A content analysis of online videos containing dietary recommendations for gout and their alignment with evidence-based dietary guidelines.

OBJECTIVE: To assess the alignment of YouTube® videos providing dietary recommendations for gout with evidence-based guidelines targeted at the United Kingdom (UK) population and to establish their quality. DESIGN: A content analysis of YouTube® videos providing dietary recommendations for gout was undertaken. Videos were categorised by video source. Each video's dietary recommendations for gout were compared with three evidence-based guidelines for gout, producing a compliance score. Presence of non-guideline advice was assessed. Understandability and actionability were evaluated using the Patient Education Material Assessment Tool for Audio-Visual Materials. Reliability was assessed using an adapted-DISCERN tool and educational quality using the Global Quality Score Five-Point Scale. Differences between video source and continuous variables were assessed using one-way Kruskal-Wallis H tests. For categorical variables, associations were investigated using Fisher-Freeman-Halton tests. SETTING: Online, May-June 2020. PARTICIPANTS: One-hundred thirty-one videos. RESULTS: Alignment of videos with evidence-based guidelines was poor (median compliance score 27 % (interquartile range 17-37 %)). Additionally, 57 % of videos contained non-guideline advice. The health professional source group had the fewest videos containing non-guideline advice, but this was only significantly lower than the naturopath group (31 % v. 81 %, P = 0·009). Almost 70 % of videos were considered poorly actionable and 50 % poorly understandable. Most videos were rated poor for reliability (79 %) and poor to generally poor for educational quality (49 %). CONCLUSIONS: YouTube® videos providing dietary recommendations for gout frequently fail to conform to evidence-based guidelines, and their educational quality, reliability, understandability and actionability are often poor. More high-quality, comprehensive, evidence-based YouTube® videos are required for UK gout patients.

Comparison of the polyphenol content and in vitro antioxidant capacity of fruit-based nutritional supplements commonly consumed by athletic and recreationally active populations.

Background: Polyphenol-rich fruit supplements are commonly consumed by recreationally active and athletic populations because of their proposed benefits to both exercise performance and recovery from prior exercise. While it has been proposed that 300 mg of polyphenols pre-exercise enhances performance and 1000 mg per day accelerates recovery from muscle damage, it is difficult for consumers to optimize their intake because the polyphenol content of most fruit supplements is not available. Therefore, this study aimed to profile the phenolic and anthocyanin content and in vitro antioxidant capacity of a range of polyphenol-rich fruit supplements on sale in the UK. Methods: Ten polyphenol-rich fruit supplements (six cherry, two pomegranate, one blueberry, and one New Zealand blackcurrant) commonly consumed by athletes were analyzed for total phenols (Folin-Ciocalteu method), total anthocyanins (pH differential method), and in vitro antioxidant capacity (ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC). Results: The ten tested supplements varied markedly per serving in total phenolics (range: 13.8-1007.3 mg/gallic acid equivalents), anthocyanin content (range: 0.19-40.52 mg/cyanidin-3-glucoside), ORAC (range: 150-10,072 µmol of trolox equivalents), and FRAP (range: 72-14,320 µmol of Fe2+ equivalents). Different brands of tart cherry concentrate also exhibited a marked variation in their content of total phenolics (208-591 mg/GAE), anthocyanins (1.5-23.7 mg/cyd-3-glu), and antioxidant capacity (FRAP: 1724-4489 µmol of Fe2+ equivalents; ORAC: 6015-10,072 µmol of TE per serving) per serving. Conclusion: As expected, supplements based on different fruits contained different quantities of anthocyanins and polyphenols. However, there was also a substantial variation within different brands of tart cherry supplements. Because limited compositional information is available on the labels of most fruit-based supplements, the data in this article will enable consumers to select the required volume of the ten tested supplements to meet suggested recommendations for polyphenol intake to enhance performance (300 mg pre-exercise) and accelerate recovery (1000 mg per day) from prior exercise.

Effect of Polyphenol-Rich Foods, Juices, and Concentrates on Recovery from Exercise Induced Muscle Damage: A Systematic Review and Meta-Analysis.

Objectives. To determine the effects of consuming polyphenol-rich foods, juices and concentrates on recovery from exercise-induced muscle damage (EIMD). Method. Eligibility criteria. Randomised and quasi-randomised placebo-controlled trials with a parallel or cross-over design evaluating the effects of consuming polyphenol-rich foods, juices and concentrates on recovery from EIMD in humans. Eligible studies included at least one of the primary outcome measures: maximal isometric voluntary contraction; MIVC, delayed onset muscle soreness; DOMS, or countermovement jump; CMJ. Information sources. AMED, Cochrane Central Register of Controlled Trials, International Clinical Trials Registry Platform, PUBMED, SCOPUS (Elsevier), SPORTDiscus (EBSCO), and the UK Clinical Trials Gateway were searched from inception to September 2020. Risk of bias and quality of evidence. Risk of bias was assessed using Cochrane Risk of Bias 2 tool. Quality of the evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation framework. Synthesis of results. Random effects models were used to determine the effect of polyphenol supplementation on recovery from EIMD. Data are presented as standardised mean differences (SMD) with 95% confidence intervals (CI). Results. Included studies. Twenty-five studies were included; 15 had a parallel, and 10 had a cross-over design. A total of 527 participants (male: n = 425; female: n = 102) were included in the meta-analysis. Synthesis of results. Consumption of polyphenol-rich foods, juices and concentrates accelerated recovery of MIVC immediately post-exercise (SMD = 0.23, 95% CI 0.04, 0.42; p = 0.02; low-quality evidence), 24 h (SMD = 0.39, 95% CI 0.15, 0.62; p = 0.001; low-quality evidence), 48 h (SMD = 0.48, 95% CI 0.28, 0.67; p < 0.001; moderate-quality evidence), 72 h (SMD = 0.29, 95% CI 0.11, 0.46; p = 0.001; low-quality evidence) and 96 h post-exercise (SMD = 0.50, 95% CI 0.16, 0.83; p = 0.004; very low-quality evidence). DOMS was reduced at 24 h (SMD = -0.29, 95% CI -0.47, -0.11; p = 0.002; low-quality evidence), 48 h (SMD = -0.28, 95% CI -0.46, -0.09; p = 0.003; low-quality evidence) and 72 h post-exercise (SMD = -0.46, 95% CI -0.69, -0.24; p < 0.001; very low-quality evidence). CMJ height was greater immediately post-exercise (SMD = 0.27, 95% CI 0.01, 0.53; p = 0.04; low-quality evidence), at 24 h (SMD = 0.47, 95% CI 0.11, 0.83; p = 0.01; very low-quality evidence), 48 h (SMD = 0.58, 95% CI 0.24, 0.91; p < 0.001; very low-quality evidence) and 72 h post-exercise (SMD = 0.57, 95% CI 0.03, 1.10; p = 0.04; very low-quality evidence). Polyphenol supplementation did not alter creatine kinase, c-reactive protein, and interleukin-6 at any time points. At 72 h post-exercise, protein carbonyls (SMD = -0.64, 95% CI -1.14, -0.14; p = 0.01) were reduced. Discussion. Limitations of evidence. Risk of bias was high for 10 studies and moderate for 15. Sensitivity analyses excluding the high risk of bias studies reduced the SMDs for MIVC and DOMS, and for CMJ effects at 24 and 48 h were no longer statistically significant. Interpretation. Consuming polyphenol-rich foods, juices and concentrates accelerated recovery of muscle function while reducing muscle soreness in humans. Maximal benefit occurred 48-72 h post-exercise, however, the certainty of the evidence was moderate to very low. Supplementation could be useful when there is limited time between competitive events and impaired recovery could negatively impact performance.

Effect of tart cherry juice on risk of gout attacks: protocol for a randomised controlled trial.

INTRODUCTION: Gout is a painful form of inflammatory arthritis associated with several comorbidities, particularly cardiovascular disease. Cherries, which are rich in anti-inflammatory and antioxidative bioactive compounds, are proposed to be efficacious in preventing and treating gout, but recommendations to patients are conflicting. Cherry consumption has been demonstrated to lower serum urate levels and inflammation in several small studies. One observational case cross-over study reported that cherry consumption was associated with reduced risk of recurrent gout attacks. This preliminary evidence requires substantiation. The proposed randomised clinical trial aims to test the effect of consumption of tart cherry juice on risk of gout attacks. METHODS AND ANALYSIS: This 12-month, parallel, double-blind, randomised, placebo-controlled trial will recruit 120 individuals (aged 18-80 years) with a clinical diagnosis of gout who have self-reported a gout flare in the previous year. Participants will be randomly assigned to an intervention group, which will receive Montmorency tart cherry juice daily for a 12-month period, or a corresponding placebo group, which will receive a cherry-flavoured placebo drink. The primary study outcome is change in frequency of self-reported gout attacks. Secondary outcome measures include attack intensity, serum urate concentration, fractional excretion of uric acid, biomarkers of inflammation, blood lipids and other markers of cardiovascular risk. Other secondary outcome measures will be changes in physical activity and functional status. Statistical analysis will be conducted on an intention-to-treat basis. ETHICS AND DISSEMINATION: This study has been granted ethical approval by the National Research Ethics Service, Yorkshire and The Humber-Leeds West Research Ethics Committee (ref: 18/SW/0262). Results of the trial will be submitted for publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT03621215.

Vitamin B12 and folate levels in progression of Alzheimer's disease - a short report.

Background: The status of vitamin B12 and folate has been implicated in the development and progression of Alzheimer's disease.Methods: The study explored this issue through a retrospective case-control study design, with follow up of the case group for 18 months. The case group (n = 136) comprised patients 65 years or older diagnosed with Alzheimer's disease and having a Mini-mental State Examination score (MMSE) of ≤ 27. The control group comprised healthy adults 65 years or older (n = 338) with a MMSE score of >27.Results: Vitamin B12 and folate levels were not found to differ between case and control groups. B12 and folate status at baseline was not predictive of disease progression in the case group.Discussion: This lack of association differs from other studies which have shown a protective effect of vitamin B12 and folate on cognitive decline.KEY POINTSThe findings of this study do not confirm evidence suggesting an effect of vitamin B12 and folate levels on development and progression of Alzheimer's disease.Folate and B12 levels were similar in the Alzheimer's group to those of healthy controls.Folate and B12 levels at initial assessment were not predictive of disease progression.

Attitudes and behaviour towards convenience food and food waste in the United Kingdom.

Households in the UK discard much food. A reduction in such waste to mitigate environmental impact is part of UK government policy. This study investigated whether household food waste is linked to a lifestyle reliant on convenience food in younger consumers. A survey of 928 UK residents aged 18-40 years and responsible for the household food shopping (male n = 278; female n = 650) completed an online questionnaire designed to measure attitudes to convenience food and to quantify household food waste. Cluster analysis of 24 food-related lifestyle factors identified 5 consumer groups. General linear modelling techniques were used to test relationships between the purchase frequency of convenience food and household food waste. From the cluster analysis, five distinct convenience profiles emerged comprising: 'epicures' (n = 135), 'traditional consumers' (n = 255), 'casual consumers' (n = 246), 'food detached consumers' (n = 151) and 'kitchen evaders' (n = 141). Casual consumers and kitchen evaders were the most reliant on convenience food and notably were the most wasteful. The demographic profile of kitchen evaders matched the population groups currently targeted by UK food waste policy. Casual consumers represent a new and distinct group characterised by "buy a lot and waste a lot" behaviour. Household size, packaging format, price-awareness and marketing all appear to influence levels of food waste. However, it seems that subtle behavioural and sociocultural factors also have impact. Further research is needed to elucidate the factors that mediate the positive association between the purchase of convenience food and reported food waste in order to inform food waste policy and initiatives.

The influence of academic examinations on energy and nutrient intake in male university students.

BACKGROUND: Taking examinations is central to student experience at University and may cause psychological stress. Although stress is recognised to impact on food intake, the effects of undertaking examinations on students' dietary intake have not been well characterised. The purpose of this study was to assess how students' energy and nutrient intake may alter during examination periods. METHODS: The study design was a within-subject comparison of students' energy and nutrient intake during an examination period contrasted with that outside an examination period (baseline). A total of 20 male students from the University of Sheffield completed an automated photographic 4-d dietary record alongside four 24-h recalls in each time period. Daily energy and nutrient intake was estimated for each student by time period and change in energy and nutrient intake calculated. Intakes at baseline were compared to UK dietary recommendations. Cluster analysis categorised students according to their change in energy intake between baseline and the examination period. Non-parametric statistical tests identified differences by cluster. RESULTS: Baseline intakes did not meet recommendations for energy, non-milk extrinsic sugars, non-starch polysaccharide and sodium. Three defined clusters of students were identified: Cluster D who decreased daily energy intake by 12.06 MJ (n = 5), Cluster S who had similar energy intakes (n = 13) and Cluster I who substantially increased energy intake by 6.37 MJ (n = 2) between baseline and examination period. There were statistically significant differences (all p < 0.05) in change in intake of protein, carbohydrate, calcium and sodium between clusters. Cluster D recorded greater energy, carbohydrate and protein intakes than Cluster I at baseline. CONCLUSIONS: The majority of students were dietary resilient. Students who demonstrated hypophagia in the examination period had a high energy and nutrient intake at baseline, conversely those who showed hyperphagia had a low energy and nutrient intake. These patterns require confirmation in studies including women, but if confirmed, there is need to address some students' poor food choice especially during examinations.

Dietary advice for muscularity, leanness and weight control in Men's Health magazine: a content analysis.

BACKGROUND: The dietary content of advice in men's lifestyle magazines has not been closely scrutinised. METHODS: We carried out an analysis of such content in all 2009 issues (n = 11) of Men's Health (MH) focusing on muscularity, leanness and weight control. RESULTS: Promotion of a mesomorphic body image underpinned advice to affect muscle building and control weight. Diet advice was underpinned by a strong pseudo-scientific discourse, with citation of expert sources widely used to legitimise the information. Frequently multiple dietary components were advocated within one article e.g. fat, omega-3 fatty acids, thiamine, zinc and high-glycaemic index foods. Furthermore advice would cover numerous nutritional effects, e.g. strengthening bones, reducing stress and boosting testosterone, with little contextualisation. The emphasis on attainment of a mesomorphic body image permitted promotion of slimming diets.Advice to increase calorie and protein intake to augment muscle mass was frequent (183 and 262 references, respectively). Such an anabolic diet was advised in various ways, including consumption of traditional protein foods (217 references) and sports foods (107 references), thereby replicating muscle magazines' support for nutritional supplements. Although advice to increase consumption of red meat was common (52 references), fish and non-flesh sources of protein (eggs, nuts & pulses, and soy products) together exceeded red meat in number of recommendations (206 references). Advice widely asserted micronutrients and phytochemicals from plant food (161 references) as being important in muscle building. This emphasis diverges from stereotypical gender-based food consumption patterns.Dietary advice for control of body weight largely replicated that of muscularity, with strong endorsement to consume fruits and vegetables (59 references), diets rich in nuts and pulses and fish (66 references), as well as specific micronutrients and phytochemicals (62 references). Notably there was emphasis on fat-burning, good fats and consumption of single foods, with relatively little mention of dietary restriction. CONCLUSIONS: Despite the widespread use of scientific information to endorse dietary advice, the content, format and scientific basis of dietary content of MH leaves much to be desired. The dietary advice as provided may not be conducive to public health.

Improving the nutritional quality of charitable meals for homeless and vulnerable adults. A case study of food provision by a food aid organisation in the UK.

The prevalence of homelessness in the UK is rising, and demand for food aid through charitable meal services has increased. Charitable services make a substantial contribution to the food and nutrient intake of vulnerable people, and thus offer a platform for dietary improvement. This study examined food provision by a large charitable organisation in a major UK city. It had several objectives: Firstly to quantify nutritional composition of breakfast and lunch meals, secondly to understand factors that influence the composition of menus and meals, and thirdly to determine whether, within the context of these influences, improvements to the menu would be possible and whether these would be acceptable to clients. Mixed methods of ethnography, semi-structured interviews, quantitative nutrient analysis, recipe adaptation and taste tests were employed. The research team worked as volunteers in the organisation for a 3-week period and interviews were held with the kitchen staff. Food choice was recorded for 189 clients at breakfast and 251 clients at lunch over a 5-day period and nutrient content of these meals was estimated. Meals were weighted towards fat and sugar energy. Energy, potassium, calcium, vitamin C, vitamin A, zinc and magnesium content of meals were below Dietary Reference Value (DRV) targets for at least 20% of breakfast and lunch meals. Such inadequacies may be addressed by the addition of simple foods to the breakfast menu and adaptation of lunchtime recipes. Twelve lunchtime dishes were proposed and eight of these were seemingly acceptable to clients in taste testing. Barriers to provision of healthier meals include budget, food donations and acceptability of meals.

Effect of a tart cherry juice supplement on arterial stiffness and inflammation in healthy adults: a randomised controlled trial.

Tart cherries are a particularly rich source of anthocyanins. Evidence indicates that dietary intake of anthocyanins is inversely associated with arterial stiffness. We conducted an open-label randomised placebo controlled study to determine whether a tart cherry juice concentrate (Cherry Active) reduced arterial stiffness, inflammation and risk markers for cardiovascular disease in 47 healthy adults (30-50 years). Participants consumed 30 ml of cherry concentrate diluted to a volume of 250 ml with water or the same volume of an energy matched control drink daily for six weeks. Measurements were taken at baseline and at the end of the intervention. There was no effect of the intervention on arterial stiffness (P = 0.218), c-reactive protein (P = 0.220), systolic blood pressure (P = 0.163), diastolic blood pressure (P = 0.121), total cholesterol (P = 0.342) and high density lipoprotein cholesterol (P = 0.127). At the end of the intervention, plasma antioxidant capacity (measured as the ferric reducing ability of plasma (FRAP)) was significantly higher in the intervention group than the control group (P = 0.012). We conclude that a tart cherry juice concentrate rich in anthocyanins has no effect on arterial stiffness, c-reactive protein and risk markers for cardiovascular disease, but evokes a minor increase in antioxidant status in healthy adults.

Long-chain polyunsaturated fatty acid supplementation had no effect on body weight but reduced energy intake in overweight and obese women.

Longer-chain polyunsaturated fatty acids may have greater appetite-suppressing effects than shorter-chain, monosaturated, and saturated fatty acids. Because fish oils are predominantly composed of n-3 long-chain polyunsaturated fatty acid and may assist in the treatment of obesity comorbidities, their effect on body weight and body mass index is of interest. We hypothesized that daily supplementation with docosahexaenoic acid (DHA)-rich oil would reduce energy intake and body weight in overweight and obese women compared with supplementation with oleic acid (OA) rich oil. A double-blinded, randomized, parallel intervention was conducted. Body mass index (in kilograms per meter squared), body weight (in kilograms), body fat (in percent), and lean tissue (in kilograms) were measured at baseline and 12 weeks after intervention with DHA or OA. Diet diaries were also completed at these time points for estimation of energy and macronutrient intake. Subjects reported significantly lower energy (P = .020), carbohydrate (g) (P = .037), and fat (g) (P = .045) intake after DHA compared with OA. Body mass or composition was not affected by treatment, although a fall in body weight in the DHA group approached statistical significance (P = .089). Daily ingestion of DHA over a 12-week period may reduce energy intake in overweight and obese females, but longer-term and adequately powered studies using subjects of both sexes are needed. Other factors that should be considered include the following: the choice of control, the body mass index category of subjects, and ways of improving the compliancy and accuracy of dietary assessment.

Temporality in British young women's magazines: food, cooking and weight loss.

OBJECTIVE: The present study examines seasonal and temporal patterns in food-related content of two UK magazines for young women focusing on food types, cooking and weight loss. DESIGN: Content analysis of magazines from three time blocks between 1999 and 2011. SETTING: Desk-based study. SUBJECTS: Ninety-seven magazines yielding 590 advertisements and 148 articles. RESULTS: Cluster analysis of type of food advertising produced three clusters of magazines, which reflected recognised food behaviours of young women: vegetarianism, convenience eating and weight control. The first cluster of magazines was associated with Christmas and Millennium time periods, with advertising of alcohol, coffee, cheese, vegetarian meat substitutes and weight-loss pills. Recipes were prominent in article content and tended to be for cakes/desserts, luxury meals and party food. The second cluster was associated with summer months and 2010 issues. There was little advertising for conventional foods in cluster 2, but strong representation of diet plans and foods for weight loss. Weight-loss messages in articles focused on short-term aesthetic goals, emphasising speedy weight loss without giving up nice foods or exercising. Cluster 3 magazines were associated with post-New Year and 2005 periods. Food advertising was for everyday foods and convenience products, with fewer weight-loss products than other clusters; conversely, article content had a greater prevalence of weight-loss messages. CONCLUSIONS: The cyclical nature of magazine content - indulgence and excess encouraged at Christmas, restraint recommended post-New Year and severe dieting advocated in the summer months - endorses yo-yo dieting behaviour and may not be conducive to public health.

Meeting school food standards - students' food choice and free school meals.

OBJECTIVE: To examine students' school food choice in relation to school food standards and entitlement to free school meals (FSM). DESIGN: Cross-sectional analysis of students' school food choices. SETTING: Two large secondary schools in Yorkshire, England. SUBJECTS: Students (n 2660) aged 11­18 years. RESULTS: Sandwiches and pizza were the most popular main food items: 40·4 % and 31·2 %, respectively, in School A; 48·3 % and 27·3 %, respectively, in School B. More nutritionally valuable 'dishes of the day' accounted for 8·7 % and 8·3 % of main foods for School A and School B, respectively. FSM students were more likely (P < 0·0 0 1) to choose main foods (School A: FSM 87·04 %, non-FSM 70·28 %; School B: FSM 75·43 %, non-FSM 56·13 %). Dishes of the day were chosen on a significantly greater (P < 0·0 0 1) percentage of days by FSM v. non-FSM students (School A: FSM 15·67 %, non-FSM 7·11 %; School B: FSM 19·42 %, non-FSM 5·17 %). CONCLUSIONS: Despite the availability of nutritionally valuable dishes of the day, the most popular food items were sandwiches, pizza and desserts. FSM students were more likely to choose the more nutritionally valuable dish of the day. School food standards should be reassessed in light of students' preferences.

Water intake and post-exercise cognitive performance: an observational study of long-distance walkers and runners.

PURPOSE: The impact of diet on endurance performance and cognitive function has been extensively researched in controlled settings, but there are limited observational data in field situations. This study examines relationships between nutrient intake and cognitive function following endurance exercise amongst a group of 33 recreational runners and walkers. METHODS: All participants (mean age of 43.2 years) took part in a long-distance walking event and completed diet diaries to estimate nutrient intake across three-time periods (previous day, breakfast and during the event). Anthropometric measurements were recorded. Cognitive tests, covering word recall, ruler drop and trail making tests (TMT) A and B were conducted pre- and post-exercise. Participants rated their exercise level on a validated scale. Nutrient intake data were summarised using principal components analysis to identify a nutrient intake pattern loaded towards water intake across all time periods. Regression analysis was used to ascertain relationships between water intake component scores and post-exercise cognitive function, controlling for anthropometric measures and exercise metrics (distance, duration and pace). RESULTS: Participants rated their exercise as 'hard-heavy' (score 14.4, ±3.2). Scores on the water intake factor were associated with significantly faster TMT A (p = 0.001) and TMT B (p = 0.005) completion times, and a tendency for improved short-term memory (p = 0.090). Water intake scores were not associated with simple reaction time (assessed via the ruler drop test). CONCLUSION: These data are congruent with experimental research demonstrating a benefit of hydration on cognitive function. Further field research to confirm this relationship, supported with precise measures of body weight, is needed.

A vitamin B-12 supplement of 500 µg/d for eight weeks does not normalize urinary methylmalonic acid or other biomarkers of vitamin B-12 status in elderly people with moderately poor vitamin B-12 status.

Plasma vitamin B-12 is the most commonly used biomarker of vitamin B-12 status, but the predictive value for low vitamin B-12 status is poor. The urinary methylmalonic acid (uMMA) concentration has potential as a functional biomarker of vitamin B-12 status, but the response to supplemental vitamin B-12 is uncertain. A study was conducted to investigate the responsiveness of uMMA to supplemental vitamin B-12 in comparison with other biomarkers of vitamin B-12 status [plasma vitamin B-12, serum holotranscobalamin (holoTC), plasma MMA] in elderly people with moderately poor vitamin B-12 status. A double-blind, placebo-controlled, randomized 8-wk intervention study was carried out using vitamin B-12 supplements (500 µg/d, 100 µg/d, and 10 µg/d cyanocobalamin) in 100 elderly people with a combined plasma vitamin B-12 <250 pmol/L and uMMA ratio (µmol MMA/mmol creatinine) >1.5. All biomarkers had a dose response to supplemental vitamin B-12. Improvements in plasma vitamin B-12 and serum holoTC were achieved at cobalamin supplements of 10 µg/d, but even 500 µg/d for 8 wk did not normalize plasma vitamin B-12 in 8% and serum holoTC in 12% of people. The response in uMMA was comparable with plasma MMA; 15-25% of people still showed evidence of metabolic deficiency after 500 µg/d cobalamin for 8 wk. There was a differential response in urinary and plasma MMA according to smoking behavior; the response was enhanced in ex-smokers compared with never-smokers. uMMA offers an alternative marker of metabolic vitamin-B12 status, obviating the need for blood sampling.

Effects of pomegranate juice supplementation on pulse wave velocity and blood pressure in healthy young and middle-aged men and women.

Pomegranate juice may improve cardiovascular risk because of its content of antioxidant polyphenols. We conducted a randomized placebo-controlled parallel study to examine the effect of pomegranate juice on pulse wave velocity (PWV), blood pressure (BP) and plasma antioxidant status (ferric reducing power; FRAP) in 51 healthy adults (30-50 years). Participants consumed 330 ml/day of pomegranate juice or control drink for four weeks. Measurements were made at baseline and at four weeks. There was no effect of the intervention on PWV (P = 0.694) and plasma FRAP (P = 0.700). However, there was a significant fall in systolic blood pressure (-3.14 mmHg, P < 0.001), diastolic blood pressure (-2.33 mmHg P < 0.001) and mean arterial pressure (-2.60 mmHg, P < 0.001). Change in weight was similar in the two groups over the intervention period (P = 0.379). The fall in BP was not paralleled by changes in concentration of serum angiotensin converting enzyme. We conclude that pomegranate juice supplementation has benefits for BP in the short term, but has no effect on PWV. The mechanism for the effect is uncertain.

Determinants of urinary methylmalonic acid concentration in an elderly population in the United Kingdom.

BACKGROUND: An age-related deterioration of vitamin B-12 status has been well documented. The early detection of deficiency may prevent the development of serious clinical symptoms, but plasma vitamin B-12 concentration is known to be an imperfect measure of vitamin B-12 status. Urinary methylmalonic acid (MMA) may be a more informative biomarker of vitamin B-12 status; however, biochemical, dietary, and other lifestyle determinants are not known. OBJECTIVE: We identified determinants of urinary MMA concentrations in free-living men and women aged ≥65 y in the United Kingdom. DESIGN: A cross-sectional study in 591 men and women aged 65-85 y, with no clinical evidence of vitamin B-12 deficiency, was conducted to determine the demographic, clinical, and lifestyle determinants of urinary MMA concentration expressed as the ratio of micromoles of MMA to millimoles of creatinine (uMMA ratio). RESULTS: Twenty percent of subjects had plasma vitamin B-12 concentrations <200 pmol/L. Seventeen percent of the variation in the uMMA ratio could be explained by plasma holotranscobalamin and sex; total vitamin B-12 intake and measures of renal function and gastric function made only a small contribution to the model. The uMMA ratio was lower in people with moderately impaired renal function. CONCLUSIONS: Plasma holotranscobalamin and sex were the most important determinants of uMMA ratio in elderly people with no clinical diagnosis of renal impairment. This biomarker might underestimate vitamin B-12 deficiency in a population in which renal impairment is prevalent. This trial was registered at www.controlled-trials.com as ISRCJN83921062.

Effect of different long-chain fatty acids on cholecystokinin release in vitro and energy intake in free-living healthy males.

Long-chain fatty acids have been shown to suppress appetite and reduce energy intake (EI) by stimulating the release of gastrointestinal hormones such as cholecystokinin (CCK). The effect of NEFA acyl chain length on these parameters is not comprehensively understood. An in vitro screen tested the capacity of individual NEFA (C12 to C22) to trigger CCK release. There was a gradient in CCK release with increasing chain length. DHA (C22) stimulated significantly (P < 0.01) more CCK release than all other NEFA tested. Subsequently, we conducted a randomised, controlled, crossover intervention study using healthy males (n 18). The effects of no treatment (NT) and oral doses of emulsified DHA-rich (DHA) and oleic acid (OA)-rich oils were compared using 24 h EI as the primary endpoint. Participants reported significantly (P = 0.039) lower total daily EI (29 % reduction) with DHA compared to NT. There were no differences between DHA compared to OA and OA compared to NT. There was no between-treatment difference in the time to, or EI of, the first post-intervention eating occasion. It is concluded that NEFA stimulate CCK release in a chain length-dependent manner up to C22. These effects may be extended to the in vivo setting, as a DHA-based emulsion significantly reduced short-term EI.

Evaluation of the salivary proteome as a surrogate tissue for systems biology approaches to understanding appetite.

Current measurement of appetite depends upon tools that are either subjective (visual analogue scales), or invasive (blood). Saliva is increasingly recognised as a valuable resource for biomarker analysis. Proteomics workflows may provide alternative means for the assessment of appetitive response. The study aimed to assess the potential value of the salivary proteome to detect novel biomarkers of appetite using an iTRAQ-based workflow. Diurnal variation of salivary protein concentrations was assessed. A randomised, controlled, crossover study examined the effects on the salivary proteome of isocaloric doses of various long chain fatty acid (LCFA) oil emulsions compared to no treatment (NT). Fasted males provided saliva samples before and following NT or dosing with LCFA emulsions. The oil component of the DHA emulsion contained predominantly docosahexaenoic acid and the oil component of OA contained predominantly oleic acid. Several proteins were present in significantly (p<0.05) different quantities in saliva samples taken following treatments compared to fasting samples. DHA caused alterations in thioredoxin and serpin B4 relative to OA and NT. A further study evaluated energy intake (EI) in response to LCFA in conjunction with subjective appetite scoring. DHA was associated with significantly lower EI relative to NT and OA (p=0.039). The collective data suggest investigation of salivary proteome may be of value in appetitive response. This article is part of a Special Issue entitled: Proteomics: The clinical link.

Calcium supplementation and bone mineral accretion in adolescent girls: an 18-mo randomized controlled trial with 2-y follow-up.

BACKGROUND: A recent meta-analysis raised doubt as to whether calcium supplementation in children benefits spine and hip bone mineral density (BMD). OBJECTIVE: We used state-of-the-art measures of bone (fan-beam dual-energy X-ray absorptiometry and 4 bone turnover markers) to determine whether girls with low habitual calcium intake benefited from supplementation with a soluble form of calcium (calcium citrate malate dissolved in a fruit drink). DESIGN: The trial was an 18-mo randomized trial of calcium supplementation (792 mg/d) with follow-up 2 y after supplement withdrawal. Subjects were 96 girls (mean age: 12 y) with low calcium intakes (mean: 636 mg/d). The main outcome measure was change in total-body, lumbar spine, and total hip bone mineral content (BMC) during supplementation and 2 y after supplement withdrawal. Changes in BMD and bone turnover markers were secondary outcome measures. RESULTS: The mean additional calcium intake in the supplemented group was 555 mg/d. Compared with the control group, the supplemented group showed significantly (P < 0.05) greater gains in BMC (except at the total hip site) over the 18-mo study. BMD change was significantly (P < 0.05) greater for all skeletal sites, and concentrations of bone resorption markers and parathyroid hormone were significantly (P < 0.01) lower in the supplemented group than in the control group after 18 mo. After 42 mo, gains in BMC and BMD and differences in bone resorption were no longer evident. CONCLUSIONS: Calcium supplementation enhances bone mineral accrual in teenage girls, but the effect is short-lived. The likely mechanism for the effect of the calcium is suppression of bone turnover, which is reversed upon supplement withdrawal.