Hertfordshire, United Kingdom
Hertfordshire, United Kingdom

Time filter

Source Type

Wallace A.M.,Royal Infirmary | Gibson S.,Ashwell Associates Europe Ltd | de la Hunty A.,Ashwell Associates Europe Ltd | Lamberg-Allardt C.,University of Helsinki | Ashwell M.,Ashwell Associates Europe Ltd
Steroids | Year: 2010

In this review we describe procedures, performance characteristics and limitations of methods available for the measurement of 25-hydroxyvitamin (25OHD) since the year 2000. The two main types of methods are competitive immunoassay and those based on chromatographic separation followed by non-immunological direct detection (HPLC, LC-MS/MS). Lack of a reference standard for 25OHD has, until recently, been a major issue resulting in poor between-method comparability. Fortunately this should soon improve due to the recent introduction of a standard reference material in human serum (SRM 972) from the National Institute of Standards and Technology (NIST). For immunoassay, specificity can be an issue especially in relation to the proportion of 25OHD2 that is quantified whereas HPLC and LC-MS/MS methods are able to measure the two major vitamin D metabolites 25OHD2 and 25OHD3 independently. HPLC and LC-MS/MS require more expensive equipment and expert staff but this can be offset against lower reagent costs. Increasingly procedures are being developed to semi-automate or automate HPLC and LC-MS/MS but run times remain considerably longer than for immunoassays especially if performed on automated platforms. For most HPLC and LC-MS/MS methods extraction and procedural losses are corrected for by the inclusion of an internal standard which, in part, may account for higher results compared to immunoassay. In general precision of immunoassay, HPLC and LC-MS/MS are comparable and all have the required sensitivity to identify severe vitamin D deficiency. Looking to the future it is hoped that the imminent introduction of a standard reference method (or methods) for 25OHD will further accelerate improvements in between method comparability. © 2010 Elsevier Inc. All rights reserved.


Cavelaars A.E.J.M.,Wageningen University | Doets E.L.,Wageningen University | Dhonukshe-Rutten R.A.M.,Wageningen University | Hermoso M.,Ludwig Maximilians University of Munich | And 9 more authors.
European Journal of Clinical Nutrition | Year: 2010

Background: The EURRECA (EURopean micronutrient RECommendations Aligned) Network of Excellence (http: //www.eurreca.org) is working towards the development of aligned recommendations. A protocol was required to assign resources to those micronutrients for which recommendations are most in need of alignment.Methods: Three important a priori criteria were the basis for ranking micronutrients: (A) the amount of new scientific evidence, particularly from randomized controlled trials; (B) the public health relevance of micronutrients; (C) variations in current micronutrient recommendations. A total of 28 micronutrients were included in the protocol, which was initially undertaken centrally by one person for each of the different population groups defined in EURRECA: infants, children and adolescents, adults, elderly, pregnant and lactating women, and low income and immigrant populations. The results were then reviewed and refined by EURRECA's population group experts. The rankings of the different population groups were combined to give an overall average ranking of micronutrients.Results: The 10 highest ranked micronutrients were vitamin D, iron, folate, vitamin B12, zinc, calcium, vitamin C, selenium, iodine and copper. Conclusions: Micronutrient recommendations should be regularly updated to reflect new scientific nutrition and public health evidence. The strategy of priority setting described in this paper will be a helpful procedure for policy makers and scientific advisory bodies. © 2010 Macmillan Publishers Limited All rights reserved.


Koletzko B.,Ludwig Maximilians University of Munich | Szajewska H.,Medical University of Warsaw | Ashwell M.,Ashwell Associates Europe Ltd. | Shamir R.,Tel Aviv University | And 19 more authors.
Annals of Nutrition and Metabolism | Year: 2012

The Early Nutrition Academy and the Child Health Foundation, in collaboration with the Committee on Nutrition, European Society for Paediatric Gastroenterology, Hepatology and Nutrition, held a workshop in March 2011 to explore guidance on acquiring evidence on the effects of nutritional interventions in infants and young children. The four objectives were to (1) provide guidance on the quality and quantity of evidence needed to justify conclusions on functional and clinical effects of nutrition in infants and young children aged <3 years; (2) agree on a range of outcome measures relevant to nutrition trials in this age group for which agreed criteria are needed; (3) agree on an updated 'core data set' that should generally be recorded in nutrition trials in infants and young children, and (4) provide guidance on the use of surrogate markers in paediatric nutrition research. The participants discussed these objectives and agreed to set up six first working groups under the auspices of the Consensus Group on Outcome Measures Made in Paediatric Enteral Nutrition Clinical Trials (COMMENT). Five groups will aim to identify and define criteria for assessing key outcomes, i.e. growth, acute diarrhoea, atopic dermatitis and cows' milk protein allergy, infections and 'gut comfort'. The sixth group will review and update the 'core data set'. The COMMENT Steering Committee will discuss and decide upon a method for reaching consensus which will be used by all working groups and plan to meet again within 2 years and to report and publish their conclusions. Copyright © 2012 S. Karger AG, Basel.


Ashwell M.,Ashwell Associates Europe Ltd | Ashwell M.,Oxford Brookes University
Open Obesity Journal | Year: 2011

This review focuses on the rationale behind the charts that have been used as public health tools to assess the health risks of obesity, with special emphasis on where the boundary values are placed. A chart based on body mass index (BMI) was introduced in the 1980s to replace Tables of best weights for heights and this BMI chart (based on adult weight for height) is still very much in use today. Although the importance of the distribution of body fat, as opposed to the total amount of body fat, in determining health risks of obesity was first suggested in the 1940s, it was not until the mid 1990s that a chart based on Shape was suggested. The Ashwell ® Shape Chart was based on the use of waist-to-height ratio (WHtR) as a proxy for abdominal obesity. The chart contains three boundary values for WHtR: 0.4, 0.5 and 0.6; originally set on pragmatic decisions. Substantial evidence from a recent systematic review now supports the global boundary value WHtR of 0.5 for Consider Action. WHtR of 0.6 has been proposed for Take Action. An exciting prospect is that the same Shape Chart might be used to assess risk for adults and children in several ethnic groups. Use of the Shape Chart could also improve the efficiency for screening for cardiometabolic risk and could provide substantial cost savings in terms of obesity treatment. The public health message could not be simpler: Keep your waist circumference to less than half your height. © Margaret Ashwell.


Ashwell M.,Ashwell Associates Europe Ltd | Ashwell M.,Oxford Brookes University | Browning L.M.,Ashwell Associates Europe Ltd
Open Obesity Journal | Year: 2011

We have recently performed a systematic review which collated seventy eight cross-sectional and prospective studies exploring waist-to-height ratio and waist circumference or body mass index as predictors of diabetes and cardiovascular disease published in English between 1950 and 2008. This review, which also employed specificity and sensitivity comparisons, indicated that waist-to-height ratio could be a useful global clinical screening tool, with a weighted mean boundary value of 0.5, supporting the simple public health message "keep your waist circumference to less than half your height". During the collation of evidence, we noticed inconsistency in the site of measurement of waist circumference and also the terminology and abbreviations used to describe 'waist-to-height ratio'. We encourage others to routinely use the waist circumference measurement used most often (that recommended by World Health Organization - mid way between the lower rib and the iliac crest) and the terminology 'waist-to-height ratio' abbreviated to WHtR to avoid confusion about this anthropometric index which is growing in popularity for screening for cardiometabolic risk. © Ashwell and Browning.


Lambert J.P.,Lambert Nutrition Consultancy Ltd | Ashwell M.,Ashwell Associates Europe Ltd
European Journal of Clinical Nutrition | Year: 2010

Objectives: The EURRECA Network of Excellence is developing standardized methods that will guide the alignment of micronutrient reference values (RVs) across Europe. A consultation process to identify and prioritize the best practice, tools or guidance for EURRECA was undertaken. Subjects/Methods: A questionnaire was sent to 90 individuals with experience of setting or using RVs. Respondents were asked to rank the usefulness of each type of possible guidance. Results: In all, 52% of individuals returned completed questionnaires. For the planning process, the most needed guidance was on the best way to assess the status quo of RVs; what to cover, setting priorities, how to take into consideration the diverse needs of the users; and making the whole process transparent. The most needed guidance for the active stage of development was how to obtain valid and robust data on intakes and status to use as a base for RVs; how to account for food-related factors; how to incorporate results of systematic reviews; how to identify unbiased and independent reviews and make decisions if evidence is conflicting; methods to weight the evidence; and formats or concepts to convert scientific requirements into RVs. Users of RVs required guidance on communication, codes of practice to raise professional and public awareness, making them easy to use in the intended way. Conclusions: The questionnaire responses provided views from a wide range of experts on the most needed tools and standardized methodologies for the process of reviewing micronutrient RVs. This will help the EURRECA Network of Excellence to prioritize resources. © 2010 Macmillan Publishers Limited All rights reserved.


Gibson S.,SIG | Ashwell M.,Ashwell Associates Europe Ltd
Public Health Nutrition | Year: 2011

Objective To examine dietary patterns among British adults, associations with Na and macronutrient intakes, and implications for dietary advice.Design Principal component analysis of 7 d weighed dietary records.Subjects Adults aged 19-64 years (n 1724).Setting National Diet and Nutrition Survey (2000/2001).Results High Na intake was associated with more energy-dense diets, higher in fat and SFA (percentage of energy) but lower in non-milk extrinsic sugars (NMES). Eight patterns (PC1 to PC8) explained 40 % of the total variance in food intakes. Three patterns - PC3 (high loadings on bread, fats and cheese), PC2 (meat products, eggs and chips) and PC7 (red meat, sauces and alcohol) - were associated with high Na intake. Of these, PC3 correlated with high Na density and Na:K ratio, while PC2 correlated with fat. By contrast, three patterns - 'health-conscious' (PC1; vegetables, fruit, fruit juice, fish), 'breakfast cereals and milk' (PC6) and 'chicken and rice' (PC8) - were associated with modest Na intake, lower Na density and lower fat and SFA. PC2 was positively correlated, and PC1 was negatively correlated, with adding salt to food. Other patterns were 'tea/coffee and cakes' (PC4; associated with high SFA and NMES) and 'soft drinks and snacks' (PC5; associated with high NMES but not fat or SFA). The dietary patterns of males and females differed slightly.Conclusions Dietary patterns PC1, PC6, PC8 (vegetables, fruit, fish, milk, breakfast cereals, poultry) were broadly compatible with guidelines for salt, fat, SFA and NMES. However, other patterns tended to be high in either salt or NMES. © 2011 The Authors.

Loading Ashwell Associates Europe Ltd collaborators
Loading Ashwell Associates Europe Ltd collaborators