Validation of the 2 × 24 h recall method and a 7-d web-based food diary against doubly labelled water in Danish adults.

The European Food Safety Authority has suggested that EU countries implement the 2 × 24 h diet recall (2 × 24 h DR) method and physical activity (PA) measurements for national dietary surveys. Since 2000, Denmark has used 7 d food diaries (7 d FD) with PA questionnaires and measurements. The accuracy of the reported energy intakes (EI) from the two diet methods, pedometer-determined step counts and self-reported time spent in moderate-to-vigorous PA (MVPA) were compared with total energy expenditure measured by the doubly labelled water (TEEDLW) technique and with PA energy expenditure (PAEE), respectively. The study involved fifty-two male and sixty-eight female volunteers aged 18-60 years who were randomly assigned to start with either the 24 h DR or the web-based 7 d FD, and wore a pedometer for the first 7 d and filled in a step diary. The mean TEEDLW (11·5 MJ/d) was greater than the mean reported EI for the 7 d FD (9·5 MJ/d (P < 0·01)) but the same as the 2 × 24 h DR (11·5 MJ/d). The proportion of under-reporters was 34 % (7 d FD) and 4 % (2 × 24 h DR). Most participants preferred the 7 d DR as it was more flexible, despite altering their eating habits. Pearson's correlation between steps corrected for cycling and PAEE was r = 0·44, P < 0·01. Spearman's correlation for self-reported hours spent in MVPA and PAEE was r = 0·58, P < 0·01. The 2 × 24 h DR performs better than the existing 7 d FD method. Pedometer-determined steps and self-reported MVPA are good predictors of PAEE in adult Danes.

Dietary supplements increase the risk of excessive micronutrient intakes in Danish children.

PURPOSE: Dietary supplement use is common in Northern Europe. Many dietary supplements contain 100% of nutrient reference values (NRV) of micronutrients. This study investigates the contribution of dietary supplements to micronutrient intake, the prevalence of excess intake of micronutrients, and parental characteristics of dietary supplement use in Danish children. METHODS: Data on 499 4-10-year-old children from the Danish National Survey of Diet and Physical Activity 2011-2013 were analysed using non-parametric statistics to compare micronutrient intake from the diet and dietary supplements to the reference intake (RI), and to the tolerable Upper Intake Level (UL) for users and non-users of dietary supplements. Furthermore, characteristics of the parents of users and non-users of dietary supplements were examined by logistic regression analysis. RESULTS: Sixty-four percent of the children were dietary supplement users. Multivitamin-mineral supplements were the most frequently used type of supplement (60%). Children of never-smokers were more likely to use supplements than children of smokers. Users had significantly higher total intakes of 15 micronutrients compared to non-users. Intakes of vitamin A, zinc, and iodine from the diet alone exceeded ULs in 12-30% of the children. Use of dietary supplements gave rise to 21-73% of children in exceedance of the aforementioned three ULs as well as the UL for iron (6-45%). CONCLUSION: Dietary supplement use was common among 4-10-year-old Danish children and resulted in a considerable proportion of users exceeding the ULs for vitamin A, zinc, iodine, and iron. The long-term health consequences of exceeding these ULs for children are unknown.

The Danish National Survey of Diet and Physical Activity (DANSDA) 1995-2011-2013: Study design, study participants, participation rate and underreporting.

AIM: This study describes the study design, study participants, participation rate and underreporting in the Danish National Surveys of Diet and Physical Activity (DANSDA) from 1995 to 2011-2013. METHODS: DANSDA are government-funded surveys of food and nutrient intake, physical activity and lifestyle, undertaken to support nutritional policy, risk assessment and public health research. The surveys are cross-sectional based on primarily simple random samples (ages 1-80 years in 1995, 4-75 years in 2000-2013) drawn from the Danish Civil Registration System. Approximately 4800 individuals in 1995, 8200 in 2000-2002, 8400 in 2003-2008 and 7300 in 2011-2013 were invited to participate. Participants completed a seven-day food diary, a physical activity questionnaire (2000-2008), a step diary (2011-2013) and a face-to-face interview. Self-reported anthropometrics (1995-2013) were supplemented with device-based measures (2011-2013). Pedometers were included in 2011-2013. RESULTS: The number of participants included per survey round was 3100-4400. Participant rates decreased from 66% (1995) to 54% (2011-2013). Non-participation was primarily refusal. Ages 18-30 years, 61-75 years (2000-2013), 61-80 years (1995) and low educated and individuals living alone were underrepresented. Underreporting of energy intake among adults ranged from 14% (1995) to 26% (2008). CONCLUSIONS: The methods in DANSDA have been developed to include device-based measures on physical activity and anthropometrics. This has improved the applicability of the results of the survey. The participation rate has fallen, which has affected sample representativity, and underreporting has increased. Future DANSDA surveys should explore and consider new initiatives to counteract non-response and underreporting, with the aim of enhancing data representativeness and applicability.

The health impact of substituting unprocessed red meat by pulses in the Danish diet.

BACKGROUND: Diets consisting of high amounts of animal-based protein have been associated with adverse public health effects and are often deemed environmentally unsustainable. Therefore, replacing red meat by pulses has been proposed to reduce the adverse impact on human health and environment. However, unprocessed red meat is an important source of nutrients, such as vitamin B12, iron, zinc and selenium, and the substitution may have negative impact on nutrient adequacy. METHOD: Using a risk-benefit assessment (RBA) approach, we, therefore, estimated the health impact of substituting unprocessed red meat by pulses on the burden of non-communicable diseases in Denmark, using Disability-Adjusted Life Years (DALY). Furthermore, we assessed the impact of the substitution on nutrient adequacy. RESULTS: We found that 187 (95% UI: 209; 168) healthy years of life could be gained per 100,000 individuals per year by substituting 100% of unprocessed red meat by pulses in the Danish diet. We found a decrease in the intake of vitamin B12, zinc and selenium due to the substitution. An additional 10% of the Danish population will become at risk of vitamin B12 and selenium inadequacy, and an additional 20% will be at risk of zinc inadequacy due to the substitution. For iron, a small decrease in the proportion at risk of inadequacy was found. CONCLUSION: Substitution of unprocessed red meat by pulses was estimated to provide a beneficial health impact on the burden of non-communicable disease, expressed in DALY. Additionally, it was found that the complete substitution will lead to a higher risk of nutrient inadequacies.

Optimising healthy and safe fish intake recommendations: a trade-off between personal preference and cost.

Individuals may perceive personalised dietary advice as more relevant and motivational than national guidelines. Personal preference and food cost are factors that can affect consumer decisions. The objective of this study was to present a method for modelling and analysing the trade-off between deviation from preference and food cost for optimised personalised dietary recommendations. Quadratic programming was applied to minimise deviation from fish preference and cost simultaneously with different weights on the cost for 3016 Danish adults (whose dietary intake and body weight were recorded in a national dietary survey). Model constraints included recommendations for EPA, DHA and vitamin D and tolerable levels for methyl mercury, dioxins and dioxin-like polychlorinated biphenyls. When only minimising deviation from preference, 50 % of the study population should be recommended to increase fish intake, 48 % should be suggested to maintain current consumption and 2 % should be suggested to decrease fish consumption. When only minimising cost, the vast majority (99 %) should be recommended to only consume herring, which is the least-expensive fish species. By minimising deviation from preference and cost simultaneously with different weights on the cost, personalised optimal trade-off curves between deviation from fish intake preference and fish cost could be generated for each individual in our study population, except for twenty-two individuals (0·7 %) whose contaminant background exposure was too high. In the future, the method of this paper could be applied in the personal communication of healthy and safe food recommendations that fit the preferences of individual consumers.

Use of Mathematical Optimization Models to Derive Healthy and Safe Fish Intake.

Background: Recommended fish intake differs substantially from observed fish intake. In Denmark, ∼15% of the population consumes the state-recommended fish intake. How much fish individuals eat varies greatly, and this variation cannot be captured by considering the fish intake of the average population. Objective: We developed a method intended to provide realistic and achievable personalized dietary recommendations based on an individual's body weight and current fish intake. The objective of the study was to propose specific fish intake levels for individuals that meet the recommendations for eicosapentaenoic acid, docosahexaenoic acid, and vitamin D without violating the permitted intake recommendations for methyl mercury, dioxins, and polychlorinated biphenyls. Methods: Two mathematical optimization models were developed that apply quadratic programming to model personalized recommended fish intake, fulfilling criteria on nutrients and contaminants, while simultaneously deviating as little as possible from observed individual intake. A recommended intake for 8 fish species was generated for each individual in a group of 3016 Danes (1552 women and 1464 men, aged 18-75 y), whose fish intakes and body weights were known from a national dietary survey. Results: Individual, personal dietary recommendations were successfully modeled. Modeled fish intake levels were compared to observed fish intakes. For women, the average proposed increase in fish intake was 14 g/wk for lean fish and 63 g/wk for fatty fish; and for men these numbers were 12 and 55 g/wk, respectively. Conclusions: Using fish intake as an example, we show how quadratic programming models may be used to advise individual consumers how to optimize their diet, taking both benefits and risks into account. This approach has the potential to increase compliance with dietary guidelines by targeting the individual consumers and minimizing the need for large and ultimately unrealistic behavior changes.

Personalised fish intake recommendations: the effect of background exposure on optimisation.

National dietary guidelines are directed at the general population. However, these guidelines may be perceived as unrealistic by a substantial part of the population, as they differ considerably from individual consumption patterns and preferences. Personalised dietary recommendations will probably improve adherence, and it has been shown that these recommendations can be derived by mathematical optimisation methods. However, to better account for risks and benefits of specific foods, the background exposure to nutrients and contaminants needs to be considered as well. This background exposure may come from other foods and supplements, and also from environmental sources like the air and the sun. The objective of this study was therefore to analyse the effect of including individual variation in background exposure when modelling personalised dietary recommendations for fish. We used a quadratic programming model to generate recommended fish intake accounting for personal preference by deviating as little as possible from observed individual intake. Model constraints ensure that the modelled intake meets recommendations for EPA, DHA and vitamin D without violating tolerable exposure to methyl mercury, dioxins and dioxin-like polychlorinated biphenyls. Several background exposures were analysed for 3016 Danish adults, whose food intakes and body weights were reported in a national dietary survey. We found that the lower nutrient constraints were critical for the largest part of the study population, and that a total of 55% should be advised to increase their fish intake. The modelled fish intake recommendations were particularly sensitive to the vitamin D background exposure.

Intake and sources of gluten in 20- to 75-year-old Danish adults: a national dietary survey.

PURPOSE: Celiac disease, an immunological response triggered by gluten, affects ~1 % of the Western population. Information concerning gluten intake in the general population is scarce. We determined intake of gluten from wheat, barley, rye and oat in the Danish National Survey of Diet and Physical Activity 2005-2008. The study population comprised a random cross-sectional sample of 1494 adults 20-75 years, selected from the Danish Civil Registration System. METHODS: Protein content in wheat, rye, barley and oat was determined from the National Danish Food Composition Table and multiplied with the amount of cereal used in recipes. Amount of gluten was calculated as amount of cereal protein ×0.80 for wheat and oat, ×0.65 for rye and ×0.50 for barley. Dietary intake was recorded daily during seven consecutive days in pre-coded food diaries with open-answer possibilities. RESULTS: Mean total gluten intake was 10.4 ± 4.4 g/day (10th-90th percentiles; 5.4-16.2 g/day), in men 12.0 ± 4.6 g/day and 9.0 ± 3.4 g/day in women. It was higher among men than among women in all age groups (20-75 years; P < 0.0001); however, this difference was eliminated when adjusting for energy intake. Intake of different gluten sources tended to be higher in men than in women with the exception of gluten from barley. Total gluten intake decreased with increasing age (P < 0.0001) as did gluten intake from wheat (P < 0.0001), whereas intake of gluten from rye (P < 0.0001) and barley (P = 0.001) increased with increasing age, also when adjusted for energy intake or body weight. CONCLUSION: This study presents representative population-based data on gluten intake in Danish adults. Total gluten intake decreased with increasing age.

Intake of macro- and micronutrients in Danish vegans.

BACKGROUND: Since information about macro- and micronutrient intake among vegans is limited we aimed to determine and evaluate their dietary and supplementary intake. METHODS: Seventy 18-61 years old Danish vegans completed a four-day weighed food record from which their daily intake of macro- and micronutrients was assessed and subsequently compared to an age-range-matched group of 1,257 omnivorous individuals from the general Danish population. Moreover, the vegan dietary and supplementary intake was compared to the 2012 Nordic Nutrition Recommendations (NNR). RESULTS: Dietary intake differed significantly between vegans and the general Danish population in all measured macro- and micronutrients (p < 0.05), except for energy intake among women and intake of carbohydrates among men. For vegans the intake of macro- and micronutrients (including supplements) did not reach the NNR for protein, vitamin D, iodine and selenium. Among vegan women vitamin A intake also failed to reach the recommendations. With reference to the NNR, the dietary content of added sugar, sodium and fatty acids, including the ratio of PUFA to SFA, was more favorable among vegans. CONCLUSIONS: At the macronutrient level, the diet of Danish vegans is in better accordance with the NNR than the diet of the general Danish population. At the micronutrient level, considering both diet and supplements, the vegan diet falls short in certain nutrients, suggesting a need for greater attention toward ensuring recommended daily intake of specific vitamins and minerals.

Misperception of body weight among overweight Danish adults: trends from 1995 to 2008.

OBJECTIVE: To examine changes in the prevalence of overweight and weight misperception among overweight Danes from 1995 to 2008, and to identify factors associated with weight misperception. DESIGN: Cross-sectional studies, in which data on self-reported weight, height and self-perception of overweight status were obtained through face-to-face interviews. 'Overweight' includes obesity. Weight misperception was defined as overweight individuals who did not perceive themselves as overweight. The χ 2 test was used to analyse changes over time and multiple logistic regression analysis was applied to identify factors associated with weight misperception. SETTING: The Danish National Survey of Diet and Physical Activity in three periods: 1995, 2000-2004 and 2005-2008. SUBJECTS: A random sample of 9623 Danes aged 15-75 years. RESULTS: The prevalence of overweight increased in men and women from 1995 to 2005-2008 (from 35·1 % to 43·0 %, P < 0·001). Concurrently, there was a reduction in the proportion of overweight men (from 77·5 % to 71·4 %, P = 0·001) and women (from 54·8 % to 51·9 %, P = 0·24) who misperceived their weight. Factors associated with weight misperception were 'never intend to eat healthily' (men), high levels of leisure-time physical activity, 'very good/excellent' self-rated health and survey year (higher misperception in 2000-2004 than 2005-2008; P < 0·05). CONCLUSIONS: The increase in overweight from 1995 to 2005-2008 was accompanied by a reduction in the proportion of overweight men misperceiving their weight. This may indicate that more men see overweight as a personally relevant health problem. Our findings also suggest that overweight individuals who are more physically active and have better self-rated health may not consider their excess weight a health problem.

Trends in overweight and obesity in Danish children and adolescents: 2000-2008--exploring changes according to parental education.

AIMS: To examine the hypotheses that an overall levelling off in the prevalence of overweight and obesity during the period 2000-2008 has occurred, and that increasing social inequality in overweight and obesity exists in a nationally representative sample of Danish children and adolescents. METHODS: The population comprised a random sample of 1849 children aged 4-14 years who participated in the Danish National Survey of Diet and Physical Activity in 2000-2002, 2003-2004 and 2005-2008. Parental education was chosen as an indicator of children's socioeconomic status. Body mass index (BMI) was calculated from parent-reported weight and height. Subjects were classified as overweight and obese according to the International Obesity Task Force age- and gender-specific BMI cut-off values. Crude prevalence estimates and logistic regression models were used to analyse trends in overweight and obesity as the main outcome measures. RESULTS: An increase was found in the crude prevalence of overweight (including obesity) in boys (12.8-21.7%, p = 0.0006), but not in girls (17.6-15.9%, p = 0.56), between 2000-2002 and 2005-2008. The prevalence of overweight increased significantly in boys of parents with low educational level only. A strong inverse social gradient in overweight and obesity was documented for boys and girls during the whole survey period. CONCLUSIONS: The present study showed an increase in the prevalence of overweight in Danish boys, but not in girls. This increase was due to increasing social inequality in overweight among boys. Public health initiatives aimed at preventing and reducing overweight and obesity should consider gender difference and especially target boys with parents of low educational level.

Disparities in dietary habits and physical activity in Denmark and trends from 1995 to 2008.

AIMS: To examine social disparities in dietary-, alcohol- and leisure-time physical activity habits in Danish adults from 1995 to 2008 and to test the hypothesis of widening disparities. METHODS: Four cross-sectional surveys of representative samples of the Danish population aged 20-75 years were analysed, a total of 7900 respondents. Dietary and alcohol habits were measured by a 7-day pre-coded food diary and physical activity and education by a face-to-face interview. Multivariate analyses were used to test associations between explanatory variables and response variables and the hypothesis of widening disparities. RESULTS: In all analyses, both diet quality and physical inactivity differed systematically with educational group and with healthier habits for the group with long education. Only for alcohol habits was an opposite social gradient seen. Disparities persisted over all time periods. The analyses using "The Concentration Index" did not change any of the conclusions. Gender also influenced diet quality. Men had dietary and alcohol habits furthest away from the guidelines. A trend of healthier habits was also found over the time period. CONCLUSIONS: Social disparities in diet quality and leisure-time physical activity were seen for all examined time periods and with no significant change therefore, there is no support to the hypothesis of widening social disparities in all educational groups some improvement of dietary habits was found, especially for those foods where comprehensive initiatives had taken place however, social disparities still exist there is an ongoing need to address these disparities in order to reduce social inequality in health.

Danish children born to parents with lower levels of education are more likely to become overweight.

AIM: Little is known about whether the socio-economic status of parents is linked to their children becoming overweight. This study examined the association between parents' educational level and overweight Danish children in a nationally representative sample. METHODS: Body mass index was calculated for a random sample of 512 children aged from four to 14 from the Danish National Survey of Diet and Physical Activity 2005-2008. Their parents provided weight and height data during an interview, together with details of their own educational level. Children were classified as overweight/obese in accordance with the International Obesity Task Force. Frequency estimates of prevalence and logistic regression models were used to correlate childhood overweight/obesity with the mothers' and fathers' educational levels as the main outcome measures. RESULTS: Danish mothers tended to be more highly educated than fathers and their educational level was inversely associated with their child being overweight, especially if it was a boy. However, the highest educational level of the parents was the only significant educational variable, suggesting that education was associated with overweight children irrespective of the gender of the parent. CONCLUSION: Public health initiatives should target parents with low educational levels to prevent, and reduce, social inequality in overweight children.

Changes in Diet and Physical Activity among 18-65-Year-Olds after the First National COVID-19 Lockdown in Denmark.

COVID-19 lockdowns affected everyday life significantly and made it challenging to achieve or maintain a healthy lifestyle. The aim of the present study was to examine longitudinal changes in Danish adults' eating habits and physical activity (PA) assessed during and after the first national lockdown in 2020. Furthermore, changes in body weight were examined during the first lockdown period. The whole diet (semi-quantitative Food Frequency Questionnaire), sociodemographic factors, moderate-to-vigorous intensity PA (MVPA), leisure screen time, anthropometrics, change in body weight, and stress level were assessed with a self-administered web-based questionnaire among 839 18-65-year-old Danes during and 5-6 months after the lockdown. Both favorable (decreased intake of saturated fat) and unfavorable (decreased intake of whole grain and fish, and increased intake of red meat) changes were found in the diet after the lockdown, while favorable changes in MVPA (increase in couples) and leisure screen time (decrease with a combined effect of family status and education) were found for PA. More Danish adults reported to gain weight (mean 3.0 kg) than to lose weight (mean 3.5 kg) during the first lockdown period (27% vs. 15%). The study showed favorable changes in PA and mixed results regarding diet among Danish adults after the lockdown. Furthermore, the first lockdown period unfavorably impacted the body weight of many Danes.

Quantifying benefits of the Danish transfat ban for coronary heart disease mortality 1991-2007: Socioeconomic analysis using the IMPACTsec model.

Denmark has experienced a remarkable reduction in CVD mortality over recent decades. The scale of the health contribution from the Danish regulation on industrially produced trans fatty acid (ITFA) has therefore long been of interest. Thus the objective was to determine health and equity benefits of the Danish regulation on ITFA content in Danish food, by quantifying the relative contributions of changes in ITFA intake, other risk factors and treatments on coronary heart disease (CHD) mortality decline from 1991 to 2007 in Denmark, stratified by socioeconomic group. To evaluate the effects of the ITFA ban (Danish Order no. 160 of March 2003) the Danish IMPACTSEC model was extended to quantify reductions in CHD deaths attributable to changes in ITFA (%E) intake between 1991-2007. Population counts were obtained from the Danish Central Office of Civil Registration, financial income from Statistics Denmark and ITFA intake from Dan-MONICA III (1991) and DANSDA (2005-2008). Participants were adults aged 25-84 years living in Denmark in 1991 and 2007, stratified by socioeconomic quintiles. The main outcome measure was CHD deaths prevented or postponed (DPP). Mean energy intake from ITFA was decimated between 1991 and 2007, falling from 1.1%E to 0.1%E in men and from 1·0%E to 0·1%E in women. Approximately 1,191 (95% CI 989-1,409) fewer CHD deaths were attributable to the ITFA reduction, representing some 11% of the overall 11,100 mortality fall observed in the period. The greatest attributable mortality falls were seen in the most deprived quintiles. Adding ITFA data to the original IMPACTsec model improved the overall model fit from 64% to 73%. In conclusion: Denmark's mandatory elimination of ITFA accounted for approximately 11% of the substantial reduction in CHD deaths observed between 1991 and 2007. The most deprived groups benefited the most, thus reducing inequalities. Adopting the Danish ITFA regulatory approach elsewhere could substantially reduce CHD mortality while improving health equity.

Cumulative dietary risk assessment of pesticides in food for the Danish population for the period 2012-2017.

The cumulative chronic dietary exposure for the Danish population were assessed using Danish food monitoring data for the period 2012-2017 and Danish food consumption data for the consumer groups children (age 1-2, age 4-6 and age 7-14 years), adults age 15-75, high consumers and consumers eating Danish produced fruit and vegetables whenever possible. Levels below the Limit of Reporting (LOR) were set to ½ LOR with correction. For risk assessment of the cumulative chronic dietary exposure we used the Hazard Index (HI) method where the Hazard Quotient (HQ) was calculated for each pesticide and summed up to a HI. The HI was calculated to be below 1 for all consumer groups; i.e. 0.36 for children age 4-6 years and 0.13 for adults, indicating that the cumulative chronic dietary pesticide exposure is unlikely to constitute a health risk for Danish consumers, even for high consumers eating 600 g or more of fruit and vegetables each day. By eating Danish produced commodities whenever possible, the HI was reduced by a factor of one third for both children and adults. 25 different commodities contributed to about 90% of the HI and to 84% of the exposure.

Improving the diet of employees at blue-collar worksites: results from the 'Food at Work' intervention study.

OBJECTIVE: To examine the impact of a 6-month participatory and empowerment-based intervention study on employees' dietary habits and on changes in the canteen nutrition environment. DESIGN: Worksites were stratified by company type and by the presence or absence of an in-house canteen, and randomly allocated to either an intervention group (five worksites) or a minimum intervention control group (three worksites). The study was carried out in partnership with a trade union and guided by an ecological framework targeting both individual and environment levels. Outcome measures included: (i) changes in employees' dietary habits derived from 4 d pre-coded food diaries of a group of employees at the worksites (paired-data structure); and (ii) the canteen nutrition environment as identified by aggregating chemical nutritional analysis of individual canteen lunches (different participants at baseline and at endpoint). SETTING: Eight blue-collar worksites (five of these with canteens). SUBJECTS: Employees. RESULTS: In the intervention group (n 102), several significant positive nutritional effects were observed among employees, including a median daily decrease in intake of fat (-2.2 %E, P = 0.002) and cake and sweets (-18 g/10 MJ, P = 0.002) and a median increase in intake of dietary fibre (3 g/10 MJ, P < 0.001) and fruit (55 g/d, P = 0.007 and 74 g/10 MJ, P = 0.009). With regard to the canteen nutrition environment, a significant reduction in the percentage of energy obtained from fat was found in the intervention group (median difference 11 %E, P < 0.001, n 144). CONCLUSIONS: The present study shows that moderate positive changes in dietary patterns can be achieved among employees in blue-collar worksites.

Relative validity of the pre-coded food diary used in the Danish National Survey of Diet and Physical Activity.

OBJECTIVE: To determine the relative validity of the pre-coded food diary applied in the Danish National Survey of Dietary Habits and Physical Activity. DESIGN: A cross-over study among seventy-two adults (aged 20 to 69 years) recording diet by means of a pre-coded food diary over 4 d and a 4 d weighed food record. Intakes of foods and drinks were estimated, and nutrient intakes were calculated. Means and medians of intake were compared, and cross-classification of individuals according to intake was performed. To assess agreement between the two methods, Pearson and Spearman's correlation coefficients and weighted kappa coefficients were calculated. SETTING: Validation study of the pre-coded food diary against a 4 d weighed food record. SUBJECTS: Seventy-two volunteer, healthy free-living adults (thirty-five males, thirty-seven females). RESULTS: Intakes of cereals and vegetables were higher, and intakes of fruit, coffee and tea were lower, in the weighed food record compared with the food diary. Intakes of nutrients were grossly the same in the two methods, except for protein, where a higher intake was recorded in the weighed record. In general, moderate agreement between the two methods was found. CONCLUSIONS: Participants were classified moderately correct according to food and nutrient intakes assessed in the pre-coded food diary; however values of absolute food intakes should be used and interpreted with caution. Improvement of the methods to estimate portion size may increase the accuracy of the dietary intake estimates.