis Comparing 2007 and 2011–2012 National Data

In 2011–2012 approximately 26% of Australian children aged between 5–17 years were reported to be overweight or obese. Furthermore, the increase in prevalence of overweight and obesity among US children parallels reported increases in energy intake and portion sizes of common foods, leading to the recognition that availability of larger portion sizes contributes to the rise in overweight and obesity prevalence. Thus, the aim of this time-series analysis was to investigate whether selected food portion sizes in Australian children aged 2–16 years changed between 2007 and 2011–2012. Portion size data from 24-h recalls collected in Australian nutrition surveys were compared between 2007 and 2011–2012. Portion sizes changed significantly in 23% of items with increases in 15% and decreases in 8%. Changes in portion sizes varied by age, sex, and food group. Changes occurred for many meat-based items, energy-dense, nutrient-poor food items, breads, cereals, and some fruits and vegetables. Vegetable and fruit portion sizes were below the respective serving sizes of 75 g and 150 g in the Australian Guide to Healthy Eating, while portion sizes of some energy-dense, nutrient-poor foods have increased. These findings suggest approaches to increasing consumption of nutrient-dense core foods and reducing energy-dense, nutrient-poor food items in children are warranted.