Common sources and estimated intake of plant sterols in the Spanish diet

Plant sterols (PS) are minor lipid components of plants, which may have potential health benefits, mainly based in their cholesterol-lowering effect. The aim of this study was to determine the composition and content of PS in plant-based foods commonly consumed in Spain and to estimate the PS intake in the Spanish diet. For this purpose, the determination of PS content, using a modern methodology to measure free, esterified, and glycosidic sterol forms, was done. Second, an estimation of the intake of PS, using the Spanish National Food Consumption data, was made. The daily intake per person of PS--campesterol, beta-sitosterol, stigmasterol, and stigmastanol--in the Spanish diet was estimated at 276 mg, the largest component being beta-sitosterol (79.7%). Other unknown compounds, tentatively identified as PS, may constitute a considerable potential intake (99 mg). When the daily PS intake among European diets was compared in terms of campesterol, beta-sitosterol, stigmasterol, and stigmastanol, the PS intake in the Spanish diet was in the same range of other countries such as Finland (15.7% higher) or The Netherlands (equal). However, some qualitative differences in the PS sources were detected, that is, the predominant brown bread and vegetable fat consumption in the northern diets versus the white bread and vegetable oil consumption in the Spanish diet. These differences may help to provide a link between the consumption of PS and healthy effects of the diet.     

Assessment of intake inadequacy and food sources of zinc of people in China

OBJECTIVES: To assess the intake inadequacy and food sources of zinc of people in China. DESIGN AND SUBJECTS: Diets of 68 962 subjects aged 2-101 years (urban 21 103, rural 47,859) in the 2002 China National Nutrition and Health Survey were analysed. Dietary intake was assessed using 24-hour recall for three consecutive days. Zinc intake inadequacy was calculated based on values suggested by the World Health Organization. RESULTS: The median zinc intake ranged from 4.9 mg day- 1 (urban girls, 2-3 years) to 11.9 mg day-1 (rural males, 19+ years). The zinc density of urban residents (2-3 to 19+ years) was 5.0-5.3 mg day-1 (1000 kcal)-1, significantly higher than that of their rural counterparts (4.7-4.8 mg day-1 (1000 kcal)-1). Differences in food sources of zinc from cereal grains (27.4-45.1 vs. 51.6-63.2%) and animal foods (28.4-54.8 vs. 16.8-30.6%) were found between urban and rural residents. Zinc from vegetables and fruits (8.2-13.8 vs. 9.7-12.4%) and legumes (1.3-3.3 vs. 2.5-3.4%) was comparable between urban and rural residents. The proportion of zinc intake inadequacy ranged between 2.8% (urban females, 19+ years) and 29.4% (rural lactating women). Rural residents had higher proportions of zinc intake inadequacy than their urban counterparts. Significantly higher proportions of zinc inadequacy were found in the category of phytate/zinc molar ratio >15 for both rural and urban residents. CONCLUSIONS: About 20% of rural children are at risk of inadequate zinc intake, with phytate as a potential important inhibitor. Moreover, lactating women are also considered a vulnerable group.     

Lead dietary intake in a Spanish population (Canary Islands)

For most people diet is the main route of exposure to trace metals, so information about dietary intake is also important to assess risks to human health for these elements. The purpose of this study was to determine the levels of Pb in the foods and drinks of highest consumption in the authors' our community to estimate daily intakes of Pb for each of the seven Canary Islands. Four hundred and twenty samples were analyzed using GFAAS. The total Pb intake of the Canarian population is 72.8 microg/day, 29.12% (for a person of 70 kg body weight) of the provisional tolerable weekly intake limit of 25 microg/kg fixed by the FAO/WHO. The island that presents the highest lead intake is La Gomera, followed by Lanzarote, Tenerife, and Gran Canaria islands. These four islands present a lead dietary intake over the mean Pb intake for the whole archipelago. The islands with lower Pb intakes are La Palma and Fuerteventura, with intakes under 70 microg/day. These results have also been compared with the values found for other national and international communities.     

Changes in carotenoid intake from fruit and vegetables in the Spanish population over the period 1964-2004

OBJECTIVE: To assess changes in carotenoid intake based on the variations in the consumption of fresh fruit and vegetables in the Spanish population over the period 1964-2004. DESIGN: Consumption data of fresh fruit and vegetables from Family Budget Surveys carried out in 1964, 1980, 1990 and 2004. Consumption data (g per person per day) accounted for >90% of fruit and vegetable consumption at each time point. Quality controlled high-performance liquid chromatography analysis of the carotenoid composition of Spanish fruit and vegetable was used. SUBJECTS: Randomly selected, private households throughout Spain (20,800 households in 1964, 30,311 households in 1980, 21,155 households in 1990 and 6000 households in 2004). Twelve vegetables and 16 fruits representing 89-96% of the total consumption of fresh fruit and vegetables were used. RESULTS: Individual consumption of fruit and vegetables has changed over this period, altering the total and individual intake of carotenoids. Total carotenoid intake increased from 2.5 mg per person per day in 1964 to 4.1 mg per person per day in 1990, with a decrease to 3.3 mg per person per day in 2004. These increments are due to an increase in lycopene, alpha- and beta-carotene, while a decrease in lutein and zeaxanthin is observed during the last decade. A continuous and consistent decrease in the relative contribution of lutein in the diet is observed over the period studied. CONCLUSION: Although the consumption of fruit and vegetables is still consistent with a Mediterranean-type pattern, modifications in the consumption of individual fruits and vegetables have provoked changes in total and specific carotenoid intake with potential relevance in human health.     

Multivariate and spatial analysis of heavy metal sources and variations in a large old antimony mine, China

Purpose

Contaminations by multiple heavy metals in antimony (Sb) mines produce serious environmental and health problems; however, the spatial variations in various heavy metals relative to the sources and transportation of Sb have rarely been documented. To resolve this problem, we conducted a survey in an old Sb mine in Xikuangshan (XKS), China, to investigate the similarities and differences among the sources and diffusion characteristics of the heavy metals that were present as well as the factors influencing these patterns.

Materials and methods

A total of 71 surface soil samples were collected in the central study area, which has a history of intensive mining and smelting activities, as well as in surrounding areas at different distances from the central mine and with different coverage/landscape/land use characteristics; we refer to these areas as the central mining subarea, tailing subarea in the southwest, forestry subarea in the southeast, grass subarea at the northern edge of the study area and vegetation subarea at the southern edge. Multivariate and spatial analyses were performed to explore the correlations and patterns of variation of various heavy metals.

Results and discussion

Hg and Cd were evidently elevated in XKS, whereas the concentrations of As, Pb and Zn were moderate and that of Cr was comparable to the background values. Moderate correlations were found for Sb–As and Hg–Cd, and strong correlations were observed for Pb, Zn, Cd and Cr. The southeast direction was associated with the strongest spatial autocorrelation for Sb, which is consistent with the prevailing wind direction in XKS; the optimal directions for Zn and Cd were similar and indicated the transfer of Zn and Cd contamination from subareas with high levels to those with low levels, significantly affecting the spatial distribution of these metals in XKS.

Conclusions

Our results highlight the importance of the effect of wind on the diffusion of Sb in XKS. The co-contamination of Hg and Cd with Sb is widespread in XKS due to the presence of Hg and Cd in Sb-containing ores.     

Microbial population dynamics related to temporal variations in nitrification in three arable fields

It seems possible that soil potential nitrification rates (PNRs) are determined by the size and structure of both the eubacterial and nitrifier populations. We have examined this possibility by comparing the structure of the eubacterial community with the subcomponents and dynamics of the ammonium‐oxidizer population, within and between three arable fields. PNRs were significantly different between the three fields and also showed significantly different temporal patterns within each field. The use of eubacterial primers in polymerase chain reaction–denaturing gel gradient electrophoresis (PCR–DGGE) analyses indicated that the bacterial community structure in each field was significantly different from that in the others, and that the bacterial components of these communities changed with time through the season. In contrast, PCR–DGGE analyses specific to ammonium oxidizers suggested that the populations in all three fields were similar in types and did not vary with time. Competitive PCR suggested that there were large and biologically significant differences in the size of the nitrifier population between the three fields, but that within each individual field populations did not change over time. Sequencing identified the ammonium oxidizers in the Nitrosospira spp. cluster. There was also no relation between the size of the nitrifier populations and PNR. Functional expression, as PNR, apparently responded to changes in eubacterial community structure.     

Plasma micronutrients are associated with dietary intake and environmental tobacco smoke exposure in a paediatric population

BACKGROUND: While adult populations have been well described in terms of nutritional status, such as the concentration of nutrient biomarkers, little work has been done in healthy paediatric populations. OBJECTIVE: The primary objective of this analysis was to explore the determinants of plasma micronutrients in a group of healthy infants and children. DESIGN: The Diabetes Autoimmunity Study in the Young (DAISY) has enrolled 1433 newborns at increased risk for type 1 diabetes in Denver, Colorado. A representative random sample of 257 children from the DAISY cohort between the ages of 9 months and 8 years with a total of 815 clinic visits over time was used in this analysis. Annual dietary intake was assessed over time with Willett food-frequency questionnaires that were validated in this population. Environmental tobacco smoke (ETS) was assessed using a validated survey. Plasma samples were tested for vitamins, carotenoids and total lipids. Predictors of plasma micronutrients were evaluated using mixed models for longitudinal data, while adjusting for age, human leukocyte antigen genotype, type 1 diabetes family history and other potential confounders and covariates. RESULTS: Increased micronutrient intake was associated with increased levels of their respective plasma nutrient, with the exception of gamma-tocopherol. Independent of dietary intake, levels of alpha- and beta-carotene and beta-cryptoxanthin were significantly lower, and gamma-tocopherol was significantly higher, in children who were exposed to ETS. CONCLUSION: Dietary intake predicts plasma micronutrient levels. Exposure to ETS potentially could have negative health effects in this young population.     

A multilevel study of socio-economic inequalities in food choice behaviour and dietary intake among the Dutch population: the GLOBE study

OBJECTIVE: To examine the influence of individual- and area-level socio-economic characteristics on food choice behaviour and dietary intake. SETTING: The city of Eindhoven in the south-east Netherlands. DESIGN: A total of 1339 men and women aged 25-79 years were sampled from 85 areas (mean number of participants per area = 18.4, range 2-49). Information on socio-economic position (SEP) and diet was collected by structured face-to-face interviews (response rate 80.9%). Individual-level SEP was measured by education and household income, and area-level deprivation was measured using a composite index that included residents' education, occupation and employment status. Diet was measured on the basis of (1) a grocery food index that captured compliance with dietary guidelines, (2) breakfast consumption and (3) intakes of fruit, total fat and saturated fat. Multilevel analyses were performed to examine the independent effects of individual- and area-level socio-economic characteristics on the dietary outcome variables. RESULTS: After adjusting for individual-level SEP, few trends or significant effects of area deprivation were found for the dietary outcomes. Significant associations were found between individual-level SEP and food choice, breakfast consumption and fruit intake, with participants from disadvantaged backgrounds being less likely to report food behaviours or nutrient intakes consistent with dietary recommendations. CONCLUSIONS: The findings suggest that an individual's socio-economic characteristics play a more important role in shaping diet than the socio-economic characteristics of the area in which they live. In this Dutch study, no independent influence of area-level socio-economic characteristics on diet was detected, which contrasts with findings from the USA, the UK and Finland.     

Antioxidant activity of the flavonoid hesperidin in chemical and biological systems

The antioxidant hesperidin, a major flavonoid in sweet orange and lemon, was evaluated using chemical and biological systems. The chemical assay evaluates the hesperidin capacity to sequester 1,1-diphenyl-2-picrylhydrazyl (DPPH*). Biological studies were done using the eukaryotic cells of superoxide-dismutase proficient and deficient strains of Saccharomyces cerevisiae treated with hesperidin and the stressing agents hydrogen peroxide or paraquat (methylviologen; 1,1'-dimethyl-4,4'-bipyridinium dichloride). Hesperidin was able to reduce significantly the level of the free radical DPPH* with similar efficacy of trolox (positive control). When the yeast cells were exposed to the flavonoid hesperidin before the stressing agents, there was a significant increase in the survival of all strains. Paraquat induced higher catalase and superoxide dismutase than did hydrogen peroxide, which only increased catalase activity. Previous addition of hesperidin to these treatments was able to reduce significantly both enzymatic levels. These observations clearly demonstrate that hesperidin provides strong cellular antioxidant protection against the damaging effects induced by paraquat and peroxide hydrogen.