To review the evidence on the diet and nutrition causes of obesity and to recommend strategies to reduce obesity prevalence.

The evidence for potential aetiological factors and strategies to reduce obesity prevalence was reviewed, and recommendations for public health action, population nutrition goals and further research were made.

Protective factors against obesity were considered to be: regular physical activity (convincing); a high intake of dietary non-starch polysaccharides (NSP)/fibre (convincing); supportive home and school environments for children (probable); and breastfeeding (probable). Risk factors for obesity were considered to be sedentary lifestyles (convincing); a high intake of energy-dense, micronutrient-poor foods (convincing); heavy marketing of energy-dense foods and fast food outlets (probable); sugar-sweetened soft drinks and fruit juices (probable); adverse social and economic conditions—developed countries, especially in women (probable).

A broad range of strategies were recommended to reduce obesity prevalence including: influencing the food supply to make healthy choices easier; reducing the marketing of energy dense foods and beverages to children; influencing urban environments and transport systems to promote physical activity; developing community-wide programmes in multiple settings; increased communications about healthy eating and physical activity; and improved health services to promote breastfeeding and manage currently overweight or obese people.

The increasing prevalence of obesity is a major health threat in both low- and high income countries. Comprehensive programmes will be needed to turn the epidemic around.

To identify correlates of 6th and 7th graders' (age 10–12 years) fruit and vegetable intake, to investigate parent–child correlations of fruit and vegetable intake, and to compare parents' and children's reports of children's accessibility, skills and preferences with respect to fruit and vegetables.

The results presented are based on the baseline survey of the ‘Fruits and Vegetables Make the Marks Project’, where 38 schools participated.

Fruit and vegetable intake was measured by food frequency questions. Theoretical factors, based on Social Cognitive Theory, potentially correlated to intake were measured, including behavioural skills, accessibility, modelling, intention, preferences, self-efficacy and awareness of 5-a-day recommendations.

In total, 1950 (participation rate 85%) 6th and 7th graders and 1647 of their parents participated.

Overall, 34% of the variance in the pupils' reported fruit and vegetable intake was explained by the measured factors. The strongest correlates to fruit and vegetable intake were preferences and accessibility. The correlation between the children's and their parents' fruit and vegetable intake was 0.23. The parents perceived their children's accessibility to be better than what was reported by the children (P<0.01), while the children reported their skills to be better than what was perceived by their parents (P<0.01).

The results from this study clearly point to a need for nutrition interventions aimed at parents. An important next step will be to investigate whether the identified correlates predict future fruit and vegetable intake, and whether they mediate any changes in intake in an intervention study.

To assess whether the amount of fruits and vegetables consumed depends on the serving size or on how often fruits and vegetables are eaten.

Estimation of the weight of serving sizes and the number of fruits and vegetables eaten daily, using a validated food diary method.

Free-living men and women participating in the Norfolk arm of the European Prospective Investigation into Cancer and Nutrition (EPIC).

Two hundred and sixty-nine men and women sampled from EPIC–Norfolk to participate in a study of simple methods of assessing fruit and vegetable intakes.

The average portion of all fruits and vegetables measured was 87 g, close to the standard portion size of 80 g used as the basis of ‘5-a-day’ recommendations. There was a wide variation; the average portion size for baked beans was 147 g while for lettuce it was 26 g. The 20th and 80th percentiles also showed a large range, e.g. 39–72 g for carrots and 60–150 g for strawberries. Women ate more fruit than did men but fewer vegetables, so the total amount of fruit and vegetables eaten by men and women was the same. High consumers of fruits and vegetables (≥400 g day-1) ate them ~5 times a day whilst low consumers (<400 g day-1) ate them less often (~3 servings per day, P<0.01). Portion size differed little between high and low consumers.

Frequency of intake is more important than portion size when distinguishing between high and low consumption of fruits and vegetables. Therefore, to increase intakes, low consumers should eat fruits and vegetables more often. This endorses the ‘5-a-day’ healthy eating message.

Pregnancy and postpartum iron status is of great public health importance, yet few studies have examined predictors of haemoglobin (Hb) concentration during this time. We identified predictors of Hb from 24 weeks' gestation until delivery and from 4 to 25 weeks postpartum.

Blood was drawn as many as four times during care: at the initial visit, at 24–29 weeks' gestation, at delivery and postpartum. A longitudinal, multivariable linear regression model was used to predict Hb concentration.

A public health clinic in Raleigh, North Carolina.

n = 520 women who participated in the Iron Supplementation Study.

Hb concentration at the previous blood draw, short stature, non-Hispanic white ethnicity/race, > 12 years of education and smoking were positive predictors of pregnancy and postpartum Hb concentrations. Iron supplement use was a positive predictor, while inadequate weight gain and severe nausea/vomiting were negative predictors of gestational Hb. A high infant birth weight and postpartum haemorrhage were negative predictors of postpartum Hb. Pre-pregnancy body mass index had a slight positive relationship with gestational Hb, but had a strong negative relationship with postpartum Hb. The longitudinal model also confirmed the typical pattern of gestational Hb concentration. As the number of weeks between the initial visit and the 24- to 29-week visit increased, Hb at 24–29 weeks' gestation decreased. As gestational age increased from 24 weeks until delivery, Hb concentration increased as well.

The predictors identified here could be used in clinical settings to target high–risk women for intervention.

To stress the importance of social and environment (nutritional) factors in determining the growth spurt during puberty and the risk of excessive adiposity, two contrasting adolescent populations, one from a rural area of Senegal (West Africa) and the other from Martinique (French West Indies), were compared.

Cross-cultural comparison of contrasting populations. Adolescents from Senegal belonged to a cohort followed up since 1995. Adolescents from Martinique participated in a cross-sectional nutritional survey that covered the entire island.

A total of 507 adolescents (mean age: 14.3 ± 0.7 years) from Senegal (319 girls and 188 boys) and 703 adolescents from Martinique (351 boys and 352 girls) were surveyed.

Differences in growth and maturation were striking: boys in Martinique were 22.7 kg heavier and 20.1 cm taller than boys in Senegal. Differences were less important for girls but still evident: 12.6 kg in weight and 10.5 cm in stature. In Senegal, there were virtually no overweight adolescents, but 18% of girls and 50% of boys could be considered as malnourished. In Martinique, 19% of girls and 23% of boys were overweight or obese. Adolescent girls from Martinique were also sexually more mature than adolescent girls from Senegal. When comparisons were repeated after Senegalese girls reached menarche, differences in weight and body mass index disappeared, but Senegalese girls were still shorter than girls from Martinique.

Adolescents are extremely susceptible to nutritional changes and their particular situation needs to be incorporated into nutritional prevention programmes.

To compare trends in the consumption of key foods over 10 years in the most deprived and least deprived quarters in north Glasgow, Scotland as defined by the Carstairs deprivation index for their postcode of domicile.

Four random, cross-sectional, age- and gender-stratified population surveys carried out in 1986, 1989, 1992 and 1995. After assigning a deprivation score, food-frequency questionnaires from 2883 men and 3127 women were examined for compliance with dietary targets, examining trends by gender and within the most and least deprived quarters of the population.

North Glasgow, Scotland.

Over 600 men and 600 women (aged 25–64 years) in each of the four survey years who completed a lifestyle questionnaire including a food frequency section.

Increasing trends in the reported consumption of fruit and vegetables and oil-rich fish were observed over the 10-year period. However, the trend to increased fruit and vegetable consumption in the most deprived groups was not significant, and in 1995 only 8% of men and 12% of women in this group claimed consumption of these foods 4 or more times a day. In general, a higher percentage of those in the least deprived group met the targets for the key foods.

Trends to increasing consumption of fruit and vegetables and fish were in the right direction, but the targets for consumption of certain key foods were met by a minority of the population. The progress towards the target for fruit and vegetables showed widening social gradients with time.

In addition to their possible direct biological effects, plasma carotenoids can be used as biochemical markers of fruit and vegetable consumption for identifying diet–disease associations in epidemiological studies. Few studies have compared levels of these carotenoids between countries in Europe.

Our aim was to assess the variability of plasma carotenoid levels within the cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC).

Plasma levels of six carotenoids – α-carotene, β-carotene, β-cryptoxanthin, lycopene, lutein and zeaxanthin – were measured cross-sectionally in 3043 study subjects from 16 regions in nine European countries. We investigated the relative influence of gender, season, age, body mass index (BMI), alcohol intake and smoking status on plasma levels of the carotenoids.

Mean plasma level of the sum of the six carotenoids varied twofold between regions (1.35μmoll−1 for men in Malmö, Sweden vs. 2.79μmoll−1 for men in Ragusa/Naples, Italy; 1.61μmoll−1 for women in The Netherlands vs. 3.52μmoll−1 in Ragusa/Naples, Italy). Mean levels of individual carotenoids varied up to fourfold (α-carotene: 0.06μmoll−1 for men in Murcia, Spain vs. 0.25μmoll−1 for vegetarian men living in the UK). In multivariate regression analyses, region was the most important predictor of total plasma carotenoid level (partial R2=27.3%), followed by BMI (partial R2=5.2%), gender (partial R2=2.7%) and smoking status (partial R2=2.8%). Females had higher total carotenoid levels than males across Europe.

Plasma levels of carotenoids vary substantially between 16 different regions in Italy, Greece, Spain, France, Germany, the UK, Sweden, Denmark and The Netherlands. Compared with region of residence, the other demographic and lifestyle factors and laboratory measurements have limited predictive value for plasma carotenoid levels in Europe.

To investigate changes in the consumption of fruits and vegetables in work-site canteens using the tools of continuous quality improvement, and to gain knowledge of practical strategies being effective in increasing the consumption.

Study design included baseline data collection, an 8 h training session for all canteen staff, goal setting, strategy development and implementation for each canteen, end-point data collection and a follow-up data collection 4 months from the end-point (1 year from baseline). The main outcome measurement was average grams of fruits and vegetables per lunch meal served per customer (net weight; potatoes not included).

Five workplaces in Denmark: a military base, an electronic component distributor, a bank, a town hall and a waste-handling facility.

Work-site canteen managers, staff and customers.

There were significant increases in the total consumption of fruits and vegetables for all five work-site canteens from baseline to end-point, 70 g per customer on average (67, 54, 39, 88 and 103 g, respectively). The follow-up data collection showed that the canteens either maintained or significantly increased consumption, the average increase being 95 g per customer compared with baseline (77, 60, 86, 70 and 183 g, respectively).

This study demonstrates a large potential for work-site canteens to increase customers' intake of fruits and vegetables at lunch and suggests a broad spectrum of strategies to compose meals that are both rich in fruits and vegetables and attractive to customers.

Research in industrialised countries has documented a high prevalence of underreported energy intakes associated with characteristics such as obesity. This paper examines the prevalence, patterns and impact of energy under- and overreporting on diet–obesity relationships in a middle-income developing country.

A 70-item food-frequency questionnaire was used. Underreporters had reported energy intakes < 1.35 × basal metabolic rate (BMR), overreporters > 2.4 × BMR. Multinomial models were used to identify characteristics associated with implausible reporting. Intakes were compared across reporting groups to assess evidence of bias. Associations between diet and obesity were compared with and without adjustment for implausible reporting.

Spanish Town, neighbouring the capital city of Kingston, Jamaica.

Eight hundred and ninety-one Jamaican adults, aged 25–75 years, were randomly recruited.

More women than men (38.6% vs. 22.5%) underreported, but more men overreported energy (23.7% vs. 16.0%). Underreporting was positively associated with obesity, special diets, smoking and age; age was inversely associated with overreporting. Underreporters estimated lower energy from potentially socially undesirable food groups (e.g. snacks) and higher intakes of ‘healthy’ foods (e.g. fruit) than did plausible reporters. For some of these food groups, significant differences in intakes among normal-weight versus obese subjects observed among plausible reporters were absent when implausible reporters were included. In models of food group–obesity associations, adjusting for implausible energy yielded more credible results that more closely resembled findings in plausible reporters.

Energy under- and overreporting are highly prevalent in Jamaica. Adjusting for implausible reporting may help to reduce bias in diet–health outcome associations.

The overall objective of this study was to evaluate and provide evidence and recommendations on current published literature about diet and lifestyle in the prevention of type 2 diabetes.

Epidemiological and experimental studies, focusing on nutritional intervention in the prevention of type 2 diabetes are used to make disease-specific recommendations. Long-term cohort studies are given the most weight as to strength of evidence available.

Numerous clinical trials and cohort studies in low, middle and high income countries are evaluated regarding recommendations for dietary prevention of type 2 diabetes. These include, among others, the Finnish Diabetes Prevention Study, US Diabetes Prevention Program, Da Qing Study; Pima Indian Study; Iowa Women's Health Study; and the study of the US Male Physicians.

There is convincing evidence for a decreased risk of diabetes in adults who are physically active and maintain a normal body mass index (BMI) throughout adulthood, and in overweight adults with impaired glucose tolerance who lose weight voluntarily. An increased risk for developing type 2 diabetes is associated with overweight and obesity; abdominal obesity; physical inactivity; and maternal diabetes. It is probable that a high intake of saturated fats and intrauterine growth retardation also contribute to an increased risk, while non-starch polysaccharides are likely to be associated with a decreased risk. From existing evidence it is also possible that omega-3 fatty acids, low glycaemic index foods and exclusive breastfeeding may play a protective role, and that total fat intake and trans fatty acids may contribute to the risk. However, insufficient evidence is currently available to provide convincing proof.

Based on the strength of available evidence regarding diet and lifestyle in the prevention of type 2 diabetes, it is recommended that a normal weight status in the lower BMI range (BMI 21–23) and regular physical activity be maintained throughout adulthood; abdominal obesity be prevented; and saturated fat intake be less than 7% of the total energy intake.

To examine ethnic differences in body mass index (BMI), food habits and physical activity, and determine the factors contributing to differences in BMI.

In 2000–2001, 7343 (response rate 88%) 15- and 16-year-old students, enrolled in lower secondary schools in Oslo, participated in the cross-sectional Oslo Health Study. Of these participants, 1719 were defined as ethnic minorities.

Significant gender and ethnic differences in mean BMI were observed. Of the ethnic minority adolescents, 5.8% were underweight (<5th percentile of the US Centers for Disease Control and Prevention (CDC)/National Center for Health Statistics (NCHS) reference distribution) and 9.1% were overweight (>85th percentile of the US CDC/NCHS reference distribution). BMI was not significantly associated with either socio-economic factors or physical activity. Food habits and physical activity differed with ethnicity but not with socio-economic factors. An ordinal regression showed that girls from East Asia (odds ratio (OR) 0.4) and boys from sub-Saharan Africa (OR 0.4) had lower BMI than the Western group. Among girls, higher BMI was associated with less frequent consumption of chocolates and sweets, full-fat milk and breakfast (OR 2.4, 1.7 and 1.7, respectively). Higher BMI, for both boys and girls, was associated with current and past dieting (OR 3.7 and 4.2, respectively).

Adolescent food habits and physical activity varied by gender and ethnicity but not with socio-economic factors. BMI was associated with ethnicity, gender and food habits, but no significant relationship was observed with socio-economic factors or physical activity. Ethnicity, in addition to gender, should be taken into consideration when studying BMI and associated factors among adolescents.

To examine the adoption of feeding recommendations among caregivers of children recuperating from malnutrition and assess the determinants of growth of children attending a nutrition rehabilitation centre (NRC) in Accra, Ghana.

Longitudinal study in which attendance and maternal programme participation were recorded daily and children's anthropometry and dietary intake were measured at four time points (admission, interim, exit, post-exit) at the NRC and participants' homes.

NRCs at four polyclinics and participants' homes in Accra, Ghana.

One hundred and eight caregivers and their 116 children referred to an NRC between November 1999 and July 2000.

Most caregivers attended the NRC sporadically (effective length of stay was 1.4 ± 0.1 months). Use of NRC-promoted foods in the home after discharge was low due to inaccessibility of the food items, lack of preparation knowledge or money, child preferences and the common practice of purchasing ready-to-eat foods. Although there were significant increases in children's weight-for-age (P = 0.048) and weight-for-height (P = 0.002) Z-scores between enrolment and discharge, most children discontinued programme participation before adequate recuperation.

The NRC education did not address the use of street foods for child feeding and was unsuccessful in changing in-home feeding behaviour. The prominence of street foods in children's diets warrants re-evaluation of the NRC's educational approaches to enhance their responsiveness to caregivers' needs and effectiveness for the continued recuperation of malnourished children at home. NRC feeding strategies need improvement to ensure adequate provision of energy and nutrients to support catch-up growth in children.

To review the impact of agriculture interventions on nutritional status in participating households, and to analyse the characteristics of interventions that improved nutrition outcomes.

We identified and reviewed reports describing 30 agriculture interventions that measured impact on nutritional status. The interventions reviewed included home gardening, livestock, mixed garden and livestock, cash cropping, and irrigation. We examined the reports for the scientific quality of the research design and treatment of the data. We also assessed whether the projects invested in five types of ‘capital’ (physical, natural, financial, human and social) as defined in the Sustainable Livelihoods Framework, a conceptual map of major factors that affect people's livelihoods.

Most agriculture interventions increased food production, but did not necessarily improve nutrition or health within participating households. Nutrition was improved in 11 of 13 home gardening interventions, and in 11 of 17 other types of intervention. Of the 19 interventions that had a positive effect on nutrition, 14 of them invested in four or five types of capital in addition to the agriculture intervention. Of the nine interventions that had a negative or no effect on nutrition, only one invested in four or five types of capital.

Those agriculture interventions that invested broadly in different types of capital were more likely to improve nutrition outcomes. Those projects which invested in human capital (especially nutrition education and consideration of gender issues), and other types of capital, had a greater likelihood of effecting positive nutritional change, but such investment is neither sufficient nor always necessary to effect change.

To analyse factors associated with breast-feeding and use of sweetened drinks at 12 months, and to compare dietary habits among breast-fed and non-breast-fed infants.

Data were collected by a semi-quantitative food-frequency questionnaire filled in by the parents.

National dietary survey in Norway.

In total, 1932 12-month-old infants were included.

At 12 months, 36% of the infants were breast-fed. The odds of breast-feeding at this age were more than doubled both for mothers ≥35 years compared with mothers <25 years and for mothers in the highest educational group compared with mothers in the lowest. A negative association was found for maternal smoking, and the odds of breast-feeding were 40% lower for mothers who smoked than for non-smokers. Some dietary differences were observed between breast-fed and non-breast-fed infants apart from intake of milk. In particular, breast-fed infants had a significantly lower daily intake of sweetened drinks than non-breast-fed infants and a 16% lower mean daily intake of added sugars (P < 0.001). Furthermore, breast-fed infants had 30% higher odds of not receiving sweetened drinks daily, compared with non-breast-fed infants.

Maternal age, education and smoking status were important factors for breast-feeding at 12 months. Breast-fed infants had lower intakes of sweetened drinks and added sugars than non-breast-fed infants. From a public health perspective, continued promotion of breast-feeding is needed to reduce inequalities in breast-feeding. Moreover, prevention of high intakes of sweetened drinks and added sugars should start in infancy.

As a means to prevent neural tube defects (NTDs), women planning pregnancy in Denmark are recommended to take a dietary supplement of 400 μg folic acid daily during the periconceptional period. We examined compliance with this recommendation in a national survey.

Cohort study on pregnant women in Denmark.

The Danish National Birth Cohort (DNBC).

From November 2000 to February 2002, 22 000 pregnant women were recruited for DNBC. Use of dietary supplements was recorded at enrolment. Compliance with the recommendation was related to an information campaign that took place during the second half of 2001, and to lifestyle factors provided in a telephone interview by the end of the first trimester of pregnancy.

An increase was seen in the proportion of women complying with the recommendation in the study period and this coincided with the information campaign events. However, even at the end of the period, only 22.3% of the women who had planned their pregnancy fully complied with the recommendation. No increase at all was seen in periconceptional folic acid use among women with unplanned pregnancies. Young age, low education and smoking were identified as factors that determined non-compliance.

Alternative and more effective strategies are needed if the Danish population is to benefit fully from the knowledge that folic acid prevents NTDs. Future strategies should not only target vulnerable groups, such as the less educated and the young, but also women who get pregnant without planning this. The only possible way to reach the last group may be through fortification of foods with folic acid.

To evaluate the efficacy and feasibility of using a computer-based teaching tool (http://www.coolfoodplanet.org) for nutrition and lifestyle education developed for primary school children.

This was a 2-week school-based intervention in third and fourth grades. The study design was multi-factorial with repeated measures of nutrition knowledge, at three points in time, of dependent samples from control and intervention groups. Control schools (n=7) used ‘traditional’ nutrition education materials and intervention schools (n=8) additionally used the computer-based educational tool. Qualitative information was collected in focus group discussions with student teachers and pupils, and by observing the nutrition lessons.

Pupils aged 8–11 years (n=271) from participating schools in Vienna, Austria.

Nutrition knowledge increased significantly in both intervention and control schools, irrespective of the teaching tool used (P<0.001). The significant effect was maintained at 3 months' follow-up. There was no detectable difference in nutrition knowledge post intervention or at follow-up between the two study groups. In intervention schools, younger pupils (8–9 years) had better nutrition knowledge than older pupils (10–11 years) (P=0.011).

This computer-based tool increases the possibilities of school-based nutrition education. If the tool's weaknesses identified during the formative evaluation are eliminated, it has the potential to make learning about nutrition more enjoyable, exciting and effective. This is of great importance considering that ‘healthy’ nutrition is not necessarily a topic that easily attracts pupils' attention and in view of the potential long-term health benefits of early and effective nutrition education.