New sources of polyunsaturated fatty acids

Two groups of essential fatty acids (n-6 and n-3) are needed in a healthy human diet. Current advice suggests an optimal ratio of about 4:1 for these polyunsaturated fatty acids (PUFAs) in the diet but in Western countries it is usually 10-20:1. The n-3 PUFAs are synthesized in photosynthetic organisms from where they move up the food chain. Fish in particular, are a rich source of twenty and twenty two carbon n-3 PUFAs which are particularly effective for humans. Fish oils have been shown to be beneficial in a variety of chronic inflammatory diseases. However, fish stocks arc under threat. Therefore, fish farming has increased recently and offers some opportunities for viable sources of n-3 PUFAs, especially since disposal of fish farm waste is expensive and environmentally problematic. In this project, we investigated trout ( Oncorhynchus mykiss) as a potential source of n-3 PUFAs. The lipid composition of different tissues was analysed by combinations of TLC and GLC. This work identified the differences between various individual tissues and pin-pointed those with high eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) content. Two possible industrial lipid extraction methods were compared with a standard laboratory procedure. These studies included a comparison of yields for offal which had been stored for various times. The rendering method, although not as efficient as the laboratory procedure (Garbus), was concluded to allow oil yield for nutraceutical development although tissues could not be stored for greater than two days without compromised quality. Finally, oil extracts from trout (containing 2.5% EPA and 10.5% DHA) were tested in a model system (bovine cartilage explants) as treatment for osteoarthritis. The trout oil preparation significantly reduced cytokine-induced glycosaminoglycan release indicating a protective action. However, it was not as effective as pure EPA or DHA. Moreover, the trout oil preparation was not able to reduce mRNA levels of inflammatory genes (e.g., COX-2, IL-6, ADAMTS-4, -5 and MMP-3) which were lowered by pure EPA or DHA supplementation. We conclude that trout waste is a viable source of n-3 PUFAs for nutraceutical development but that processing will probably be needed to produce a dietary supplement with potent anti inflammatory properties

Global cities and cultural diversity: challenges and opportunities for young people’s nutrition.

Childhood obesity is a common concern across global cities and threatens sustainable urban development. Initiatives to improve nutrition and encourage physical exercise are promising but are yet to exert significant influence on prevention. Childhood obesity in London is associated with distinct ethnic and socio-economic patterns. Ethnic inequalities in health-related behaviour endure, underpinned by inequalities in employment, housing, access to welfare services, and discrimination. Addressing these growing concerns requires a clearer understanding of the socio-cultural, environmental and economic contexts of urban living that promote obesity. We explore opportunities for prevention using asset based-approaches to nutritional health and well-being, with a particular focus on adolescents from diverse ethnic backgrounds living in London. We focus on the important role that community engagement and multi-sectoral partnership play in improving the nutritional outcomes of London's children. London's children and adolescents grow up in the rich cultural mix of a global city where local streets are characterised by diversity in ethnicities, languages, religions, foods, and customs, creating complex and fluid identities. Growing up with such everyday diversity we argue can enhance the quality of life for London's children and strengthen their social capital. The Determinants of young Adult Social well-being and Health longitudinal study of about 6500 of London's young people demonstrated the positive impact of cultural diversity. Born to parents from over a hundred countries and exposed to multi-lingual households and religious practices, they demonstrated strong psychological resilience and sense of pride from cultural straddling, despite material disadvantage and discrimination. Supporting the potential contribution of such socio-cultural assets is in keeping with the values of social justice and equitable and sustainable development. Our work signals the importance of community engagement and multisectoral partnerships, involving, for example, schools and faith-based organisations, to improve the nutrition of London's children

Adiposity and cardiovascular outcomes in three-year-old children of participants in UPBEAT, an RCT of a complex intervention in pregnant women with obesity

Background: Maternal obesity is associated with offspring cardiometabolic risk. UPBEAT was a randomised controlled trial of an antenatal diet and physical activity intervention in 1555 women with obesity. The intervention was associated with lower gestational weight gain, healthier diet and metabolic profile in pregnancy, and reduced infant adiposity at six months. Objective: We have investigated whether the UPBEAT intervention influenced childhood cardiometabolic outcomes or was associated with sustained improvements in maternal lifestyle 3-years after delivery. Methods: In UPBEAT mother-child dyads at the 3-year follow-up, we assessed childhood blood pressure, resting pulse rate, and adiposity (body mass index, skinfold thicknesses, body fat, waist and arm circumferences) and maternal diet, physical activity, and anthropometry. Results: 514 three-year-old children attended the appointment (49% intervention, 51% standard care). There was no difference in the main outcome of interest, subscapular skinfold thickness, between the trial arms (−0.30 mm, 95% confidence interval: −0.92, 0.31). However, the intervention was associated with a lower resting pulse rate (−5 bpm [−8.41, −1.07]). There was also a non-significant lower odds of overweight/obesity (OR 0.73; 0.50, 1.08). Maternal dietary improvements observed in the UPBEAT trial, including glycaemic load and saturated fat were maintained 3-years postpartum. Conclusion: This study has demonstrated that an antenatal dietary and physical activity intervention in women with obesity is associated with lower offspring pulse rate and sustained improvement in maternal diet. Whilst larger than previous cohorts, there remains potential for bias from attrition and these findings require validation in future cohorts

Protein status of people with phenylketonuria: A scoping review protocol

INTRODUCTION: Phenylketonuria (PKU) is a disorder of protein metabolism resulting in an accumulation of phenylalanine in the body. Dietary management consists of altering the sources of ingested protein to limit phenylalanine intake. Current dietary protein guidelines for PKU are based on limited scientific evidence, thus it remains unclear whether current practice leads to optimal protein status in people with PKU. To date, no attempt has been made to systematically evaluate the protein status of people with PKU, using a combination of validated anthropometric, biochemical and functional measurement tools. Furthermore, factors known to influence protein status in the general population warrant consideration when determining protein status in individuals with PKU, alongside factors unique to PKU such as the type of protein substitute consumed. Understanding the impact of these variables on protein status is crucial to developing a personalised approach to protein recommendations for optimising health and functional outcomes in people with PKU. Therefore, the aim of this scoping review is to examine existing evidence regarding the protein status of people with PKU, and to investigate the nutritional and lifestyle variables that influence protein status. METHODS AND ANALYSIS: This review will be guided by Arksey and O’Malley’s framework, along with guidance from Levac et al, Pawliuk et al and the Joanna Briggs Institute. The following databases will be searched: MEDLINE (Ovid), Embase, CENTRAL, Web of Science and Scopus, alongside grey literature. Identified literature will be assessed by two independent reviewers for inclusion. Descriptive numerical analysis will be performed and a narrative summary will accompany the tabulated results describing how study findings relate to the review questions. ETHICS AND DISSEMINATION: This review protocol does not require ethical approval. Findings will be disseminated through peer-reviewed publication, presented at relevant conferences, and shared with a patient research advisory group to inform discussions on future research

Short sleep duration, glucose dysregulation and hormonal regulation of appetite in men and women

STUDY OBJECTIVE: To determine the hormonal effects of reducing sleep duration under controlled feeding conditions. DESIGN: Randomized, crossover study. SETTING: Inpatient. PARTICIPANTS: Twenty-seven normal weight, 30- to 45-yr-old men and women habitually sleeping 7-9 hr/night. INTERVENTION: Participants were studied under two sleep conditions: short (4 hr in bed) or habitual (9 hr in bed) sleep. A controlled diet was provided for each 4-day study period. MEASUREMENTS AND RESULTS: Fasting blood samples were obtained daily and frequent blood samples were obtained throughout day 4. The main outcomes measures included glucose, insulin, leptin, ghrelin, adiponectin, total glucagon-like peptide 1 (GLP-1) and peptide YY(3-36) (PYY(3-36)) concentrations. Body weights were reduced by 2.2 ± 0.4 lb and 1.7 ± 0.4 lb during the habitual and short sleep phases, respectively (both P < 0.0001). There was no effect of sleep duration on glucose, insulin, and leptin profiles (all P > 0.05). Ghrelin and GLP-1 responses differed by sex. Short sleep increased fasting (P = 0.054) and morning (08:00-12:00) (P = 0.042) total ghrelin in men but not women. The reverse was observed for GLP-1: afternoon levels (12:30-19:00) were lower (P = 0.016) after short sleep compared with habitual sleep in women but not men. CONCLUSIONS: These data suggest that, in the context of negative energy balance, short sleep does not lead to a state of increased insulin resistance, but may predispose to overeating via separate mechanisms in men and women. CLINICAL TRIAL INFORMATION: Trial registration on http://www.clinicaltrials.gov. #NCT00935402. CITATION: St-Onge MP; O'Keeffe M; Roberts AL; RoyChoudhury A; Laferrère B. Short sleep duration, glucose dysregulation and hormonal regulation of appetite in men and women. SLEEP 2012;35(11):1503-1510