Lene Frost Andersen

Health benefits of nuts : potential role of antioxidants

A diet rich in fruits, vegetables and minimally refined cereals is associated with lower risk for chronic degenerative diseases. Since oxidative stress is common in chronic degenerative disease, it has been assumed that dietary antioxidants may explain this protective effect. Every dietary plant contains numerous types of antioxidants with different properties. Many of these antioxidants cooperate in oxidative stress reduction in plants, and we hypothesize that many different antioxidants may also be needed for the proper protection of animal cells. To test this hypothesis, it is useful to identify dietary plants with high total antioxidant content. Several nuts are among the dietary plants with the highest content of total antioxidants. Of the tree nuts, walnuts, pecans and chestnuts have the highest contents of antioxidants. Walnuts contain more than 20 mmol antioxidants per 100 g, mostly in the walnut pellicles. Peanuts (a legume) also contribute significantly to dietary intake of antioxidants. These data are in accordance with our present extended analysis of an earlier report on nut intake and death attributed to various diseases in the Iowa Womens Health Study. We observed that the hazard ratio for total death rates showed a U-shaped association with nut/peanut butter consumption. Hazard ratio was 0.89 (CI = 0.81-0.97) and 0.81 (CI = 0.75-0.88) for nut/peanut butter intake once per week and 1-4 times per week, respectively. Death attributed to cardiovascular and coronary heart diseases showed strong and consistent reductions with increasing nut/peanut butter consumption. Further studies are needed to clarify whether antioxidants contribute to this apparent beneficial health effect of nuts.

Infant feeding practices and associated factors in the first six months of life: the Norwegian infant nutrition survey.

Aim: To describe and evaluate infant feeding practices during the first 6 mo of life in relation to recommendations, and to study infant feeding practices in relation to maternal and infant characteristics. Methods: Data from 2383 Norwegian infants aged 6 mo were collected by a self‐administered semi‐quantitative food‐frequency questionnaire measuring feeding practices at 6 mo and feeding practices retrospectively at ≤5.5 mo of age. Results: Only 1% of the infants had never been breastfed. The proportion of breastfed infants was 96% at 1 mo, 85% at 4 mo and 80% at 6 mo. The proportion of exclusively breastfed infants was 90% at 1 mo, 44% at 4 mo and 7% at 6 mo. Twenty‐one percent of the infants were introduced to solid foods before the age of 4 mo. For exclusive breastfeeding at 4 mo, breastfeeding at 6 mo and timely introduction of solid foods (not before 4 mo) significant positive trends were found for maternal age, education and degree of urbanization. Negative associations were found for maternal smoking. Furthermore, exclusive breastfeeding at 4 mo was associated with infant gender and marital status, and the odds of breastfeeding at 6 mo significantly decreased with decreasing infant birthweight. Finally, both the odds of exclusive breastfeeding at 4 mo and of breastfeeding at 6 mo increased with increasing numbers of children.

Overweight and obesity among Norwegian schoolchildren: Changes from 1993 to 2000

Aim: The aim of the present study was to investigate the prevalence rate of overweight and obesity in a nationwide survey of fourth- and eighth-grade Norwegian schoolchildren, the changes in overweight rates among eighth graders from 1993 to 2000, and to investigate factors associated with overweight. Methods: Cross-sectional dietary surveys were conducted on nationally representative samples of eighth graders in 1993, and among fourth and eighth graders in 2000. Self-reported weight and height was available from 1,650 eighth graders in 1993, and from 664 fourth and 825 eighth graders in 2000. Data on dietary pattern, social class, and physical activity were also available. Results: In 2000 the prevalence of overweight and obesity among the fourth graders was 18.5% and 3.6%, respectively, and among the eighth graders 11.5% and 1.8%, respectively. A marked increase in overweight and obesity among Norwegian eighth graders from 1993 to 2000 was observed; the prevalence of overweight and obesity increased by 4 and 0.9 percentage points, respectively. Social class, time spent watching TV or in front of a computer, and breakfast frequency were associated with the odds of being overweight. An inverse relation between intake of sweets and overweight was observed. Validation studies demonstrated a high correlation between self-reported and measured height and weight in both age groups. Conclusion: The present study demonstrates a high prevalence of overweight and obesity among schoolchildren, especially among fourth graders in Norway. Moreover, the proportion of overweight and obese children has increased greatly among eighth graders during the last decade.

Estimating Usual Food Intake Distributions by Using the Multiple Source Method in the EPIC-Potsdam Calibration Study

Estimating usual food intake distributions from short-term quantitative measurements is critical when occasionally or rarely eaten food groups are considered. To overcome this challenge by statistical modeling, the Multiple Source Method (MSM) was developed in 2006. The MSM provides usual food intake distributions from individual short-term estimates by combining the probability and the amount of consumption with incorporation of covariates into the modeling part. Habitual consumption frequency information may be used in 2 ways: first, to distinguish true nonconsumers from occasional nonconsumers in short-term measurements and second, as a covariate in the statistical model. The MSM is therefore able to calculate estimates for occasional nonconsumers. External information on the proportion of nonconsumers of a food can also be handled by the MSM. As a proof-of-concept, we applied the MSM to a data set from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam Calibration Study (2004) comprising 393 participants who completed two 24-h dietary recalls and one FFQ. Usual intake distributions were estimated for 38 food groups with a proportion of nonconsumers > 70% in the 24-h dietary recalls. The intake estimates derived by the MSM corresponded with the observed values such as the group mean. This study shows that the MSM is a useful and applicable statistical technique to estimate usual food intake distributions, if at least 2 repeated measurements per participant are available, even for food groups with a sizeable percentage of nonconsumers.

Current micronutrient recommendations in Europe: towards understanding their differences and similarities

BackgroundNowadays most countries in Europe have established their own nutrient recommendations to assess the adequacy of dietary intakes and to plan desirable dietary intakes. As yet there is no standard approach for deriving nutrient recommendations, they may vary from country to country. This results in different national recommendations causing confusion for policy-makers, health professionals, industry, and consumers within Europe. EURRECA (EURopean micronutrient RECommendations Aligned) is a network of excellence funded by the European Commission (EC), and established to identify and address the problem of differences between countries in micronutrient recommendations. The objective of this paper is to give an overview of the available micronutrient recommendations in Europe, and to provide information on their origin, concepts and definitions. Furthermore this paper aims to illustrate the diversity in European recommendations on vitamin A and vitamin D, and to explore differences and commonalities in approaches that could possibly explain variations observed.MethodsA questionnaire was developed to get information on the process of establishing micronutrient recommendations. These questionnaires were sent to key informants in the field of micronutrient recommendations to cover all European countries/regions. Also the latest reports on nutrient recommendations in Europe were collected. Standardisation procedures were defined to enable comparison of the recommendations. Recommendations for vitamin A and vitamin D were compared per sex at the ages 3, 9 months and 5, 10, 15, 25, 50 and 70 years. Information extracted from the questionnaires and reports was compared focusing on: (1) The concept of recommendation (recommended daily allowance (RDA), adequate intake (AI) or acceptable range), (2) The year of publication of the report (proxy for available evidence), (3) Population groups defined, (4) Other methodological issues such as selected criteria of adequacy, the type of evidence used, and assumptions made.ResultsTwenty-two countries, the World Health Organization (WHO)/the Food and Agriculture Organization of the United Nations (FAO) and the EC have their own reports on nutrient recommendations. Thirteen countries based their micronutrient recommendations on those from other countries or organisations. Five countries, WHO/FAO and the EC defined their own recommendations. The DACH-countries (Germany, Austria and Switzerland) as well as the Nordic countries (Norway, Sweden, Finland, Denmark and Iceland) cooperated in setting recommendations. Greece and Portugal use the EC and the WHO/FAO recommendations, respectively and Slovenia adopted the recommendations from the DACH-countries. Rather than by concepts, definitions, and defined population groups, variability appears to emerge from differences in criteria for adequacy, assumptions made and type of evidence used to establish micronutrient recommendations.DiscussionThe large variation in current micronutrient recommendations for population groups as illustrated for vitamin A and vitamin D strengthens the need for guidance on setting evidence based, up-to-date European recommendations. Differences in endpoints, type of evidence used to set recommendations, experts’ opinions and assumptions are all likely to contribute to the identified variation. So far, background information was not sufficient transparent to disentangle the relative contribution of these different aspects.ConclusionEURRECA has an excellent opportunity to develop tools to improve transparency on the approaches used in setting micronutrient recommendations, including the selection of criteria for adequacy, weighing of evidence, and interpretation of data.

Validity and Reproducibility of a Precoded Questionnaire to Assess Fruit and Vegetable Intake in European 11- to 12-Year-Old Schoolchildren

Background/Aims: Validity and reproducibility were evaluated of a new questionnaire to assess fruit and vegetable intakes in 11- to 12-year-old children. Methods: The precoded teacher-assisted self-administered questionnaire included two sections: a 24-hour recall part and a food frequency part. Validity was tested in 4 countries (Denmark, Iceland, Norway, Portugal; n = 43–60 per country) using a 1-day weighed food record and 7-day food records as reference methods. Test-retest (7–12 days apart) reproducibility was assessed in 6 countries (Belgium, Denmark, Iceland, Norway, Portugal, Spain; n = 60–74 per country). Results: Spearman rank correlations for fruit and vegetable intake according to the frequency part and the 7-day food record ranged between r = 0.40–0.53. Between 25–50% were classified into the same quartile and 70–88% into the same or adjacent quartile. Test-retest Spearman rank correlations for the food frequency part were r = 0.47–0.84. Three countries showed no significant difference between fruit intake as assessed with the 24-hour recall part and the 1-day weighed food record, and 2 countries showed no significant difference for vegetables. In the other countries, the 24-hour recall part resulted in substantially higher mean intake levels. Conclusion: Validity and reproducibility as to ranking of subjects were regarded to be satisfactory in all countries. Group mean intake, based on the original 24-hour part, was valid for fruit in 3 countries and for vegetables in 2 countries, and this part was subsequently adjusted to avoid overestimation, before the questionnaire was used in the Pro Children study.

The stability of soft drinks intake from adolescence to adult age and the association between long-term consumption of soft drinks and lifestyle factors and body weight.

OBJECTIVES To investigate the tracking of sugar-sweetened, carbonated soft drinks intake from age 15 to 33 years and the association between this intake and lifestyle factors and body weight. DESIGN A longitudinal study with 18-20 years of follow-up. Data about diet, physical activity, smoking and dieting were collected in 1981/1979, 1991 and 1999. Body weight and height were measured in 1981/1979 and self-reported in 1999. SETTING Oslo, Norway. SUBJECTS Four hundred and twenty-two men and women. RESULTS Tracking of soft drinks intake from adolescence into early adulthood (age 25 years) and from early adulthood into later adulthood (33 years) was moderate to high, while tracking from adolescence into later adulthood was low. Comparing those reporting a high intake of soft drinks in both 1991 and 1999 with those reporting a low intake at both times, male long-term high consumers were more likely to smoke (48 vs. 21%, P=0.002) and reported higher intakes of energy (12.2 vs. 10.2 MJ day(-1), P=0.005) and sugar (142 vs. 50 g day(-1), P<0.001) in 1999 than did long-term low consumers. Women high consumers were less likely to be physically active (14 vs. 42%, P=0.03) and had higher sugar intake (87 vs. 41 g day(-1), P<0.001) in 1999 than did women low consumers. There were no differences in body mass index, overweight or obesity in 1999 between long-term high and low consumers. CONCLUSION In this study, stability of soft drinks intake from age 15 to 25 years and from age 25 to 33 years was moderate to high, while from age 15 to 33 years it was low. Soft drinks intake from age 25 to 33 years was associated with smoking and physical inactivity, but not with body weight.

Maternal recall of breastfeeding duration twenty years after delivery

BackgroundStudies on the health benefits from breastfeeding often rely on maternal recall of breastfeeding. Although short-term maternal recall has been found to be quite accurate, less is known about long-term accuracy. The objective of this study was to assess the accuracy of long-term maternal recall of breastfeeding duration.MethodsIn a prospective study of pregnancy and birth outcome, detailed information on breastfeeding during the child’s first year of life was collected from a cohort of Norwegian women who gave birth in 1986–88. Among 374 of the participants, data on breastfeeding initiation and duration were compared to recalled data obtained from mailed questionnaires some 20 years later. Intraclass correlation coefficient (ICC), Bland-Altman plot, and Kappa statistics were used to assess the agreement between the two sources of data. Logistic regression was used to assess predictors of misreporting breastfeeding duration by more than one month.ResultsRecorded and recalled breastfeeding duration were strongly correlated (ICC=0.82, p < 0.001). Nearly two thirds of women recalled their breastfeeding to within one month. Recall data showed a modest median overestimation of about 2 weeks. There were no apparent systematic discrepancies between the two sources of information, but recall error was predicted by the age when infants were introduced to another kind of milk. Across categories of breastfeeding, the overall weighted Kappa statistic showed an almost perfect agreement (κ = 0.85, 95% confidence interval [CI] 0.82 – 0.88).ConclusionBreastfeeding duration was recalled quite accurately 20 years after mothers gave birth in a population where breastfeeding is common and its duration long.

Evaluation of the odd fatty acids 15:0 and 17:0 in serum and adipose tissue as markers of intake of milk and dairy fat.

Background:There is a need for biomarkers of dietary saturated fatty acids, because several diseases have been related to intake of these fatty acids.Objective:To examine the relation between intake of dairy fat and the proportion of pentadecanoic (15:0) and heptadecanoic (17:0) acid in serum and adipose tissue.Design:Healthy men aged 21–55 y provided serum (n=110) and adipose tissue samples (n=107) and completed both 14 days weighed records (WR) and a 180-item food frequency questionnaire (FFQ). The proportions of 15:0 and 17:0 acid in serum and adipose tissue as measured by gas liquid chromatography were evaluated as biomarkers for fat intake from dairy products using Pearsons correlation coefficient and the method of triads.Results:The strongest correlation coefficients were observed between total intake of dairy fat estimated from WR and relative content of 15:0 in adipose tissue (0.52, 95% CI: 0.37, 0.65) and total serum (0.43, 95% CI 0.26, 0.57). A consistent inverse association was observed between the intake of milk fat and relative serum content of 17:0. The validity coefficients observed for the intake of dairy fat estimated from weighed records, the 180-item FFQ and by the relative content of 15:0 in serum and adipose tissue were 0.94 (95% CI: 0.68, 1.00), 0.50 (95% CI: 0.29, 0.67), 0.49 (95% CI: 0.32, 0.67) and 0.56 (95% CI: 0.28, 0.82), respectively.Conclusion:Relative content of 15:0 in serum and adipose tissue may be a useful biomarker for the intake of total dairy fat, whereas FFQs and WRs may provide better estimates of the intake of fat from milk.

Comparison of diet measures from a food-frequency questionnaire with measures from repeated 24-hour dietary recalls. The Norwegian Women and Cancer Study.

OBJECTIVE To compare diet measures from a food-frequency questionnaire (FFQ) with measures from 24-hour dietary recalls (24HDRs). DESIGN The participants answered an FFQ after completing four, repeated 24HDRs during a year. SETTING Norway, nationwide. SUBJECTS Of 500 women randomly selected from The Norwegian Women and Cancer Study (the Norwegian arm of the European Prospective Investigation into Cancer and Nutrition), 286 agreed to participate and 238 completed the study. RESULTS On the group level, the FFQ overestimated absolute intake in seven and underestimated intake in six of 21 food groups. Intakes of energy, fat, added sugar and alcohol were lower in the FFQ than in the 24HDRs, whereas intake of fibre was higher. Spearmans rank correlation coefficient ranged from 0.13 (desserts) to 0.82 (coffee) for foods, and from 0.25 (beta-carotene) to 0.67 (alcohol) for nutrients. Three per cent of the observations on nutrient intake fell in the opposite quintile when classified according to the FFQ as compared with the 24HDR. The median calibration coefficient, calculated by regression of the 24HDR data on the FFQ data, was 0.57 for foods and 0.38 for nutrients. CONCLUSIONS The FFQs ability to rank subjects was good for foods eaten frequently and fairly good for macronutrients in terms of energy percentages. Weaker ranking abilities were seen for foods eaten infrequently and for some micronutrients. The results underline the necessity of performing measurement error corrections.