Inga Thorsdottir

Birth weight and risk of type 2 diabetes: A systematic review

CONTEXT Low birth weight is implicated as a risk factor for type 2 diabetes. However, the strength, consistency, independence, and shape of the association have not been systematically examined. OBJECTIVE To conduct a quantitative systematic review examining published evidence on the association of birth weight and type 2 diabetes in adults. DATA SOURCES AND STUDY SELECTION Relevant studies published by June 2008 were identified through literature searches using EMBASE (from 1980), MEDLINE (from 1950), and Web of Science (from 1980), with a combination of text words and Medical Subject Headings. Studies with either quantitative or qualitative estimates of the association between birth weight and type 2 diabetes were included. DATA EXTRACTION Estimates of association (odds ratio [OR] per kilogram of increase in birth weight) were obtained from authors or from published reports in models that allowed the effects of adjustment (for body mass index and socioeconomic status) and the effects of exclusion (for macrosomia and maternal diabetes) to be examined. Estimates were pooled using random-effects models, allowing for the possibility that true associations differed between populations. DATA SYNTHESIS Of 327 reports identified, 31 were found to be relevant. Data were obtained from 30 of these reports (31 populations; 6090 diabetes cases; 152 084 individuals). Inverse birth weight-type 2 diabetes associations were observed in 23 populations (9 of which were statistically significant) and positive associations were found in 8 (2 of which were statistically significant). Appreciable heterogeneity between populations (I(2) = 66%; 95% confidence interval [CI], 51%-77%) was largely explained by positive associations in 2 native North American populations with high prevalences of maternal diabetes and in 1 other population of young adults. In the remaining 28 populations, the pooled OR of type 2 diabetes, adjusted for age and sex, was 0.75 (95% CI, 0.70-0.81) per kilogram. The shape of the birth weight-type 2 diabetes association was strongly graded, particularly at birth weights of 3 kg or less. Adjustment for current body mass index slightly strengthened the association (OR, 0.76 [95% CI, 0.70-0.82] before adjustment and 0.70 [95% CI, 0.65-0.76] after adjustment). Adjustment for socioeconomic status did not materially affect the association (OR, 0.77 [95% CI, 0.70-0.84] before adjustment and 0.78 [95% CI, 0.72-0.84] after adjustment). There was no strong evidence of publication or small study bias. CONCLUSION In most populations studied, birth weight was inversely related to type 2 diabetes risk.

Fruit and vegetable intake in a sample of 11-year-old children in 9 European countries: The pro children cross-sectional survey

Background/Aims: An adequate fruit and vegetable intake provides essential nutrients and nutritive compounds and is considered an important part of a healthy lifestyle. No simple instrument has been available for the assessment of fruit and vegetable intake as well as its determinants in school-aged children applicable in different European countries. Within the Pro Children Project, such an instrument has been developed. This paper describes the cross-sectional survey in 11-year-olds in 9 countries. Methods: The cross-sectional survey used nationally, and in 2 countries regionally, representative samples of schools and classes. The questionnaires, including a precoded 24-hour recall component and a food frequency part, were completed in the classroom. Data were treated using common syntax files for portion sizes and for merging of vegetable types into four subgroups. Results: The results show that the fruit and vegetable intake in amounts and choice were highly diverse in the 9 participating countries. Vegetable intake was in general lower than fruit intake, boys consumed less fruit and vegetables than girls did. The highest total intake according to the 24-hour recall was found in Austria and Portugal, the lowest in Spain and Iceland. Conclusion: The fruit and vegetable intake in 11-year-old children was in all countries far from reaching population goals and food-based dietary guidelines on national and international levels.

Obesity and the metabolic syndrome: role of different dietary macronutrient distribution patterns and specific nutritional components on weight loss and maintenance

Weight loss and subsequent body weight maintenance are difficult for obese individuals despite the wide variety of dietary regimens and approaches. A substantial body of scientific evidence has shown that by simply varying the macronutrient distribution and composition of dietary factors, weight losses of varying amounts, longer-term body weight maintenance periods, better appetite regulation, and changes in features of the metabolic syndrome can be achieved. At present, renewed efforts are underway to increase the protein content of weight-loss diets, simultaneously restrict fat consumption to no more than 30%, favor polyunsaturated fat, have carbohydrates account for between 40 and 50% of total energy intake, and promote the consumption of low-glycemic foods. The present article reviews the scientific evidence for the effects of several dietary manipulations and sustainable strategies for weight loss and body weight stability as well as for treating specific features of the metabolic syndrome.

Randomized trial of weight-loss-diets for young adults varying in fish and fish oil content

Objective:To investigate the effect of including seafood and fish oils, as part of an energy-restricted diet, on weight loss in young overweight adults.Design:Randomized controlled trial of energy-restricted diet varying in fish and fish oil content was followed for 8 weeks. Subjects were randomized to one of four groups: (1) control (sunflower oil capsules, no seafood); (2) lean fish (3 × 150 g portions of cod/week); (3) fatty fish (3 × 150 g portions of salmon/week); (4) fish oil (DHA/EPA capsules, no seafood). The macronutrient composition of the diets was similar between the groups and the capsule groups, were single-blinded.Subjects:A total of 324 men and women aged 20–40 years, BMI 27.5–32.5 kg/m2 from Iceland, Spain and Ireland.Measurements:Anthropometric data were collected at baseline, midpoint and endpoint. Confounding factors were accounted for, with linear models, for repeated measures with two-way interactions. The most important interactions for weight loss were (diet × energy intake), (gender × diet) and (gender × initial-weight).Results:An average man in the study (95 kg at baseline receiving 1600 kcal/day) was estimated to lose 3.55 kg (95% CI, 3.14–3.97) (1); 4.35 kg (95% CI, 3.94–4.75) (2); 4.50 kg (95% CI, 4.13–4.87) (3) and 4.96 kg (95% CI, 4.53–5.40) on diet (4) in 4 weeks, from baseline to midpoint. The weight-loss from midpoint to endpoint was 0.45 (0.41–0.49) times the observed weight loss from baseline to midpoint. The diets did not differ in their effect on weight loss in women. Changes in measures of body composition were in line with changes in body weight.Conclusion:In young, overweight men, the inclusion of either lean or fatty fish, or fish oil as part of an energy-restricted diet resulted in ∼1 kg more weight loss after 4 weeks, than did a similar diet without seafood or supplement of marine origin. The addition of seafood to a nutritionally balanced energy-restricted diet may boost weight loss.

Patterns in sedentary and exercise behaviors and associations with overweight in 9–14-year-old boys and girls - a cross-sectional study.

BackgroundBefore starting interventions addressing energy-balance related behaviors, knowledge is needed about the prevalence of sedentary behaviors and low physical exercise, their interrelationships, possible gender differences. Therefore this study aimed to describe gender differences in sedentary and physical exercise behaviors and their association with overweight status in children from nine European countries. Additionally, to identify clusters of children sharing the same pattern regarding sedentary and physical exercise behavior and compare these groups regarding overweight status.MethodsCross-sectional study among 11-year-old children in nine countries (n = 12538). Self-administered questionnaires assessed the time spent on TV viewing during dinner and during the day, PC use and on physical exercise. The parents reported childrens weight and height. Descriptive statistics, cluster analyses, and logistic regression analyses were used for data analyses.ResultsBoys spent more time on sedentary behaviors but also more on physical exercise than girls. High TV viewing and low exercise behavior independently increased the risk of being overweight. Based on the behaviors, five clusters were identified. Among boys, clear associations with being overweight were found, with the most unhealthy behavior pattern having the highest risks of being overweight. Among girls, high TV viewers and high PC users had increased risk of being overweight. In girls sedentary behaviors seemed more important than physical exercise with regard to overweight status.ConclusionDespite selective non-response on BMI and reliance on self-reports, the associations between clusters and overweight in boys were clear, and differences between boys and girls regarding the behaviors and risks for overweight are noteworthy. These differences need to be considered when developing tailored intervention strategies for prevention of overweight.

Promoting Fruit and Vegetable Consumption among European Schoolchildren: Rationale, Conceptualization and Design of the Pro Children Project

Background/Aims: The Pro Children Project was designed to assess fruit and vegetable consumption in European schoolchildren and their parents, as well as determinants of the children’s consumption patterns. A second objective was to develop and test strategies, applicable across Europe, for promoting consumption of fruits and vegetables among schoolchildren and their parents. In this paper, the rationale, theoretical background, overall design and implementation of the project is presented. Methods: Surveys of national, representative samples of 11-year-old schoolchildren and their parents were conducted in 9 countries, i.e. in Austria, Belgium, Denmark, Iceland, the Netherlands, Norway, Portugal, Spain and Sweden. Comprehensive school-based educational programmes have been developed and tested in three settings, i.e. in Spain, the Netherlands and in Norway. A precoded 24-hour recall form combined with a set of food frequency questions assessing regular intake were used to assess fruit and vegetable consumption. Determinants were assessed employing a comprehensive theoretical framework including personal, social and environmental factors related to fruit and vegetable consumption. The intervention programmes have been tested employing a group-randomized trial design where schools have been randomly allocated to an intervention arm and a delayed intervention arm. Surveys among all participating children and their parents were conducted prior to the initiation of the intervention, immediately after the end of the intervention and at the end of the subsequent school year. Conclusion: The project is expected to provide new information of great importance for improving our understanding of consumption patterns of fruits and vegetables and for guiding future efforts to promote increased consumption patterns across Europe.

Effects of an isocaloric healthy Nordic diet on insulin sensitivity, lipid profile and inflammation markers in metabolic syndrome – a randomized study (SYSDIET)

Different healthy food patterns may modify cardiometabolic risk. We investigated the effects of an isocaloric healthy Nordic diet on insulin sensitivity, lipid profile, blood pressure and inflammatory markers in people with metabolic syndrome.

Maternal diet in early and late pregnancy in relation to weight gain

Objective:To identify dietary factors related to the risk of gaining weight outside recommendations for pregnancy weight gain and birth outcome.Design:An observational study with free-living conditions.Subjects:Four hundred and ninety five healthy pregnant Icelandic women.Methods:The dietary intake of the women was estimated with a semiquantitative food frequency questionnaire covering food intake together with lifestyle factors for the previous 3 months. Questionnaires were filled out at between 11 and 15 weeks and between 34 and 37 weeks gestation. Comparison of birth outcome between the three weight gain groups was made with ANOVA and Bonferroni post hoc tests. Dietary factors related to at least optimal and excessive weight gain during pregnancy were represented with logistic regression controlling for potential confounding.Results:Of the women, 26% gained suboptimal and 34% excessive weight during pregnancy. Women in late pregnancy with at least optimal, compared with women with suboptimal, weight gain were eating more (OR=3.32, confidence interval (CI)=1.81–6.09, P<0.001) and drinking more milk (OR=3.10, CI=1.57–6.13, P=0.001). The same dietary factors were related to excessive, compared with optimal, weight gain. Furthermore, eating more sweets early in pregnancy increased the risk of gaining excessive weight (OR=2.52, CI=1.10–5.77, P=0.029). Women with a body mass index of 25.0–29.9 kg/m2 before pregnancy were most likely to gain excessive weight (OR=7.37, CI 4.13–13.14, P<0.001). Women gaining suboptimal weight gave birth to lighter children (P<0.001) and had shorter gestation (P=0.008) than women gaining optimal or excessive weight.Conclusion:Women who are overweight before pregnancy should get special attention regarding lifestyle modifications affecting consequent weight gain during pregnancy. They are most likely to gain excessive weight and therefore most likely to suffer pregnancy and delivery complications and struggle with increasing overweight and obesity after giving birth.

A diet rich in long chain omega-3 fatty acids modulates satiety in overweight and obese volunteers during weight loss.

Long chain omega-3 fatty acids (LC n-3 FA) are considered nutritional factors with a potential to modulate food intake. Thus, the aim of the current study was to determine whether appetite could be affected by LC n-3 FA when included in a calorie-restricted diet to treat overweight or obesity. Appetite was explored in volunteers (31+/-5 years; BMI: 28.3+/-1.5 kg/m(2)) during the last 2 weeks of an 8-week energy-restricted balanced diet (weight loss=-5.9+/-3.1%) providing either a low (<260 mg/day; n=112) or a high amount (>1300 mg/day; n=121) of LC n-3 FA. Erythrocyte membrane fatty acids were measured to detect diet-related changes in fatty acids and a validated visual analogue scale (VAS) was used to measure hunger sensations directly after and 2h after a test dinner. The LC n-3 FA content in erythrocyte membrane was lower in the low LC n-3 FA group (10.5+/-2.5% vs. 12.5+/-2.6%; p<0.001) after the intervention. The VAS assessment revealed lower hunger sensations in the high LC n-3 FA group immediately after the test dinner (fullness: p=0.045) and after 120 min (fullness: p=0.008; hunger: p=0.039). Correlation analysis showed a positive relation between n-3 FA/n-6 FA ratio in erythrocyte membrane and fullness 2h postprandial (r=0.139; p=0.032). In conclusion, LC n-3 FA intake modulates postprandial satiety in overweight and obese volunteers during weight loss. Further research is needed to investigate whether LC n-3 FA improve compliance to the nutritional treatment of overweight and obesity as well as weight loss maintenance.

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.