There is increasing interest in vitamin D and its possible health effects. The aims of the present overview are to summarise the research on common diseases for which there is substantial evidence on vitamin D, identify diseases where vitamin D may be beneficial and discuss the public health implications of these findings.

Literature search of PubMed for the years 2000 to 2010 to identify cohort studies with baseline measures of 25-hydroxyvitamin D (25(OH)D) and randomised controlled trials (RCT) of vitamin D supplementation in relation to fractures, colorectal cancer, CVD and all-cause mortality. Risk ratios of disease from comparisons between 25(OH)D quantiles in these studies were summarised using RevMan software version 5·1 (The Nordic Cochrane Centre, Copenhagen).

Community-based samples recruited into cohort studies from many countries.

Older men and women, mostly above 50 years of age.

When comparing the lowest 25(OH)D category with the highest (or reference), the pooled risk ratio (95 % CI) was: 1·34 (1·13, 1·59) for fractures from nine studies; 1·59 (1·30, 1·95) for colorectal cancer from nine studies; 1·35 (1·17, 1·56) for CVD from twelve studies; and 1·42 (1·23, 1·63) for all-cause mortality from twelve studies.

Cohort studies show that baseline 25(OH)D levels predict increased risk of fractures, colorectal cancer, CVD and all-cause mortality. These associations are weak and could be explained by confounding variables such as obesity and physical activity. Because of their potential public health significance, RCT using vitamin D doses ≥50 μg/d are required to determine whether vitamin D protects against these diseases.

To estimate the prevalence of inadequate nutrient intake among adolescents and the association between socio-economic variables and nutritional status.

Cross-sectional study with a population-based sample.

The usual nutrient intake distribution was estimated using the Iowa State University method. The Estimated Average Requirement cut-off point method was used to determine the proportion of adolescents with inadequate intake for each nutrient, according to sex, income, parental educational level and nutritional status.

Twenty-four-hour dietary recalls were applied in 525 male and female Brazilian adolescents aged 14–18 years.

The highest prevalence of inadequate nutrient intake was observed for vitamin E (99 % in both sexes). For male and female adolescents, the prevalence of inadequate intake was: Mg, 89 % and 84 %; vitamin A, 78 % and 71 %; vitamin C, 79 % and 53 %; and vitamin B6, 21 % and 33 %, respectively. The prevalence of inadequate intake for niacin, thiamin, riboflavin, Se, Cu and vitamin B12 was <15 %. Individuals in the lower income and lower parental educational level strata had the highest risk of having inadequate intake for P, riboflavin and vitamins A, B6 and B12. Compared with non-overweight individuals, overweight individuals had a higher risk of inadequate intake for Mg, vitamin A, P, thiamin and riboflavin.

The present study found a high prevalence of inadequate intake of nutrients that are recognised as being protective against chronic diseases. Adolescents in the lower income and lower parental educational level strata were less likely to have their nutrient intake requirements met.

To analyse dietary compliance with WHO/FAO nutritional objectives, identify food subgroups that contribute to discrepancies between dietary intakes and recommendations, and assess food patterns and risk factor profiles at common nutritional targets.

The study was a population-based, cross-sectional assessment of the dietary patterns of Tehranian adults. Usual dietary intake was assessed in relation to common nutritional targets of public health (fat, saturated fat, dietary fibre, fruit and vegetables) using a validated FFQ. Metabolic syndrome (MetS) risk factors were diagnosed based on the Iranian-modified diagnostic criteria of the National Cholesterol Education Program Adult Treatment Panel III.

The Tehran Lipid and Glucose Study (2005–2008).

A total of 2510 individuals (1121 men and 1389 women), aged between 19 and 70 years.

Generally, 68·5 % of total grain ounce-equivalents were derived from refined grains, with rice making up 36·6 % of all grains consumed. Solid fat (61·1 %) contributed more to discretionary energy than did added sugars (38·9 %). There was a twofold difference in fruit and vegetable consumption between the lowest and highest quartile categories of dietary fibre intake. The probability of having MetS was significantly lower in the highest quartile of fibre intake v. the lowest (OR = 0·69, 95 % CI 0·58, 0·84 v. OR = 0·92, 95 % CI 0·80, 1·03; P -trend < 0·001), whereas it was higher in the highest quartile of SFA intake v. the lowest (OR = 0·92, 95 % CI 0·78, 0·98 v. OR = 0·71, 95 % CI 0·62, 0·89; P-trend = 0·01).

Complying with common nutritional targets of public health is inversely associated with MetS risk factors in Tehranian adults. These results may initiate measures for future development of regional food-based dietary guidelines.

The present study aimed to analyse changes in meal pattern among Norwegian children from 2001 to 2008 in general; to analyse associations between meal pattern and gender, parental educational level and number of parents in the household; and to analyse the association between intake of unhealthy snacks, meal pattern and the mentioned variables.

Within the Fruits and Vegetables Make the Marks (FVMM) project, two cross-sectional studies were conducted, one in 2001 and one in 2008, where participants from the same schools filled in a questionnaire on meals eaten the previous day.

Participants were 6th and 7th grade pupils, n 1488 in 2001 and n 1339 in 2008.

Twenty-seven elementary schools in two Norwegian counties.

There were no significant changes in children's meal pattern from 2001 to 2008. For both years more than 90 % of the participants reported that they had breakfast yesterday, while 95 % had lunch, 94 % had dinner and 82 % had supper. More girls than boys reported that they had lunch yesterday (96 % v. 94 %, P = 0·03). More children with higher v. lower educated parents reported that they had breakfast yesterday (93 % v. 88 %, P < 0·001). More children living with two parents v. one parent had breakfast (93 % v. 88 %, P = 0·001) and lunch yesterday (97 % v. 93 %, P < 0·001).

There were no changes in meal pattern from 2001 to 2008 among Norwegian children. Characteristics associated with skipping meals were living in a one-parent family and having lower educated parents.

Family meals are an important ritual in contemporary societies and many studies have reported associations of family meals with several biopsychosocial outcomes among children and adolescents. However, few representative analyses of family meals have been conducted in samples of adults, and adults may differ from young people in predictors and outcomes of family meal consumption. We examined the prevalence and predictors of adult family meals and body weight outcomes.

The cross-sectional 2009 Cornell National Social Survey (CNSS) included questions about the frequency of family meals, body weight as BMI and sociodemographic characteristics.

The CNSS telephone survey used random digit dialling to sample individuals.

We analysed data from 882 adults living with family members in a nationally representative US sample.

Prevalence of family meals among these adults revealed that 53 % reported eating family meals seven or more times per week. Predictive results revealed that adults who more frequently ate family meals were more likely to be married and less likely to be employed full-time, year-round. Outcome results revealed that the overall frequency of family meals among adults was not significantly associated with any measure of body weight. However, interaction term analysis suggested an inverse association between frequency of family meals and BMI for adults with children in the household, and no association among adults without children.

These findings suggest that family meals among adults are commonplace, associated with marital and work roles, and marginally associated with body weight only in households with children.

To compare food consumption during television (TV) viewing among adolescents who watched >2 h/d v. ≤2 h/d; and to examine the association between sociodemographic variables (age, gender and socio-economic status (SES)) and the consumption of energy-dense foods and drinks during TV viewing.

The data are part of the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) cross-sectional survey. Data on time watching TV, types of foods and drinks consuming during TV viewing and parental SES (parental education, parental occupation and family affluence) were measured by questionnaires completed by adolescents. Binary logistic regression tested the association between energy-dense foods and drinks and (i) sociodemographic variables and (ii) TV time.

Ghent (Belgium), Heraklion (Greece), Pecs (Hungary) and Zaragoza (Spain).

Girls (n 699) and boys (n 637) aged 12·5–17·5 years.

Boys reported more frequent consumption of beer and soft drinks whereas girls selected more fruit juice, water, herbal infusions and sweets (all P ≤ 0·05). Watching TV for >2 h/d was associated with the consumption of energy-dense foods and drinks. Girls whose mothers achieved the lowest education level had an adjusted OR of 3·22 (95 % CI 1·81, 5·72) for the consumption of energy-dense drinks during TV viewing v. those whose mothers had the highest educational level.

Excessive TV watching may favour concurrent consumption of energy-dense snacks and beverages. Adolescents from low-SES families are more likely to consume unhealthy drinks while watching TV.

To identify and characterize dietary patterns in Lebanon and assess their association with sociodemographic factors, BMI and waist circumference (WC).

A cross-sectional population-based survey. In a face-to-face interview, participants completed a brief sociodemographic and semiquantitative FFQ. In addition, anthropometric measurements were obtained following standard techniques. Dietary patterns were identified by factor analysis. Multivariate linear regression was used to assess determinants of the various patterns and their association with BMI and WC.

National Nutrition and Non-Communicable Disease Risk Factor Survey (2009), Lebanon.

A nationally representative sample of 2048 Lebanese adults aged 20–55 years.

Four dietary patterns were identified: ‘Western’, ‘Traditional Lebanese’, ‘Prudent’ and ‘Fish and alcohol’. Factor scores of the identified patterns increased with age, except for the Western pattern in which a negative association was noted. Women had higher scores for the prudent pattern. Adults with higher levels of education had significantly higher scores for the prudent pattern. The frequency of breakfast consumption was significantly associated with scores of both traditional Lebanese and prudent patterns. Multivariate-adjusted analysis revealed a positive association between scores of the Western pattern and the BMI and WC of study participants.

The findings show the presence of four distinct dietary patterns in the Lebanese population, which were associated with age, sex, education and meal pattern. Only the Western pattern was associated with higher BMI.

To describe the association of socio-economic, demographic and lifestyle characteristics with three eating patterns identified among low-income adults living in the Rio de Janeiro metropolitan area, Brazil.

Data were obtained in a population-based cross-sectional study. The analysed patterns were: (i) ‘Mixed’, in which diverse foods had similar factor loadings; (ii) ‘Western’, which included items with high energy density; and (iii) ‘Traditional’, which relied in rice and beans, traditional staple foods in Brazil. Hierarchical logistic analysis was performed to estimate the association between the independent variables and each one of the dietary patterns. The variables that presented statistical significance <0·20 in the univariate analysis (χ2 test) were included in the multivariate models.

Duque de Caxias, a low-income area in the Rio de Janeiro metropolitan region, Brazil.

Adults (n 1009) aged 20 to 65 years (339 men and 670 women).

The ‘Mixed’ pattern was positively associated with smoking (OR = 1·58, 95 % CI 1·00, 2·48 for current smoking v. those who never smoked). The ‘Western’ pattern was positively associated with family income (OR = 3·00, 95 % CI 1·81, 4·97 for those with monthly per capita family income ≥1·0 v. <0·5 times the official Brazilian minimum wage) and inversely associated with family food insecurity (OR = 0·55, 95 % CI 0·36, 0·84). The ‘Traditional’ pattern was associated with family food insecurity (OR = 1·79, 95 % CI 1·27, 2·51).

The results support previous findings relating improvement in economic conditions to reduced adherence to the traditional Brazilian food consumption pattern based on the combination of rice and beans.

To identify food acquisition patterns in Brazil and relate them to the sociodemographic characteristics of the household.

A cross-sectional national Household Budget Survey (HBS). Principal component factor analysis was used to derive food patterns (factors) on the basis of the acquisition of food classified into thirty-two food groups.

The source of data originates from the 2002–2003 HBS carried out by the Brazilian Institute of Geography and Statistics between June 2002 and July 2003 using a representative sample of all Brazilian households.

A total of 48 470 households allocated into 443 strata of households that were geographically and socio-economically homogeneous as a study unit.

We identified two patterns of food acquisition. The first, named ‘dual’, was characterized by dairy, fruit, fruit juice, vegetables, processed meat, soft drinks, sweets, bread and margarine, and by inverse correlations with Brazilian staple foods. In contrast, the second pattern, named ‘traditional’, was characterized by rice, beans, manioc, flour, milk and sugar. The ‘dual’ pattern was associated with higher household educational level, income and the average age of adults on the strata, whereas the ‘traditional’ presented higher loadings in less-educated households and in the rural setting.

Dietary patterns described here suggest that policies and programmes to promote healthy eating need to consider that healthy and non-healthy foods may be integral in the same pattern.

To identify predominant dietary patterns among Hispanic women and to determine whether adherence to dietary patterns is predicted by neighbourhood-level factors: linguistic isolation, poverty rate and the retail food environment.

Cross-sectional analyses of predictors of adherence to dietary patterns identified from principal component analysis of data collected using the Study of Women's Health Across the Nation FFQ. Census data were used to measure poverty rates and the percentage of Spanish-speaking families in the neighbourhood in which no person aged ≥14 years spoke English very well (linguistic isolation) and the retail food environment was measured using business listings data.

New York City.

A total of 345 Hispanic women.

Two major dietary patterns were identified: a healthy dietary pattern loading high for vegetables, legumes, potatoes, fish and other seafood, which explained 17 % of the variance in the FFQ data and an energy-dense dietary pattern loading high for red meat, poultry, pizza, french fries and high-energy drinks, which explained 9 % of the variance in the FFQ data. Adherence to the healthy dietary pattern was positively associated with neighbourhood linguistic isolation and negatively associated with neighbourhood poverty. Presence of more fast-food restaurants per square kilometre in the neighbourhood was significantly associated with lower adherence to the healthy diet. Adherence to the energy-dense dietary pattern was inversely, but not significantly, associated with neighbourhood linguistic isolation.

These results are consistent with the hypothesis that living in immigrant enclaves is associated with healthy dietary patterns among Hispanics.

There is increasing evidence that the school food environment contributes to childhood obesity and health in various locations. We investigated the influence of fast-food stores and convenience food stores (FS and CS, respectively) on growth and body composition in a range of residential densities for North-east Asian food culture.

Anthropometrics and birth weight of schoolchildren were obtained. Geocoded mapping of schools and food outlets was conducted. Multivariable linear regression models, adjusted for father's ethnicity and education, as well as for household income, pocket money, birth weight, physical activity, television watching, food quality and region, were used to predict body composition from school food environments.

Elementary schools and school neighbourhoods in 359 townships/districts of Taiwan.

A total of 2283 schoolchildren aged 6–13 years from the Elementary School Children's Nutrition and Health Survey in Taiwan conducted in 2001–2002.

Remote and socially disadvantaged locations had the highest prevalence of lower weight, BMI, waist circumference and triceps skinfold thickness. Food store densities, FS and CS, were highest in urban Taiwan and lowest in remote Taiwan. In the fully adjusted models, FS densities predicted weight and BMI in boys; there was a similar association for waist circumference, except when adjusted for region. FS densities also predicted height for girls. Except for weight and BMI in boys, CS did not have effects evident with FS for either boys or girls.

A high FS density, more than CS density, in Taiwan increased the risk of general (BMI) and abdominal (waist circumference) obesity in boys and stature in girls. These findings have long-term implications for chronic disease in adulthood.

To examine associations between various measures of the food environment and BMI percentile among youth.

Cross-sectional, observational.

Pitt County, eastern North Carolina.

We extracted the electronic medical records for youth receiving well child check-ups from January 2007 to June 2008. We obtained addresses for food venues from two secondary sources and ground-truthing. A geographic information systems database was constructed by geocoding home addresses of 744 youth and food venues. We quantified participants’ accessibility to food venues by calculating ‘coverage’, number of food venues in buffers of 0·25, 0·5, 1 and 5 miles (0·4, 0·8, 1·6 and 8·0 km) and by calculating ‘proximity’ or distance to the closest food venue. We examined associations between BMI percentile and food venue accessibility using correlation and regression analyses.

There were negative associations between BMI percentile and coverage of farmers’ markets/produce markets in 0·25 and 0·5 mile Euclidean and 0·25, 0·5 and 1 mile road network buffers. There were positive associations between BMI percentile and coverage of fast-food and pizza places in the 0·25 mile Euclidean and network buffers. In multivariate analyses adjusted for race, insurance status and rural/urban residence, proximity (network distance) to convenience stores was negatively associated with BMI percentile and proximity to farmers’ markets was positively associated with BMI percentile.

Accessibility to various types of food venues is associated with BMI percentile in eastern North Carolina youth. Future longitudinal work should examine correlations between accessibility to and use of traditional and non-traditional food venues.

To investigate whether exposure to fast-food outlets and supermarkets is socio-economically patterned in the city of Copenhagen.

The study was based on a cross-sectional multivariate approach to examine the association between the number of fast-food outlets and supermarkets and neighbourhood-level socio-economic indicators. Food business addresses were obtained from commercial and public business locators and geocoded using a geographic information system for all neighbourhoods in the city of Copenhagen (n 400). The regression of counts of fast-food outlets and supermarkets v. indicators of socio-economic status (percentage of recent immigrants, percentage without a high-school diploma, percentage of the population under 35 years of age and average household income in Euros) was performed using negative binomial analysis.

Copenhagen, Denmark.

The unit of analysis was neighbourhood (n 400).

In the fully adjusted models, income was not a significant predictor for supermarket exposure. However, neighbourhoods with low and mid-low income were associated with significantly fewer fast-food outlets. Using backwise deletion from the fully adjusted models, low income remained significantly associated with fast-food outlet exposure (rate ratio = 0·66–0·80) in the final model.

In the city of Copenhagen, there was no evidence of spatial patterning of supermarkets by income. However, we detected a trend in the exposure to fast-food outlets, such that neighbourhoods in the lowest income quartile had fewer fast-food outlets than higher-income neighbourhoods. These findings have similarities with studies conducted in the UK, but not in the USA. The results suggest there may be socio-economic factors other than income associated with food exposure in Europe.

To examine the relationship between homestead food production and night blindness among pre-school children in rural Bangladesh in the presence of a national vitamin A supplementation programme.

A cross-sectional study.

A population-based sample of six rural divisions of Bangladesh assessed in the Bangladesh Nutrition Surveillance Project 2001–2005.

A total of 158 898 children aged 12–59 months.

The prevalence rates of night blindness in children among those who did and did not receive vitamin A capsules in the last 6 months were 0·07 % and 0·13 %, respectively. Given the known effect of vitamin A supplementation on night blindness, the analysis was stratified by children's receipt of vitamin A capsules in the last 6 months. Among children who did not receive vitamin A capsules in the last 6 months, the lack of a home garden was associated with increased odds of night blindness (OR = 3·16, 95 % CI 1·76, 5·68; P = 0·0001). Among children who received vitamin A capsules in the last 6 months, the lack of a home garden was not associated with night blindness (OR = 1·28, 95 % CI 0·71, 2·31; P = 0·4).

Homestead food production confers a protective effect against night blindness among pre-school children who missed vitamin A supplementation in rural Bangladesh.

Although previous research has shown limited availability of healthy food in low-income urban neighbourhoods, the association between food source use and food-purchasing patterns has not yet been examined. We explored food-purchasing patterns in the context of food source use and food source access factors in low-income areas of Baltimore City.

Cross-sectional survey.

Predominantly low-income neighbourhoods in East and West Baltimore City.

A total of 175 low-income African-American adult residents.

Supermarkets and corner stores were the most frequently used food sources. Walking was the main form of transportation used by 57 % of all respondents, 97 % of corner-store shoppers and 49 % of supermarket shoppers. Multiple linear regression models adjusting for demographic factors, type of food source used and transportation type found that corner-store use was associated with obtaining more unhealthy food (P = 0·005), whereas driving to the food source was associated with obtaining more healthy food (P = 0·012).

The large number of corner stores compared with supermarkets in low-income neighbourhoods makes them an easily accessible and frequently used food source for many people. Interventions to increase the availability and promotion of healthy food in highly accessed corner stores in low-income neighbourhoods are needed. Increased access to transportation may also lead to the use of food sources beyond the corner store, and to increased healthy food purchasing.

To investigate the food shopping habits of older adults in the UK and explore their potential associations with selected health-related indicators.

A cross-sectional study including objectively measured physical activity levels, BMI, physical function and self-reported health status and dietary intake.

Bristol, UK.

A total of 240 older adults aged ≥70 years living independently.

Mean age was 78·1 (sd 5·7) years; 66·7 % were overweight or obese and 4 % were underweight. Most (80·0 %) carried out their own food shopping; 53·3 % shopped at least once weekly. Women were more likely to shop alone (P < 0·001) and men more likely to shop with their spouse (P < 0·001). Men were more likely than women to drive to food shopping (P < 0·001), with women more likely to take the bus or be driven (P < 0·001). Most reported ease in purchasing fruit and vegetables (72·9 %) and low-fat products (67·5 %); 19·2 % reported low fibre intakes and 16·2 % reported high fat intakes. Higher levels of physical function and physical activity and better general health were significantly correlated with the ease of purchasing fresh fruit, vegetables and low-fat products. Shopping more often was associated with higher fat intake (P = 0·03); higher levels of deprivation were associated with lower fibre intake (P = 0·019).

These findings suggest a pattern of food shopping carried out primarily by car at least once weekly at large supermarket chains, with most finding high-quality fruit, vegetables and low-fat products easily accessible. Higher levels of physical function and physical activity and better self-reported health are important in supporting food shopping and maintaining independence.

To investigate the prevalence and characteristics of metabolic syndrome (MetS) in a healthy elderly Croatian population.

Cross-sectional study consisting of a health check including anthropometric measures and food questionnaires as well as analysis of biochemical parameters related to MetS. The diagnostic criteria of the International Diabetes Federation (IDF) were used for diagnosis of MetS.

Four centres in continental (Virovitica and Zagreb) and Adriatic coast (Split and Omiš) regions of Croatia.

Free-living elderly persons aged 70–90 years (n 320).

Significantly lower MetS prevalence was found among participants from small urban centres compared with those from large urban centres (59·1 % v. 69·6 %; P = 0·051). Participants without MetS consumed wine more frequently (P = 0·05) than those with MetS. Compared with their peers with HDL cholesterol (HDL-C) <1·03 mmol/l, more male participants with HDL-C ≥1·03 mmol/l consumed wine (P = 0·04) or pelagic fish (P = 0·03). The prevalence of participants with TAG ≥1·7 mmol/l was higher in wine non-consumers (P = 0·05) than in wine consumers. Multivariate analysis with age and gender as covariates showed a significant inverse association of wine consumption with total cholesterol (P < 0·001), a positive association with HDL-C (P < 0·001) and a marginally inverse association with TAG (P = 0·06). In the male population, alkaline phosphatase and γ-glutamyl transferase activities were higher in participants with MetS (P < 0·05).

High MetS prevalence was observed in an elderly Croatian population. Data showed that moderate consumption of wine and/or pelagic fish has a protective role against MetS in the population studied.

To understand the barriers to farmer participation in Farm-to-Table (F2T) programmes and to identify possible solutions to these obstacles.

Cross-sectional analysis of farmer perspectives on F2T programmes.

Three service units on the Navajo Nation (Chinle, Tuba City and Fort Defiance).

Forty-four Navajo farmers.

Most participants reported that farming on the Navajo Nation is getting harder (61 %) but that it is very important to maintain Navajo farming traditions (98 %). A modest number of farmers (43 %) expressed interest in participating in an F2T programme. All farmers reported that childhood obesity was a very serious or serious problem in the Navajo Nation. The farmers expressed support for an F2T programme if key barriers to farming, including water access and pest control, could be addressed. Key barriers to participation identified included lack of fruits and vegetables to sell, sale price of crops and lack of certification of produce by the US Food and Drug Administration.

Navajo farmers are aware of the burden of childhood obesity on the Navajo Nation and feel that an F2T programme could be beneficial. To successfully implement a Farm-to-Table programme, the barriers to participation identified will need to be addressed.