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

Heavy Metals in the Environment and Health Impact

Heavy metals are among the most harmful contaminants in the ecosystems due to their persistency, bioaccumulation and high toxicity. In this chapter, we presented the sources, distribution and pathways of heavy metals in soil, water and air. The physico-chemical properties, uses, toxicity and health hazards of the purely toxic heavy metals lead, cadmium and mercury were also described. Other essential heavy metals were briefly presented and the main health effects due to their deficiency or excess were displayed in this chapter. Finally, the various methods used for the removal of heavy metals from soil and aquatic environments were discussed with a focus on nanomaterials

Food Supplementation with Vitamins and Minerals: An Overview

Vitamins are organic substances that are essential for normal metabolism, growth, development, and regulation of cell function. Mineral elements are non-organic substances. They constitute 4% of the body mass. Multivitamins and minerals are commonly used as dietary supplements to maintain good health and prevent chronic diseases. In this chapter, we described selected vitamins and minerals used as nutritional supplements. We presented their dietary sources as well as their absorption, metabolism, storage and functions in human body. We also discussed their benefits and potential harmful effects associated with deficiency or excess intake. The prevalence, recommended intakes, regulatory status and health effects of supplementation with these micronutrients were also detailed. Finally, the use of vitamins and minerals as food additives was described in this chapter

Influence of socio-economic and lifestyle factors on overweight and nutrition-related diseases among Tunisian migrants versus non-migrant Tunisians and French

<p>Abstract</p> <p>Background</p> <p>Migrant studies in France revealed that Mediterranean migrant men have lower mortality and morbidity than local-born populations for non-communicable diseases (NCDs). We studied overweight and NCDs among Tunisian migrants compared to the population of the host country and to the population of their country of origin. We also studied the potential influence of socio-economic and lifestyle factors on differential health status.</p> <p>Methods</p> <p>A retrospective cohort study was conducted to compare Tunisian migrant men with two non-migrant male groups: local-born French and Tunisians living in Tunisia, using frequency matching. We performed quota sampling (n = 147) based on age and place of residence. We used embedded logistic regression models to test socio-economic and lifestyle factors as potential mediators for the effect of migration on overweight, hypertension and reported morbidity (hypercholesterolemia, type-2 diabetes, cardiovascular diseases (CVD)).</p> <p>Results</p> <p>Migrants were less overweight than French (OR = 0.53 [0.33–0.84]) and had less diabetes and CVD than Tunisians (0.18 [0.06–0.54] and 0.25 [0.07–0.88]). Prevalence of hypertension (grade-1 and -2) and prevalence of hypercholesterolemia were significantly lower among migrants than among French (respectively 0.06 [0.03–0.14]; 0.04 [0.01–0.15]; 0.11 [0.04–0.34]) and Tunisians (respectively OR = 0.07 [0.03–0.18]; OR = 0.06 [0.02–0.20]; OR = 0.23 [0.08–0.63]).</p> <p>The effect of migration on overweight was mediated by alcohol consumption. Healthcare utilisation, smoking and physical activity were mediators for the effect of migration on diabetes. The effect of migration on CVD was mediated by healthcare utilisation and energy intake. No obvious mediating effect was found for hypertension and hypercholesterolemia.</p> <p>Conclusion</p> <p>Our study clearly shows that lifestyle (smoking) and cultural background (alcohol) are involved in the observed protective effect of migration.</p