Many health promotion educational interventions assume that increasing knowledge directly influences beliefs, intentions and behaviour, whereas research suggests that knowledge alone is insufficient for behavioural change. Social cognition frameworks such as the Theory of Reasoned Action propose a central role for beliefs and social normative influences. This Scottish study evaluates the role of knowledge and social influences (subjective norms, exposure to breast-feeding, social barriers) on beliefs and future intentions to breast-feed or bottle-feed. Social influences from family and peers are investigated.

A cross-sectional between-subjects observational design was used. A questionnaire was administered to a sample of 229 (46%) male and 267 (54%) female adolescents aged 11–18 years.

Participants completed questionnaires during lessons at three secondary schools in Central Scotland.

Knowledge about health benefits of breast-feeding was generally poor. Analyses found that perceived social barriers to breast-feeding moderated the relationship between knowledge and beliefs. More knowledge, positive beliefs and supportive subjective norms also predicted future intentions to breast-feed. Parental norms exerted greater influence than peer norms on adolescents' breast-feeding beliefs.

Knowledge and social influences are important predictors of positive breast-feeding beliefs and future intentions to breast-feed in adolescents. This has important implications for breast-feeding health promotion interventions in young people.

To examine the relationship between unintended pregnancies and prolonged breast-feeding among 18 countries on an individual and aggregated level.

Regional multivariate logistic regression analyses were conducted to examine this association based on 18 Demographic and Health Surveys conducted between 1995 and 2000.

Women who had a live child between 13 and 36 months old were included in these analyses (n = 41 353).

Regression models were adjusted for 10 covariates including child age, maternal age, pregnancy status of mother at the time of interview and parity. In 11 out of the 18 countries the odds ratio (OR) of the association between unintended pregnancies and prolonged breast-feeding was <1.0, reaching statistical significance in three countries. Pooled analyses of all 18 countries detected a significant association between unintended pregnancies and less likelihood of prolonged breast-feeding (OR = 0.90, 95% confidence interval = 0.85–0.96).

Prospective studies are needed to further understand if and how pregnancy intentions influence breast-feeding outcomes in different settings.

Breast-feeding (BF) provides the ideal food for the healthy growth and development of infants. The prevalence of BF in Lebanon shows mixed results. The present study was the first large-scale, extensive survey on BF parameters in Lebanon that aimed to explore demographic, socio-economic and other fundamental issues associated with the initiation and duration of BF by Lebanese mothers.

The survey was cross-sectional in design and administered over 10 months.

Information on all variables was collected from mothers at health centres.

Two-stage sampling was conducted to select participants. A total of 1000 participants were randomly selected. A consent form was provided to each participant. Data were collected from 830 of these.

Almost all mothers were Lebanese, married and had given birth in a hospital. About a third stated that breast milk was the first food introduced after birth. Although 55.9% started breast-feeding their newborns within a few hours after birth, and 18.3% within half an hour, 21.2% replied that they initiated BF a few days after birth. Only 4.6% of the mothers replied that they never breast-fed their infant. Timing of initiation of BF was associated with the type of delivery (vaginal/Caesarean section) and hospital-related factors (rooming-in, night feedings and frequency of mother–infant interaction). Of the mothers who breast-fed exclusively beyond 6 months, 86.7% had initiated BF a few hours following delivery, while only 13.3% had initiated BF a few days later. Compared with the exceptionally high proportion of BF initiation, exclusivity of BF was low, dropping to 52.4% at 1 month. Exclusivity of BF was also associated with place of residence (urban/rural) and negatively associated with educational level of the mother. Duration of BF was inversely associated with the use of pain killers during delivery and maternal education. Rural mothers and those who practised exclusive BF maintained BF for a longer duration.

Initiation rates of BF are very high in Lebanon but rates of exclusive BF are low and duration of BF is short. Future research targeting the factors associated with BF, with particular emphasis on exclusivity, is needed. For the 95.4% of mothers who initiated BF, an ecological perspective on intervention aimed at women and their social support system is required to improve duration and exclusivity.

To assess predictors of poor anthropometric status among infants and young children.

Cross-sectional survey.

The rural subsistence agricultural district of Hoima, western Uganda.

Seven hundred and twenty children aged 0–23 months with their mothers/carers.

Participants were recruited in September 2002, using a two-stage cluster sampling methodology. A structured questionnaire was administered to mothers in their home settings. Information on health, household socio-economic status, child feeding practices and anthropometric measurement was gathered. Conditional logistic regression analysis was applied taking into account the hierarchical relationships between potential determinants of poor anthropometric status.

The mean Z-score for weight-for-height was −0.2 (95% confidence interval (CI) −0.1, −0.7), for height-for-age was −1.1 (95% CI −1.2, −0.9) and for weight-for-age was −0.7 (95% CI −0.8, −0.6). Wasting was independently associated only with a history of fever in the 2 weeks prior to the survey (odds ratio (OR) = 4.4, 95% CI 1.5, 13), while underweight was associated with a history of fever (OR = 2.4, 95% CI 1.3, 4.4) and cough (OR = 3.0, 95% CI 1.3, 6.8). Stunting was positively associated with a wider range of factors, including: history of a fever episode (OR = 1.7, 95% CI 1.0, 2.9), lack of a latrine in the household (OR = 2.7, 95% CI 1.5, 4.9), failure to de-worm children 12 months or older (OR = 1.7, 95% CI 1.1, 2.8), and being born to a non-formally educated mother compared with mothers educated above primary school (OR = 2.1, 95% CI 1.1, 4.0).

In analyses guided by the hierarchical interrelationships of potential determinants of malnutrition, wasting and underweight turned out to be independently predicted by morbidity (proximal) factors. Stunting, however, was predicted by socio-economic (distal), environmental and health-care (intermediate) factors in addition to morbidity. Strategies aimed at improving the growth of infants and young children in rural communities should address morbidity due to common childhood illness coupled with environmental and socio-economically oriented measures.

To report the nutritional status of children aged up to 15 years and their mothers living in a remote Amazonian area of Bolivia, and to study its main social, familial and maternal determinants.

Fifteen Beni River communities located at the foot of the Andes.

Cross-sectional survey of riverside populations. All childbearing mothers and their children in the 15 communities were examined.

Information on household production, dietary habits and demography was collected. Individual clinical, anthropometric and parasitological examinations were carried out.

A total of 631 persons were examined: 171 mothers and 460 children and adolescents aged 0 to 15 years.

There were no cases of severe wasting, but 41% of 0–5-year-olds and 36% of 5–10-year-olds were stunted. Among 346 stool specimens examined, 75% were positive for at least one helminth. Diversity of food and quality of diet were satisfactory in 54% of households, but 27% had low diversity scores. Mothers were lighter and shorter than those observed at the national level: 20% had height below 145 cm. Prevalence of anaemia (42%) was also higher. In pre-school children, multivariate analysis indicated a relationship between growth retardation and household factors such as dietary quality, ethnic group and clinical state, but not maternal anthropometry. In contrast, in school-age children and adolescents, growth retardation was related to maternal characteristics.

Growth retardation appeared mainly during the weaning period and did not seem to improve thereafter. To ameliorate this situation, an effort should be made to prevent common parasitic and infectious diseases in young children. Follow-up of pregnant mothers during pregnancy and delivery also needs to be reinforced.

To examine consumption rates and serum ferritin (SF) concentrations (as a marker of safety) among schoolchildren (3–6 years) provided with daily and weekly micronutrients.

Micronutrients were provided for one school term (13 weeks) to a kindergarten in northern China as single-dose SprinklesTM sachets containing 30 mg of iron as encapsulated ferrous fumarate, 5 mg zinc gluconate, 50 mg vitamin C, 300 μg vitamin A, 7.5 μg vitamin D3 and 150 μg folic acid. Sixteen classrooms were randomly assigned to: (1) daily supplements for 5 days a week (daily group); (2) weekly supplements (weekly group); or (3) no supplements (control group). Consumption of sachets was monitored for each child and SF concentrations were measured at the end of study. Random effects general linear models and graphs were used to compare the groups.

A total of 415 children from 16 classrooms entered the study. At the end of the study, mean consumption rates per child were 86% (daily group; standard deviation (SD) 12%) and 87% (weekly group; SD 16%). Median SF concentrations were 71 μg l−1 (range 27–292 μg l−1; daily group), 55 μg l−1 (range 11–299 μg l−1; weekly group) and 54 μg l−1 (range 7–327 μg l−1; control group); the overall difference was not significant (P = 0.06). However, the daily group was significantly different from the control (P = 0.02); daily and weekly groups had higher SF at lower percentiles and similar SF at higher percentiles compared with the control group.

The high consumption rates and appropriate SF concentrations in the supplemented groups suggest that a short-term school programme with Sprinkles is an efficient and safe way to provide micronutrients (including iron).

To investigate the prevalence of anaemia and subclinical vitamin A deficiency among adolescent schoolboys in Dhaka City, Bangladesh, and to identify factors related to anaemia and vitamin A status.

A cross-sectional study.

Government high schools in Dhaka City, Bangladesh.

A total of 381 boys, aged 11–16 years, from 10 schools in Dhaka City participated in the study. Socio-economic, anthropometric and dietary data were collected. Haemoglobin and serum retinol (vitamin A) concentrations were determined.

Seven per cent of the boys were anaemic and 22% had serum vitamin A levels below the adequate level of 1.05 μmol l−1, with only 1.5% having subclinical vitamin A deficiency (<0.70 μmol l−1). Food frequency data revealed poor dietary habits. Multiple regression analysis showed that age, body mass index (BMI), parents' occupation, serum vitamin A level and frequency of intakes of meat and fruit were significantly independently related to haemoglobin level. The overall F-ratio (13.1) was highly significant (P< 0.000) and the adjusted R2 was 0.192. For serum vitamin A, BMI, father's education, per capita expenditure on food, haemoglobin concentration and frequency of intake of vitamin A-rich fruit were found to be significantly independently related. The overall F-ratio (14.5) was highly significant (P< 0.000) and the adjusted R2 was 0.186.

The data show that adolescent schoolboys in Dhaka City have anaemia and inadequate vitamin A status, although the extent of the problems is lower than in other population groups in the country. Sociodemographic and dietary factors appear to have important relationships with anaemia and vitamin A status of these boys.

To investigate the determinants of overweight and obesity among 10- to 15-year-old schoolchildren in a population in the transitional phase in the North West Province of South Africa.

A cross-sectional survey was used to investigate weight status (anthropometric indicators) and determinants of overweight/obesity including dietary intake, physical activity and socio-economic status. A single, random sample (n=1257), stratified for gender, type of school and ethnic group, was used. Data were collected on demographics, family circumstances, habitual physical activity, dietary intake and anthropometry to evaluate weight status and body fat content. One-way analysis of variance, the generalised linear models procedure of SAS and the Tukey post hoc honest significant difference test were used to analyse the data.

Few children were overweight or obese (7.8%) according to International Obesity Task Force (IOTF) standards (body mass index (BMI)-for-age). These standards were compared with other accepted standard values. Both Cole's IOTF/BMI-for-age standard and the sum of skinfold thicknesses standard classified normal-weight status similarly at a level of 92% (P<0.01) and were found to be useful in determining overweight/obesity. The prevalence rate was higher in females and white children, and was more apparent in urban areas, smaller households and children of parents with low- or high-income occupations. Boys and pre-menarcheal girls had mean body fat percentage in the normal/optimal range, whereas that of post-menarcheal girls was moderately high. Few variables showed a significant association with high body fat percentage: in boys, only the number of members in the household and physical activity levels over the weekend; in girls, only age. The overweight/obese boys mostly lived in smaller households, and the overweight/obese post-menarcheal girls were most inactive on both weekdays and weekends, and more overweight with increasing age.

Smaller households, inactivity and increasing age for girls were found to be determinants that influence the development of overweight/obesity, while female gender and age post-menarche were identified as determinants of higher body fat content. For overweight/obesity prevention, the focus should be on pre-menarcheal girls, aged 10–13 years, using these determinants to identify overweight/obesity risk. Preventive programmes should aim to increase the physical activity of children to improve their current and future weight status.

The mechanisms underlying the association of insulin-like growth factor-I (IGF-I) and leg length (a marker of prepubertal growth) with cancer risk are uncertain. One hypothesis is that diet in early childhood might provide the link. The aim of the present study was to examine the association between early diet – in particular, the intakes of cows' milk and dairy products – and height, leg length and IGF-I levels at age 7–8 years.

Children participating in the Avon Longitudinal Study of Parents and Children.

Diet was assessed using a 3-day unweighed food record. Anthropometry, IGF-I and insulin-like growth factor-binding protein-3 (IGFBP-3) were measured by standard methods.

Data on both diet and height were available for 744 children (404 boys) and on diet and IGF for 538 (295 boys). After adjusting for energy, both cows' milk and dairy product intakes were positively associated with IGF-I (P=0.040 and 0.027, respectively) and IGFBP-3 levels (P=0.082 and 0.067, respectively). These associations persisted on adjustment for potential confounders, but were abolished on controlling for protein intake. In energy-adjusted models there was only weak evidence of associations of milk and dairy product intakes with anthropometry. In boys only, dairy product intake was positively associated with leg length (equivalent to a 0.058 (0.002, 0.114) standard deviation score increase in leg length per 100 g increase in daily intake).

These data provide some evidence that variation in childhood milk and dairy product intakes underlies associations of leg length, IGF-I and cancer risk. The association appears to be due to the protein content of milk.

As intake of flavonoids has been associated with reduced risk of coronary heart disease but data on the relation with specific classes of flavonoids are scarce, we assessed the relation between dietary intake of specific classes of flavonoids and the risk of acute myocardial infarction (AMI) in an Italian population.

Case–control study. Dietary information was collected by interviewers on a questionnaire tested for validity and reproducibility. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were obtained by multiple logistic regression models including terms for energy and alcohol intake, as well as sociodemographic factors, tobacco and other major recognised risk factors for AMI.

Milan, Italy, between 1995 and 2003.

Cases were 760 patients, below age 79 years, with a first episode of non-fatal AMI, and controls were 682 patients admitted to hospital for acute conditions unrelated to diet.

A reduced risk of AMI was found for increasing intake of anthocyanidins (OR = 0.45, 95% CI 0.26–0.78 for the highest vs. the lowest quintile, Ptrend = 0.003) and flavonols (OR = 0.65, 95% CI 0.41–1.02, Ptrend = 0.02). A tendency towards reduced risks, although not significant, was observed for flavan-3-ols (OR = 0.73, 95% CI 0.48–1.10) and total flavonoids (OR = 0.74, 95% CI 0.49–1.14). No meaningful heterogeneity was found between the sexes. No association emerged for other flavonoids, including isoflavones, flavanones and flavones.

High intake of anthocyanidins reduced the risk of AMI even after allowance for alcohol, fruit and vegetables, supporting a real inverse association between this class of flavonoids and AMI risk.

To examine the association between education level and food purchasing behaviour and the contribution of dietary knowledge to this relationship; and the association between household income and purchasing behaviour and the contribution made by subjective perceptions about the cost of healthy food.

The study was conducted in Brisbane City (Australia) in 2000. The sample was selected using a stratified two-stage cluster design. Data were collected by face-to-face interview from residents of private dwellings (n = 1003), and the response rate was 66.4%. Dietary knowledge was measured using a 20-item index that assessed general knowledge about food, nutrition, health and their interrelationships. Food-cost concern was measured using a three-item scale derived from principal components analysis (α = 0.647). Food purchasing was measured using a 16-item index that reflected a household's purchase of grocery items that were consistent (or otherwise) with dietary guideline recommendations. Associations among the variables were analysed using linear regression with adjustment for age and sex.

Significant associations were found between education, household income and food purchasing behaviour. Food shoppers with low levels of education, and those residing in low-income households, were least likely to purchase foods that were comparatively high in fibre and low in fat, salt and sugar. Socio-economic differences in dietary knowledge represented part of the pathway through which educational attainment exerts an influence on diet; and food purchasing differences by household income were related to diet in part via food-cost concern.

Our findings suggest that socio-economic differences in food purchasing behaviour may contribute to the relationship between socio-economic position and food and nutrient intakes, and, by extension, to socio-economic health inequalities for diet-related disease. Further, socio-economic differences in dietary knowledge and concerns about the cost of healthy food play an important role in these relationships and hence should form the focus of future health promotion efforts directed at reducing health inequalities and encouraging the general population to improve their diets.

To identify the most common frequency of food-purchasing patterns and relate this pattern to characteristics of individuals and families.

A customer-intercept survey was conducted in the greater Houston area, Texas, USA, in 2002. The frequency of food shopping at supermarkets, convenience stores and restaurants to buy food for eating at home was assessed.

A total of 823 adults (78.5% female; mean age 37.4 years) who went to any of several grocery or convenience stores, including European, Hispanic and African Americans, and Asian/Pacific Islanders.

Major food-shopping patterns were a weekly big trip with a few small trips (34.9%), biweekly big trips with a few small trips (21.9%), no big shopping trips (15.4%), a weekly big trip without small trips (13.9%), a monthly big trip (8.3%), and biweekly big trips without small trips (6.4%). While 61.1% of participants never went to convenience stores to buy fruit and vegetables (F&V) for eating at home, 67% went to restaurants for F&V. African American families shopped for food least frequently, while Asian American families shopped for food most frequently. Educational level was negatively associated with the use of convenience stores and positively associated with takeaway from restaurants.

There is substantial variability in the frequency of food shopping. Future research on food shopping should incorporate this variable.

To assess validity of the Nambour food-frequency questionnaire (FFQ) relative to weighed food records (WFRs), and the extent to which selected demographic, anthropometric and social characteristics explain differences between the two dietary methods.

Inter-method validity study; 129-item FFQ vs. 12 days of WFR over 12 months.

Community-based Nambour Skin Cancer Prevention Trial.

One hundred and fifteen of 168 randomly selected participants in the trial (68% acceptance rate) aged 25–75 years.

Spearman correlations between intakes from the two methods ranged from 0.18 to 0.71 for energy-adjusted values. Differences between FFQ and WFR regressed on personal characteristics were significantly associated with at least one characteristic for 16 of the 21 nutrients. Sex was significantly associated with differences for nine nutrients; body mass index (BMI), presence of any medical condition and age were each significantly associated with differences for three to six nutrients; use of dietary supplements and occupation were associated with differences for one nutrient each. There was no consistency in the direction of the significant associations. Regression models explained from 7% (riboflavin) to 27% (saturated fat) of variation in differences in intakes.

The relative validity of FFQ estimates for many nutrients is quite different for males than for females. Age, BMI, medical condition and level of intake were also associated with relative validity for some nutrients, resulting in the need to adjust intakes estimates for these in modelling diet-disease relationships. Estimates for cholesterol, β-carotene equivalents, retinol equivalents, thiamine, riboflavin and calcium would not benefit from this.