To identify challenges in translating scientific evidence of a nutrient and health relationship into mandatory food fortification policy.

A case study approach was used in which available evidence associated with the folate–neural tube defect relationship was reviewed against the Australia New Zealand Food Regulation Ministerial Council's Policy Guideline for mandatory food fortification.

Three particular challenges were identified. The first is knowing when and how to act in the face of scientific uncertainty. The second is knowing how to address the special needs of at-risk individuals without compromising the health and safety of the population as a whole. The third is to ensure that a policy is sufficiently monitored and evaluated.

Despite the availability of compelling evidence of a relationship between a particular nutrient and a health outcome, a definitive policy response may not be apparent. Judgement and interpretation inevitably play significant roles in influencing whether and how authorities translate scientific evidence into mandatory food fortification policy. In relation to the case study, it would be prudent to undertake a risk–benefit analysis of policy alternatives and to implement nutrition education activities to promote folic acid supplement use among the target group. Should mandatory folate fortification be implemented, comprehensive monitoring and evaluation of this policy will be essential to know that it is implemented as planned and does more good than harm. In relation to mandatory food fortification policy-making around the world, ongoing national nutrition surveys are required to complement national policy guidelines.

To set out a policy analysis of food taxes as a way of influencing food consumption and behaviour.

The study draws on examples of food taxes from the developed world imposed at national and local levels. Studies were identified from a systemised search in six databases with criteria designed to identity articles of policy relevance.

The dominant approach identified from the literature was the imposition of food taxes on food to raise general revenue, such as Value Added Tax in the European Union. Food taxes can be applied in various ways, ranging from attempts to directly influence behaviour to those which collect taxes for identified campaigns on healthy eating through to those applied within closed settings such as schools. There is a case for combining taxes of unhealthy foods with subsidies of healthy foods. The evidence from the literature concerning the use and impact of food taxes on food behaviour is not clear and those cases identified are mainly retrospective descriptions of the process. Many food taxes have been withdrawn after short periods of time due to industry lobbying.

Small taxes with the clear purpose of promoting the health of key groups, e.g. children, are more likely to receive public support. The focus of many tax initiatives is unclear; although they are generally aimed at consumers, another focus could be food manufacturers, using taxes and subsidies to encourage the production of healthier foods, which could have an effect at a population level. Further consideration needs to be given to this aspect of food taxes. Taxing food (and subsidies) can influence food behaviour within closed systems such as schools and the workplace.

A 5-year nationwide mass media campaign aimed at prevention of overweight was organised from 2002 onwards. The present study evaluates the first campaign, which was aimed primarily at increasing awareness of weight gain.

Data were collected by telephone interview in four independent cross-sectional surveys among non-obese Dutch adults aged 25–35 years (total n = 1949) for statistical analyses. Awareness of personal body-weight status, overweight-related risk perceptions, attitudes towards weight-gain prevention, motivation to prevent weight gain and self-reported body mass index (BMI) were measured in each survey. Campaign exposure was assessed in the post-intervention surveys. To identify intervention effects over time multiple linear and logistic regression analyses were used, adjusted for secular time effects and age.

After the campaign about 65% of the respondents knew about the campaign. The campaign was associated with more positive attitudes towards the prevention of weight gain (β = 0.16; P ≤ 0.01) and higher self-reported BMI (β = 0.14; P ≤ 0.01).

The results suggest that the first campaign reached a large proportion of the population and initiated some positive change in attitudes, but did not achieve significant improvements in other determinants of weight-gain prevention among non-obese young adults.

The aim of the study was to investigate the relative importance of personal and social environmental predictors of the consumption of fruit, high-fat snacks and breakfast.

A school-based cross-sectional survey. Data were collected through written questionnaires.

Students from eight schools in the southern part of The Netherlands.

Six hundred and one students from preparatory secondary vocational education schools.

About a quarter of the variation in actual behaviours and intentions to change the behaviours could be explained. Stepwise multiple regression analysis revealed that, for all three behaviours, higher intention to change was especially associated with a more positive attitude and subjective norm, and higher intentions to increase fruit intake with more positive self-efficacy expectations. With regard to actual consumption, a more positive attitude towards eating fruit was the only significant correlate of a higher consumption of fruit. A more positive attitude towards eating high-fat snacks, perceived lower intake of the mother, and higher food availability and accessibility were associated with consumption of high-fat snacks, and a more positive attitude to breakfast more frequently was associated with more frequent breakfast consumption.

The results indicate that adolescents’ attitudes are the most important determinants of different health-related eating behaviours and intentions to change. Interventions promoting a healthy diet for adolescents should include creative strategies to achieve positive associations with healthy dietary changes.

To study changes in lifestyle in relation to changes in body weight and waist circumference associated with occupational retirement in men.

A prospective cohort study with 5 years of follow-up. At baseline and at follow-up, questionnaires were completed and body weight and waist circumference were measured.

The Doetinchem Cohort Study, consisting of inhabitants of Doetinchem, a town in a rural area of The Netherlands.

In total 288 healthy men aged 50–65 years at baseline, who either remained employed or retired over follow-up.

The effect of retirement on changes in weight and waist circumference was dependent on type of former occupation. Increase in body weight and waist circumference was higher among men who retired from active jobs (0.42 kg year−1 and 0.77 cm year−1, respectively) than among men who retired from sedentary jobs (0.08 kg year−1 and 0.23 cm year−1, respectively). Weight gain and increase in waist circumference were associated with a decrease in fruit consumption and fibre density of the diet, with an increase in frequency of eating breakfast, and with a decrease in several physical activities, such as household activities, bicycling, walking and doing odd jobs.

Retirement was associated with an increase in weight and waist circumference among those with former active jobs, but not among those with former sedentary jobs. Retirement may bring opportunities for healthy changes in diet and physical activity, which could be used in health promotion programmes.

The fluid recommendation for adults aged 70+ years has been criticised on the basis of a low prevalence of dehydration in community-dwelling older adults. This study explores whether the low prevalence might reflect limitations of individual dehydration indices.

Cross-sectional data on plasma sodium, blood urea nitrogen (BUN), creatinine, glucose and potassium were used to classify 1737 participants of the 1992 Established Populations for Epidemiologic Studies of the Elderly (EPESE) (70+ years) according to multiple dehydration indices. Associations between dehydration indices, health and functional status were evaluated.

Depending on the indicator used, the prevalence of dehydration ranged from 0.5% for hypotonic hypovolaemia only (plasma tonicity <285 mOsm l−1 with orthostatic hypotension) to 60% with dehydration defined as either plasma sodium ≥145 mEq l−1, BUN/creatinine ratio ≥20, tonicity ≥295 mOsm l−1, or hypotonic hypovolaemia. Elevated tonicity and BUN/creatinine ratio were respectively associated with chronic disease and functional impairment.

The true prevalence of dehydration among community-dwelling adults may be low or high, depending on the indicator(s) used to define dehydration. Before we can pinpoint a generalisable prevalence of dehydration for community-dwelling seniors and draw conclusions about fluid recommendations, validation studies of dehydration indices and longitudinal studies of dehydration, health and functional status are needed.

To examine and analyse consumption changes over time of 24 food items between Sardinia and Malta.

The data were collected in 2001 in Sardinia and 2002 in Malta.

A structured qualitative questionnaire, articulated around four main themes: food supply, transformation, preparation and consumption habits, was administered by face-to-face interviews with the help of a local person. It encompassed mainly open-ended questions, which allowed us to measure factors contributing to change.

Thirty mother–daughter pairs were interviewed in each insular territory.

Despite a common trend revealing a shift away from cereals, pulses and potatoes to the benefit of meat products, fats and sugar, our results showed contrasting evolutions in food consumption between both insular societies. Fruit and vegetables, olive oil and fish, which are part of the main features of the Mediterranean diet, were among the top foods for which consumption frequency has increased in Sardinia. In Malta, besides an increase in olive oil and vegetable consumption, cheeses and desserts showed the highest increase. Along with modernity and improved living conditions, enhanced commercial availability and increased diversity of food preparation were also identified as factors contributing to food consumption changes.

Although the Sardo-Mediterranean model is evolving under the impact of modernisation, it is not disappearing. In Malta, however, modernity has led to a more sudden shift from a state of food shortage to one of affluence, but in a cultural context where the identity is no longer Mediterranean but Anglo-Saxon.

Random errors, from any source, will attenuate epidemiological risk estimates. Before we launched the Shanghai Men's Health Study (SMHS), a large population-based cohort study investigating the diet–cancer association among Chinese men, a dietary calibration study was conducted among 96 men aged 40–75 years (mean age 56.5 years), with biweekly 24-hour dietary recalls (24HDRs) implemented over a 1-year period. Data from this study were analysed to evaluate the nature and magnitude of variances for intake of 26 nutrients among SMHS participants, to compare variance ratios of 26 nutrients among Chinese men and women and individuals in other studies, and to estimate the number of 24HDRs required for future dietary calibration studies in similar populations.

Ninety-six healthy, free-living men in Shanghai were administered biweekly 24HDR interviews 24 times over a 1-year period. To assess between-individual and within-individual contributions to variance, a mixed effects model was fitted and ratios of within-individual to between-individual dietary intake variances were computed.

Shanghai, China.

In agreement with reports from studies conducted in the USA and many other countries, we found that within-individual variances were usually larger than between-individual variances in dietary intake for all nutrients. The sum of all other variation (e.g. weekday and weekend, seasonal, interviewer) accounted for less than 5% of total variation. Ratios of within- to between-individual variances (for log-transformed data) ranged from 1.25 for carbohydrate intake to near 8 for δ-tocopherol intake.

The results of this study suggest that among middle-aged and elderly Chinese men in Shanghai, within- and between-individual variation account for more than 95% of the total variation for 26 nutrients. Further dietary validation studies in the same population could be adequately carried out with only 12 days of dietary recalls, if 100 participants were enrolled.

Green tea has been widely acknowledged in Japan to induce a pleasurable mental feeling. Recent laboratory studies have suggested positive psychological effects as a result of consuming green tea. The present study examined whether green tea consumption in everyday life in Japan is associated with positive mental health.

A cross-sectional study was performed in February–March 2002.

The subjects of the study consisted of a general population of 600 Japanese aged 20–69 years. Responses of 380 subjects, obtained by home-visit interview, were analysed. The questionnaire inquired about consumption of brewed green tea and other beverages, perceived mental health status, lifestyle and others. The 12-item General Health Questionnaire (GHQ 12) was used for the assessment of mental ill-health (GHQ score ≥4).

After adjustments for age, area, perceived mental stress, lifestyle and daily caffeine intake, the consumption of brewed green tea was not statistically associated with any decrease in risk of mental ill-health among either males or females (odds ratio (OR) = 0.78, 95% confidence interval (CI) = 0.47–1.29 for males; OR = 0.77, 95% CI = 0.51–1.14 for females). Daily caffeine intake (100 mg) inclusive of green tea, black tea, coffee and other caffeine-containing beverages was associated with a higher risk of mental ill-health among females (OR = 1.26, 95% CI = 1.01–1.56).

The results provide population-based evidence on the consumption of brewed green tea in everyday life and mental health, together with information on consumption patterns of various beverages and lifestyles.

We aimed at examining the association between dietary constituents and risk of cutaneous melanoma.

In an area of northern Italy we recruited 59 newly diagnosed melanoma patients and 59 age- and sex-matched population controls, to whom we administered a validated semi-quantitative food-frequency questionnaire.

We found an excess risk of melanoma in subjects with a higher energy-adjusted intake of total polyunsaturated fatty acids and, in particular, of linoleic acid (relative risk = 2.16 for intake in the highest tertile compared with the lowest tertile, P for linear trend = 0.061). Conversely, disease risk was inversely associated with the consumption of soluble carbohydrates (relative risk = 0.34 for intake in the upper vs. the lowest tertile adjusting for total energy intake, P for linear trend = 0.046). No other dietary factors, including alcohol, vitamins and trace elements, correlated with melanoma risk. The association of melanoma risk with linoleic acid and soluble carbohydrates intakes was further strengthened in multivariate analysis, and when analysis was limited to females.

Overall, these results indicate that an excess energy-adjusted intake of linoleic acid and a lower consumption of soluble carbohydrates may increase melanoma risk.

To validate energy intake (EI) estimated from pre-coded food diaries against energy expenditure (EE) measured with a validated position-and-movement monitor (ActiReg®) in groups of 13-year-old Norwegian schoolchildren.

Two studies were conducted. In study 1 the monitoring period was 4 days; participants recorded their food intake for four consecutive weekdays using food diaries and wore the ActiReg® during the same period. In study 2 the monitoring period was 7 days; participants recorded their food intake for four consecutive days but wore the ActiReg® for a whole week.

Participants were recruited from grade 8 in a school in and one outside Oslo (Norway).

Forty-one and 31 participants from study 1 and 2, respectively, completed the study.

The group average EI was 34% lower than the measured EE in study 1 and 24% lower in study 2. The width of the 95% confidence limits of agreement in a Bland–Altman plot for EI and EE varied from -0.2 MJ to 8.2 MJ in study 1 and from -2.3 MJ to 6.9 MJ in study 2. The Pearson correlation coefficients between reported energy intake and expenditure were 0.47 (P = 0.002) in study 1 and 0.74 (P < 0.001) in study 2.

The data showed that there was substantial variability in the accuracy of the food diary at the individual level. Furthermore, the diary underestimated the average energy intake. The ability of the food diary to rank individuals according to energy intake was found to be good in one of the studies and moderate in the other.

To describe the consequences of systematic reporting bias by the obese for diet–disease relationships.

The present report used 24-hour urinary nitrogen and estimates of 24-hour energy expenditure to assess error in diet reporting, and examined the consequence of accounting for this error for associations between dietary fat intake and serum low-density lipoprotein (LDL)-cholesterol.

Sub-study to the Danish MONICA (Monitoring Trends and Determinants in Cardiovascular Disease) project, carried out in 1987–1988.

A random sub-sample of the adult Danish male population (n = 152).

Correcting dietary fat for underreporting error weakened, rather than strengthened, the association between dietary fat intake and LDL-cholesterol by reducing the slope of the regression from β = 3.4, P = 0.02 to β = 2.7, P = 0.04.

This example illustrates that systematic underreporting of dietary fat by high-risk groups such as the obese may produce an overestimated association. These results imply that previous epidemiological studies showing a positive association between percentage of energy from fat and other health outcomes, e.g. cancer and heart disease, may have overestimated the negative effects of a high-fat diet. If we were able to correctly assess dietary fat intake in general populations, recommendations for fat intake may be more liberal than the 30% suggested today. Improved assessment of fat intake in epidemiological studies is necessary for future development of evidence-based recommendations for diet and health.