Relationships between threshold-based PROP sensitivity and food preferences of Tunisians

International audienceThe extent to which taste responses - and notably the genetically determined sensitivity to 6-npropylthiouracil (PROP) - influences food preferences and food use is still a matter of debate. We addressed the issue on the basis of a behavioural and anthropological study performed in Tunis in 1999. The working sample consists of 123 adults of both sexes (38 men, 85 women), aged 19 to 59, in various social categories. Taste recognition thresholds for sucrose, fructose, sodium chloride, quinine hydrochloride, citric acid, tannic acid, oak tannin and PROP were determined by presenting, in a semi-randomised order (blind-test), series of graded aqueous solutions of each product. Subjects also tasted and rated the pleasantness/unpleasantness of 4 supra-threshold solutions of NaCl and sucrose. All subjects completed a checklist of 43 food items representative of Tunisian diet, rated in terms of flavour, cost, effect on health and prestige on a Labelled Affective Magnitude (LAM) scale. According to the underlying distribution of PROP thresholds, the subjects were separated into three categories: "non-tasters", "medium-threshold tasters", and "low-threshold tasters". Results bring out the specificity of low-threshold tasters, as exhibiting a greater taste sensitivity for most tested substances. Low-threshold taster status is also linked to higher mean food preferences ratings irrespective of sex, age and socio-cultural influences. Tasters as a group (medium-threshold tasters + low-threshold tasters) do not exhibit a higher percentage of food dislikes; however PROP sensitivity is negatively correlated with hedonic responses to NaCl solutions. These results together with the evidence of a limited set of food actually used by low-threshold tasters suggest that these subjects might have difficulties at overcoming an inherent neophobia

Identification and frequency of consumption of wild edible plants over a year in central Tunisia: a mixed-methods approach

Objective: To identify wild plants used as food and assess their frequency of consumption over a year in a region of Tunisia where agriculture is undergoing a major transformation from smallholder farming to an intensive high-input agricultural system. Design: Qualitative ethnobotanical study followed by a survey of women's frequency of consumption of wild plants conducted using FFQ at quarterly intervals. Setting: Sidi Bouzid governorate of central Tunisia. Participants: Mixed-gender group of key informants (n 14) and focus group participants (n 43). Survey sample of women aged 20-49 years, representative at governorate level (n 584). Results: Ethnobotanical study: thirty folk species of wild edible plants corresponding to thirty-five taxa were identified by key informants, while twenty folk species (twenty-five taxa) were described by focus groups as commonly eaten. Population-based survey: 98 % of women had consumed a wild plant over the year, with a median frequency of 2 d/month. Wild and semi-domesticated fennel (Foeniculum vulgare Mill. and Anethum graveolens) was the most frequently consumed folk species. Women in the upper tertile of wild plant consumption frequency were more likely to be in their 30s, to live in an urban area, to have non-monetary access to foods from their extended family and to belong to wealthier households. Conclusions: In this population, wild edible plants, predominantly leafy vegetables, are appreciated but consumed infrequently. Their favourable perception, however, offers an opportunity for promoting their consumption which could play a role in providing healthy diets and mitigating the obesity epidemic that is affecting the Tunisian population

Developing national obesity policy in middle-income countries: a case study from North Africa

Background The prevalence of overweight and obesity is a rapidly growing threat to public health in both Morocco and Tunisia, where it is reaching similar proportions to high-income countries. Despite this, a national strategy for obesity does not exist in either country. The aim of this study was to explore the views of key stakeholders towards a range of policies to prevent obesity, and thus guide policy makers in their decision making on a national level. Methods Using Multicriteria Mapping, data were gathered from 82 stakeholders (from 33 categories in Morocco and 36 in Tunisia) who appraised 12 obesity policy options by reference to criteria of their own choosing. Results The feasibility of policies in practical or political terms and their cost were perceived as more important than how effective they would be in reducing obesity. There was most consensus and preference for options targeting individuals through health education, compared with options that aimed at changing the environment, i.e. modifying food supply and demand (providing healthier menus/changing food composition/food sold in schools); controlling information (advertising controls/mandatory labelling) or improving access to physical activity. In Tunisia, there was almost universal consensus that at least some environmental-level options are required, but in Morocco, participants highlighted the need to raise awareness within the population and policy makers that obesity is a public health problem, accompanied by improving literacy before such measures would be accepted. Conclusion Whilst there is broad interest in a range of policy options, those measures targeting behaviour change through education were most valued. The different socioeconomic, political and cultural contexts of countries need to be accounted for when prioritizing obesity policy. Obesity was not recognized as a major public health priority; therefore, convincing policy makers about the need to prioritize action to prevent obesity, particularly in Morocco, will be a crucial first step

Effects of interactions between the constituents of chitosan-edible films on their physical properties

The main objective of this work was to evaluate the effect of chitosan and plasticizer concentrations and oil presence on the physical and mechanical properties of edible films. The effect of the film constituents and their in-between interactions were studied through the evaluation of permeability, opacity and mechanical properties. The effects of the studied variables (concentrations of chitosan, plasticizer and oil) were analysed according to a 2 3 factorial design. Pareto charts were used to identify the most significant factors in the studied properties (water vapour, oxygen and carbon dioxide permeability; opacity; tensile strength; elongation at break and Young's modulus). When addressing the influence of the interactions between the films' constituents on the properties above, results show that chitosan and plasticizer concentrations are the most significant factors affecting most of the studied properties, while oil incorporation has shown to be of a great importance in the particular case of transport properties (gas permeability), essentially due to its hydrophobicity. Water vapour permeability values (ranging from 1. 62 × 10 -11 to 4. 24 × 10 -11 g m -1 s -1 Pa -1) were half of those reported for cellophane films. Also the mechanical properties (tensile strength values from 0. 43 to 13. 72 MPa and elongation-at-break values from 58. 62% to 166. 70%) were in the range of those reported for LDPE and HDPE. Based on these results, we recommend the use of 1. 5% (w/w) chitosan concentration to produce films, where the oil and plasticizer proportions will have to be adjusted in a case-by-case basis according to the use intended for the material. This work provides a useful guide to the formulation of chitosan-based film-forming solutions for food packaging applications.The author MA Cerqueira is a recipient of a fellowship from Fundacao para a Ciencia e Tecnologia (FCT, SFRH/BD/23897/2005) and BWS Souza is a recipient of a fellowship from the Coordenacao Aperfeicoamento de Pessoal de Nivel Superior, Brazil (Capes, Brazil)

Trends in obesity and diabetes across Africa from 1980 to 2014: an analysis of pooled population-based studies

Background: The 2016 Dar Es Salaam Call to Action on Diabetes and Other non-communicable diseases (NCDs) advocates national multi-sectoral NCD strategies and action plans based on available data and information from countries of sub-Saharan Africa and beyond. We estimated trends from 1980 to 2014 in age-standardized mean body mass index (BMI) and diabetes prevalence in these countries, in order to assess the co-progression and assist policy formulation. Methods: We pooled data from African and worldwide population-based studies which measured height, weight and biomarkers to assess diabetes status in adults aged ≥ 18 years. A Bayesian hierarchical model was used to estimate trends by sex for 200 countries and territories including 53 countries across five African regions (central, eastern, northern, southern and western), in mean BMI and diabetes prevalence (defined as either fasting plasma glucose of ≥ 7.0 mmol/l, history of diabetes diagnosis, or use of insulin or oral glucose control agents). Results: African data came from 245 population-based surveys (1.2 million participants) for BMI and 76 surveys (182 000 participants) for diabetes prevalence estimates. Countries with the highest number of data sources for BMI were South Africa (n = 17), Nigeria (n = 15) and Egypt (n = 13); and for diabetes estimates, Tanzania (n = 8), Tunisia (n = 7), and Cameroon, Egypt and South Africa (all n = 6). The age-standardized mean BMI increased from 21.0 kg/m2 (95% credible interval: 20.3–21.7) to 23.0 kg/m2 (22.7–23.3) in men, and from 21.9 kg/m2 (21.3–22.5) to 24.9 kg/m2 (24.6–25.1) in women. The age-standardized prevalence of diabetes increased from 3.4% (1.5–6.3) to 8.5% (6.5–10.8) in men, and from 4.1% (2.0–7.5) to 8.9% (6.9–11.2) in women. Estimates in northern and southern regions were mostly higher than the global average; those in central, eastern and western regions were lower than global averages. A positive association (correlation coefficient ≃ 0.9) was observed between mean BMI and diabetes prevalence in both sexes in 1980 and 2014. Conclusions: These estimates, based on limited data sources, confirm the rapidly increasing burden of diabetes in Africa. This rise is being driven, at least in part, by increasing adiposity, with regional variations in observed trends. African countries’ efforts to prevent and control diabetes and obesity should integrate the setting up of reliable monitoring systems, consistent with the World Health Organization’s Global Monitoring System Framework

Worldwide trends in diabetes since 1980: a pooled analysis of 751 population-based studies with 4.4 million participants

BACKGROUND: One of the global targets for non-communicable diseases is to halt, by 2025, the rise in the age-standardised adult prevalence of diabetes at its 2010 levels. We aimed to estimate worldwide trends in diabetes, how likely it is for countries to achieve the global target, and how changes in prevalence, together with population growth and ageing, are affecting the number of adults with diabetes. METHODS: We pooled data from population-based studies that had collected data on diabetes through measurement of its biomarkers. We used a Bayesian hierarchical model to estimate trends in diabetes prevalence—defined as fasting plasma glucose of 7·0 mmol/L or higher, or history of diagnosis with diabetes, or use of insulin or oral hypoglycaemic drugs—in 200 countries and territories in 21 regions, by sex and from 1980 to 2014. We also calculated the posterior probability of meeting the global diabetes target if post-2000 trends continue. FINDINGS: We used data from 751 studies including 4 372 000 adults from 146 of the 200 countries we make estimates for. Global age-standardised diabetes prevalence increased from 4·3% (95% credible interval 2·4–7·0) in 1980 to 9·0% (7·2–11·1) in 2014 in men, and from 5·0% (2·9–7·9) to 7·9% (6·4–9·7) in women. The number of adults with diabetes in the world increased from 108 million in 1980 to 422 million in 2014 (28·5% due to the rise in prevalence, 39·7% due to population growth and ageing, and 31·8% due to interaction of these two factors). Age-standardised adult diabetes prevalence in 2014 was lowest in northwestern Europe, and highest in Polynesia and Micronesia, at nearly 25%, followed by Melanesia and the Middle East and north Africa. Between 1980 and 2014 there was little change in age-standardised diabetes prevalence in adult women in continental western Europe, although crude prevalence rose because of ageing of the population. By contrast, age-standardised adult prevalence rose by 15 percentage points in men and women in Polynesia and Micronesia. In 2014, American Samoa had the highest national prevalence of diabetes (>30% in both sexes), with age-standardised adult prevalence also higher than 25% in some other islands in Polynesia and Micronesia. If post-2000 trends continue, the probability of meeting the global target of halting the rise in the prevalence of diabetes by 2025 at the 2010 level worldwide is lower than 1% for men and is 1% for women. Only nine countries for men and 29 countries for women, mostly in western Europe, have a 50% or higher probability of meeting the global target. INTERPRETATION: Since 1980, age-standardised diabetes prevalence in adults has increased, or at best remained unchanged, in every country. Together with population growth and ageing, this rise has led to a near quadrupling of the number of adults with diabetes worldwide. The burden of diabetes, both in terms of prevalence and number of adults affected, has increased faster in low-income and middle-income countries than in high-income countries. FUNDING: Wellcome Trust

Development and Sustainability of National Food Composition Databases for use in Dietary Monitoring and Public Health Nutrition in the Eastern Mediterranean Region

Background:Similar to Western Countries, the Eastern Mediterranean Region (EMR) also presents major public health issues associated with the increased consumption of sugar, fat (saturated fatty acids, trans fatty acids), salt. Therefore, one of the policies of the World Health Organization’s (WHO) EMRO is to reduce the intake of these, to address the risk of obesity and non-communicable diseases such as diabetes, cardiovascular disease and cancer. In order to do this, access to updated, standardized, harmonized food composition data (FCD) is essential. Aims: Objectives within this Medical Research Council GCRF project, working jointly with WHO–EMRO, are to assess the status of national FCD and to provide training and capacity development in the use of improved standardized methodologies to update FCD as well as dietary intake methods, use of suitable biomarkers of nutritional value and to determine health outcomes in the low- and middle-income countries (LMIC) of this region. By identifying specific regional needs for FCD compilation, detailed training workshops can be developed to enable the production of vital high-quality harmonised data in the EMR including: Iran, Iraq, Pakistan, Kuwait, Tunisia, Morocco, Sudan, Egypt, Jordan together with Mauritania. This capacity building will lead to the development and sustainability of up-to-date national and regional FCD for use in dietary monitoring assessment in food and nutrient intakes. Methods: Training needs were identified, and short-term scientific missions organized for researchers via training, knowledge exchange workshops and short-term exchange of researchers. Training at CAPNUTRA (Serbia) and INNTA (Tunisia) included the use of improved standardized methodologies for food composition and food intake for 7 EMR countries leading to development of national FCD, enabling upload onto the EuroFIR data platform. A 3-week training course on analytical methods was carried out at INSA (Portugal) for analysts from Egypt, Jordan and Sudan. Key findings: A total of 45 participants from 13 countries including 10 EMR and 3 invited West African countries attended 5 workshops and training exchanges. Training topics included: value documentation and quality assessment; food composition data tools (Food Composition And System Environment (FoodCASE), Diet assess and Plan (DAP), Nutritics; food classification and description of composite dishes, recipe calculation approaches; use of yield and retention factors; EuroFIR e-learning tools and case studies; laboratory food analysis (vitamins A, B1, B2, C, D2, D3 and E, fatty acids, amino acids, minerals, fibre); quality management system; food metrology principles; validation of chromatographic methods; and food label legislation. 6 countries have imported their FCD, as open access, into the EuroFIR FoodEXplorer platform. The WHO-EMRO jointly with MRC GCRF project funded and mobilized research institutions in over 10 countries, with more focus on identifying traditional dishes and micronutrients. Conclusions and project Implications: The use of improved standardized methodologies for food composition and dietary intake will produce robust measurements that will reinforce dietary monitoring and policy in LMIC. The capacity building from this project has led to searchable national food composition data from developing/emerging countries being made available in an open access form for the first time. WHO-EMRO, is funding further updates of FCD tables in Jordan, Lebanon, Oman, Sudan, Tunisia, Morocco, Pakistan, Iran Egypt, and UAE, with the focus on identifying TFA, SFA, salt and sugar in addition to micronutrients.Project supported by Global Challenges Research Funds (UK) and Medical Research Council (MR/R019576/1), is grateful to WHO EMRO.info:eu-repo/semantics/publishedVersio