To examine the effects of socioeconomic status and biocultural variables (planned pregnancy, prenatal care, timing of initiation of breast-feeding and caesarean section delivery) on breast-feeding duration in Peru using structural equation models.

Structural equation models were analysed with LISREL using data from the 1991–92 Peruvian Demographic and Health Survey.

Models were tested among 6020 women whose last child was born within 5 years of the survey and among 2711 women whose last child was born 2–5 years preceding the survey.

Unplanned pregnancy and socioeconomic status had a negative influence on breast-feeding duration. Prenatal care was positively associated with the timing of breast-feeding initiation in both samples and with breast-feeding duration in the whole sample. The timing of breast-feeding initiation was inversely associated with breast-feeding duration only in the sample of older children.

These results imply that an unplanned pregnancy, a delayed breast-feeding initiation, and higher socioeconomic status are risk factors for an earlier discontinuation of breast-feeding through complex mechanisms involving direct and indirect effects.

To explore British African-Caribbean (AfC) nutrient intake by migration status (place of birth), diet (traditional Caribbean or more European) and age and relate this ecologically to coronary heart disease (CHD) mortality rates.

Cross-sectional.

Inner-city Manchester, UK.

Two hundred and fifty-five adults of AfC origin aged 25–79 years, randomly sampled from population registers.

Caribbean-born people (mean age 56, and mean time in Britain 30 years) had significantly lower per cent energy from total and saturated fat than younger British-born AfC people (mean age 29 years) (31.3% vs. 35%, difference in total fat 3.7%, 95%CI 2–5%; in saturated fat 10.9% vs. 12.6%, difference 1.7%, 95%CI 1–2.5%). The Caribbean-born group also ate more fruit (+84 g day−1, 95%CI 36–132 g day−1) and green vegetables (+26 g day−1, 95%CI 3–49 g day−1). Men following a traditional diet (>= 5 days week−1) similarly had a lower per cent energy from fat, at 30.4%, than less traditional eaters, at 33.1% (difference 2.7%, 95%CI 0.7–4.8%). African-Caribbean women, at relatively greater CHD risk than AfC men, had higher body mass indices (BMIs) than AfC men. Compared with national data, AfC subjects consumed some 7% and 5% less energy from total fat and saturated fat, respectively, with over 9% more from carbohydrate. However, there was marked convergence towards the national average in the youngest AfC groups aged 25–34 years, whatever their place of birth.

Caribbean birthplace has an independent effect on total fat intake and percentage of energy from fat. Together with higher fruit and vegetable intake, these results are consistent with the dietary fat/antioxidant/CHD hypothesis.

To determine whether responses to simple dietary questions are associated with specific causes of death.

Self-reported frequency intakes of various classes of foods and data on confounding factors were collected at the baseline survey. Death notifications up to 31 December 1997 were ascertained from the Office for National Statistics. Relative risk (RR) of death and 95% confidence intervals (CI) associated with baseline dietary factors were calculated by Cox regression.

Prospective follow-up study based on five UK general practices.

Data were used from 11 090 men and women aged 35–64 years (81% of the eligible patient population) who responded to a postal questionnaire in 1989.

After 9 years of follow-up, 598 deaths were recorded, 514 of these among the 10 522 subjects with no previous history of angina. All-cause mortality was positively associated with age, smoking and low social class, as expected. Among the dietary variables, all-cause mortality was significantly reduced in participants who reported relatively high consumption of vegetables, puddings, cakes, biscuits and sweets, fresh or frozen red meat (but not processed meat), among those who reported using polyunsaturated spreads and among moderate alcohol drinkers. These associations were broadly similar for deaths from ischaemic heart disease (IHD), cancer and all other causes combined, and were not greatly attenuated by adjusting for potential confounding factors including social class.

Responses to simple questions about nutrition were associated with mortality. These findings must be interpreted with caution since residual confounding by dietary and lifestyle factors may underlie the associations.

To review the current literature on the effects of soy isoflavones, one class of phyto-oestrogens, on cardiovascular diseases, osteoporosis, cancer and climacteric symptoms.

Many study designs were employed in the reports reviewed here, including prospective human trials, observational human studies, animal experiments and in vitro cell studies that explored the protective or preventive effects of soy isoflavones (genistein, daidzein and glycitein alone or mixed).

Diverse settings were employed, depending on study design.

Human subjects, mostly menopausal or postmenopausal, were included, as were animal models and specific cell types.

The findings were: (i) isoflavones plus soy protein together were needed to obtain the highly significant beneficial results on blood lipids and arterial dimensions; (ii) isoflavone treatments alone at high doses (relative to above) consistently improved bone parameters in rodent ovariectomized models, but not in humans or primates; (iii) isoflavones were not consistent in exerting positive effects regarding the prevention or treatment of cancers of the mammary glands, uterus and colon; and (iv) the effects of isoflavones on climacteric symptoms were not clear-cut.

The promise of soy isoflavones reducing chronic disease risk seems to be non-uniform, with the most conclusive benefits occurring in the prevention of cardiovascular diseases, but other organ systems, such as skeletal and reproductive tissues, may also benefit from the consumption of soy and soy-derived products.

To investigate the direct and indirect cost differences associated with eating a ‘healthy’ or ‘unhealthy’ diet.

Analysis of data from a baseline postal questionnaire for the UK Women's Cohort Study, including a detailed food frequency questionnaire (FFQ), supplemented by a telephone interview on a sub-sample.

The first 15 191 women who responded to the questionnaire, aged 35–69 years with similar numbers of meat eaters, fish eaters and vegetarians.

A healthy diet indicator (hdi), with values from 0 (lowest) to 8 (highest) was developed based on the WHO dietary recommendations. Direct monetary cost of the diet was calculated using prices from the 1995 National Food Survey and the Tesco home shopping catalogue. Women in the healthy diet group were almost four times as likely to be vegetarian and have a higher educational level. For direct costs, the difference between the most extreme hdi groups was £1.48 day−1 (equivalent to £540 year−1), with fruit and vegetable expenditure being the main items making a healthy diet more expensive. Forty-nine per cent of the food budget was spent on fruit and vegetables in hdi group 8 compared to 29% in hdi group 0. Interestingly, 52% of those questioned in both extreme hdi groups did not think that it was difficult to eat healthily.

To achieve a particularly healthy diet independent predictive factors were spending more money, being a vegetarian, having a higher energy intake, having a lower body mass index (BMI) and being older.

To investigate links between taste responses, self-reported food preferences and selected dietary outcomes in young women.

Subjects were 159 women, with a mean age of 27.0 years. Taste responses were measured using aqueous solutions of 6−n-propylthiouracil (PROP) and sucrose. All subjects completed a 171-item food preference checklist, using nine-point category scales. Food preference data were reduced using principal components factor analyses, with the internal consistency of factor-based subscales established using Cronbach's alpha. Dietary intakes, available for a subset of 87 women, were based on 3 days of food records. Estimated intakes of carbohydrate, fibre and β-carotene were the key dietary outcome variables.

Genetically-mediated sensitivity to the bitter taste of PROP was associated with reduced preferences for Brussels sprouts, cabbage, spinach and coffee beverages. Higher preferences for sucrose in water were associated with increased preferences for sweet desserts. Food preferences, in turn, were associated with measures of current diet. Reduced acceptability of vegetables and fruits was associated with lower estimated intakes of carbohydrate, fibre and β-carotene.

Taste responses to sucrose and PROP were predictive of some food preferences. Food preferences, in turn, were associated with food consumption patterns. Given that taste responsiveness to PROP is an inherited trait, there may be further links between genetic taste markers, eating habits and the selection of healthful diets.

To examine associations between breakfast cereal consumption and iron status and identify dietary patterns that might improve iron status in this vulnerable group.

Analysis of data from the UK National Diet and Nutrition Survey (NDNS) of children aged 1.5–4.5 years, including dietary intakes calculated from 4-day weighed records.

Data were used from 904 children with haematological measurements, excluding those taking iron supplements; 20% had low iron stores (ferritin < 10 μg l−1) while 8% were anaemic (Hb < 11 g dl−1).

High cereal consumers had significantly higher iron intakes than low cereal consumers (classified by tertiles) but the 10% difference in mean ferritin levels was not significant (P = 0.067). Lower intakes of vitamin C and meat among high consumers of cereal may have diluted the impact of cereal iron on iron status. When children were reclassified according to their intakes of vitamin C and iron from meat and breakfast cereals, the group with high (above median) intakes of two or more factors had a higher mean haemoglobin (Hb) level and a lower prevalence of anaemia compared with the group with low (below median) intakes of all three dietary constituents.

Nutritional advice that aims to improve iron status should emphasize not only rich sources of iron but also factors that may enhance or inhibit absorption. Strategies to optimize iron status in this vulnerable age group include consuming an iron-fortified breakfast cereal, vitamin C-rich fruit or drink at breakfast, and avoiding tea with (or after) meals.

To compare vitamin B6 status indices with each other and with potential confounding factors, in the datasets from two national British surveys and associated studies.

Vitamin B6 status was measured by plasma pyridoxal phosphate (PLP) and plasma pyridoxic acid (PA) in both surveys, and also by erythrocyte aspartate aminotransferase activation coefficient (EAATAC) in one of the surveys. Plasma α1-antichymotrypsin was measured as an index of acute phase status; plasma creatinine was measured as an index of renal function; and plasma total alkaline phosphatase activity was measured as a proxy for PLP hydrolase activity.

The survey of people aged 65 years and over was carried out in 80 postcode sectors across mainland Britain during 1994–95 and the survey of young people was carried out in 132 postcode sectors across mainland Britain during 1997.

Blood samples from c. 1000 subjects of both sexes in each survey permitted measurements of plasma PLP and PA. There were also measurements of EAATAC in the young people's survey.

According to published limits of normality, only 5% or less of the young people had unacceptable vitamin B6 status as measured by plasma PLP. About half had apparently unacceptable status by EAATAC, but this observation is difficult to interpret. The young people had considerably higher plasma concentrations of PLP and lower concentrations of PA than the older people. In both surveys, plasma PLP was strongly correlated with plasma PA and in the young persons’ survey it was also correlated, although much less strongly, with the basal activity and activation coefficient of aspartate aminotransferase. Both plasma PLP and EAATAC (but not PA nor basal aspartate aminotransferase activity) were influenced by acute phase status in young people, as indicated by significant correlations with α1-antichymotrypsin. In people aged 65 years and over, PA (but not PLP) was correlated with renal function, as indicated by its relation with plasma creatinine; however PLP (but not PA) was correlated with plasma alkaline phosphatase activity.

Several potential confounders — acute phase reaction, kidney malfunction and hydrolase activity — may influence vitamin B6 status indices, although differently for different indices and different age groups. Since older people have relatively poor vitamin B6 status, which may have important health implications for them, more reliable vitamin B6 status indices are needed.

To evaluate the food and nutrient intake of members of a birth cohort study when young children in 1950 and investigate differences from present-day children's diets.

One-day recall diet records from the MRC National Survey of Health and Development (NSHD) (1946 Birth Cohort) at age 4 years were analysed for energy and selected nutrients and compared to the published results for 4-year-olds in the 1992/93 National Diet and Nutrition Survey (NDNS).

England, Scotland and Wales in 1950 and 1992/93.

4599 children in 1950 and 493 children in 1992/93.

Mean (SD) daily intakes in 1950 were energy 1445 (343) kcal, or 6.1 (1.4) MJ, protein 46 (11)g, fat 64 (20)g, starch 117 (33)g, sugar 62 (24)g, unavailable carbohydrate 13 (4)g, calcium 736 (230)mg, iron 7.7 (2.1)mg, retinol 738 (1273) μg, carotene 1049 (1130) μg and vitamin C 40 (26) mg. Compared to 1992/93, the 1950 diet contained substantially more bread and vegetables and less sugar and soft drinks, giving it a higher starch and fibre content and making it more in line with current recommendations on healthy eating. However, fat provided 40% of energy in 1950, compared to 35% in 1992/93. In 1950, red meat was an important source of iron, but by 1992 most iron came from fortified breakfast cereals. Vitamin C came mainly from vegetables in 1950, but from soft drinks in 1992.

The relative austerity of post-war food supplies resulted in food and nutrient intakes in 1950 which in many respects may well have been beneficial to the health of young children, despite fat intake being higher than present-day recommendations.

To assess the impact and suitability of a pilot dietary educational programme for primary school pupils. The Nutrition Education at Primary School (NEAPS) programme aimed to build awareness of the benefits of healthy eating, induce positive behaviour change and increase the children's knowledge.

A comparative quasi-experimental study with follow-up after 3 months.

Eight primary schools in the Eastern and North Western Health Boards and three control schools in the same board regions.

Data were used from 821 Irish school children aged 8–10 years old.

The education programme comprised 20 sessions over 10 weeks including circular worksheets, homework assignments and an aerobic exercise regime. At baseline and after 3 months pupils completed food diaries and a validated food pairing questionnaire on food behaviour, knowledge and preferences.

Significant differences were found in the intervention children's behaviour and preference levels after the NEAPS programme (P < 0.01 in both sections). Knowledge levels were very high at baseline and though some individual items improved, average change overall was not significant. Rural children appeared to benefit more in behaviour and preferences from the programme (P < 0.01). The NEAPS programme appeared to be less effective in pupils in disadvantaged areas (P < 0.01 for each of the sections: behaviour, preference and knowledge). One hundred and eighty-seven children completed food diaries. The intervention children's consumption of fruit and vegetables increased, and they consumed less salty snacks after the programme. Rural children were confirmed to have healthier diets at baseline.

Following the NEAPS pilot programme positive changes were seen in the school children's eating behaviour and preferences for healthier foodstuffs. This suggests successful development of a culturally sensitive nutrition education programme for school children aged 8–10 years.

To assess the more prevalent beliefs about body weight and the factors involved in weight changes in the Spanish adult population.

A national survey was carried out according to an established protocol on Spanish subjects selected by a multistage procedure following a random route model, which was quota-controlled for several sociodemographic variables. This study was undertaken by the Spanish arm of a pan-European survey and was performed with a validated questionnaire. It contained questions to evaluate some aspects concerning the relationship between obesity, physical activity and health. We also estimated the proportion of self-reported overweight and obesity.

Spain.

The sample included 1000 subjects aged 15 years or older.

Eleven per cent of the sample were obese (body mass index, BMI > 30 kg m-2) and an additional 32% were overweight (BMI > 25 and < 30 kg m-2). Obesity prevalence was higher among older individuals, those with lower education and socioeconomic levels, and among housewives and retired or unemployed people. Most Spanish people believed that fat intake (51%) and the amount of food consumption (44%) were the major factors involved in weight gain, while physical activity was less mentioned (12%). The method most frequently used to lose weight was diet (9%). Individuals from central and southern regions payed more attention to genetics (20–27%) and physical activity (12–20%) as determinants of weight gain than people living in the north or northwest regions (15–17% and 8–9%, respectively). Normal weight people participated more often in some physical activity during their leisure time.

The Spanish population is not familiar with factors influencing weight gain. Health promotion strategies should emphasize the role of physical activity, especially among older individuals, retired or unemployed subjects, those from lower educational or socioeconomic levels and among people living in the north or northwest of Spain.

This study sought to evaluate the benefit of utilizing a nutritionist review of a self-administered food frequency questionnaire (FFQ), to determine whether accuracy could be improved beyond that produced by the self-administered questionnaire alone.

Participants randomized into a dietary intervention trial completed both a FFQ and a 4-day food record (FR) at baseline before entry into the intervention. The FFQ was self-administered, photocopied and then reviewed by a nutritionist who used additional probes to help complete the questionnaire. Both the versions – before nutritionist review and after nutritionist review – were individually compared on specific nutrients to the FR by means, correlations and per cent agreement into quintiles.

Three hundred and twenty-four people, a subset of participants from the Polyp Prevention Trial – a randomized controlled trial examining the effect of a low-fat, high-fibre, high fruit and vegetable dietary pattern on the recurrence of adenomatous polyps – were recruited from clinical centres at the University of Utah, University of Buffalo, Memorial Sloan Kettering Cancer Center in New York and Kaiser Permanente Medical Program in Oakland.

Reviewing the FFQ increased correlations with the FR for every nutrient, and per cent agreement into quintiles for all nutrients except calcium. Energy was underestimated in both versions of the FFQ but to a lesser degree in the version with review.

One must further evaluate whether the increases seen with nutritionist review of the FFQ will enhance our ability to predict diet–disease relationships and whether it is cost-effective when participant burden and money spent utilizing trained personnel are considered.

To assess the ability of a food frequency questionnaire (FFQ1) and a food checklist (FCL) to determine energy and macronutrient intakes of adolescent girls in the general population.

Energy and macronutrient intakes determined by FFQ1 and the FCL were compared with those from a 7-day weighed dietary record (WDR). The reproducibility of FFQ1 was assessed by a comparison of intakes with those from a repeated questionnaire (FFQ2) completed a month later.

Southampton, UK.

Forty-seven 15-year-old girls completed FFQ1 and the WDR and FCL; and 61 girls completed FFQ1 and FFQ2.

The broad dietary patterns described by the three methods of assessment were similar, although absolute intakes differed. Energy and macronutrient intakes determined by FFQ1 were higher than those recorded in the WDR (all P < 0.001), but intakes assessed by the FCL and WDR were similar. Only FFQ1-assessed energy intakes appeared consistent with predicted energy requirements. With the exception of protein intake, there was reasonable agreement between FFQ1 and the WDR in their estimation of energy and macronutrient intake (range of correlation coefficients 0.28 for energy to 0.33 for carbohydrate). The poorer agreement between FFQ1 and the WDR in their estimates of protein intake arose principally from the misclassification of meat and fish intake, although there was no obvious explanation for this. Energy and macronutrient intakes were similar for FFQ1 and FFQ2.

Adolescent girls give reproducible answers in response to a self-administered FFQ, which yield useful information about their broad dietary patterns. The FFQ may be a more suitable dietary assessment method than prospective records for use in general population studies of girls of this age. We discuss suggestions for its improved performance.

A novel system for nutrient analysis has been developed and tested over 5 years. Its key features are a nutrient database of 600 commonly eaten foods (95% of foods eaten in 7-day surveys); a booklet identifying each food with a bar code, bar codes for gram weight and for portion sizes (small, medium, large) and a bar-code reader with dietary analysis software for PCs. In the present study the bar-code system has been evaluated by comparison with a commonly used manual entry nutrient analysis software for dietitians' use.

Cross-sectional.

Glasgow city district.

One hundred and sixty adults aged 18–65 years old.

Comparing mean intakes for macro- and micronutrients, using the Bland and Altman method1, the bias between the two methods was small, ranging from 0.93 to 1.03. The bar-code system took significantly less professional time in data entry and nutrient analysis than the widely used manual system (29 min per 7-day diary vs. 47 min per 7-day diary, P < 0.001).

It is suggested that the bar-code system offers greater speed with a saving of professional time needed for nutrient analysis of dietary surveys. This system is commended for maintaining accuracy while promoting economy.

To develop a method to make use of incomplete 24-hour urinary samples in nutritional epidemiology, especially when validating the dietary intake of nitrogen (protein), sodium and potassium.

Urinary data for men and women collected in three different studies were evaluated. The concentration of para-aminobenzoic acid (PABA) in one 24-hour urine sample per person was compared with the concentrations of nitrogen, sodium, potassium and creatinine.

Men and women living in Cambridge, UK and women living in the town of Varberg, Sweden.

In total, this study consists of data from 73 Swedish women (20–50 years of age), 165 UK women (50–65 years) and 75 UK men (55–88 years).

On average four out of 10 people in this study had a PABA recovery below 85%. The linear regression equations for urinary excretion of nitrogen, sodium and potassium in relation to PABA recovery were y = 2.3 + 0.088 * x (r = 0.99), y = 45 + 0.82 * x (r = 0.87) and y = 19 + 0.60 * x (r = 0.93), respectively.

The linear regression equations can be used for adjusting urinary nitrogen, sodium and potassium in urinary collections in cases where the PABA recovery is below 85%. Since it is common to obtain 24-hour urine collections with a PABA recovery below 85%, this method should increase the usefulness of biological markers of food intake in nutritional epidemiological studies and also increase the possibilities to study people that previously have been part of the drop-out group or the group with low motivation and cooperation. It is important to stress that we have not studied the relationship between PABA recovery and various urinary variables below the PABA recovery of 50%. Thus, in a case of PABA recovery below 50%, we do not recommend the use of this method to compensate for incomplete collections.