Manfred J. Müller

Critical review: vegetables and fruit in the prevention of chronic diseases

BackgroundVegetables and fruit provide a significant part of human nutrition, as they are important sources of nutrients, dietary fibre, and phytochemicals. However, it is uncertain whether the risk of certain chronic diseases can be reduced by increased consumption of vegetables or fruit by the general public, and what strength of evidence has to be allocated to such an association.MethodsTherefore, a comprehensive analysis of the studies available in the literature and the respective study results has been performed and evaluated regarding obesity, type 2 diabetes mellitus, hypertension, coronary heart disease (CHD), stroke, cancer, chronic inflammatory bowel disease (IBD), rheumatoid arthritis (RA), chronic obstructive pulmonary disease (COPD), asthma, osteoporosis, eye diseases, and dementia. For judgement, the strength of evidence for a risk association, the level of evidence, and the number of studies were considered, the quality of the studies and their estimated relevance based on study design and size.ResultsFor hypertension, CHD, and stroke, there is convincing evidence that increasing the consumption of vegetables and fruit reduces the risk of disease. There is probable evidence that the risk of cancer in general is inversely associated with the consumption of vegetables and fruit. In addition, there is possible evidence that an increased consumption of vegetables and fruit may prevent body weight gain. As overweight is the most important risk factor for type 2 diabetes mellitus, an increased consumption of vegetables and fruit therefore might indirectly reduces the incidence of type 2 diabetes mellitus. Independent of overweight, there is probable evidence that there is no influence of increased consumption on the risk of type 2 diabetes mellitus. There is possible evidence that increasing the consumption of vegetables and fruit lowers the risk of certain eye diseases, dementia and the risk of osteoporosis. Likewise, current data on asthma, COPD, and RA indicate that an increase in vegetable and fruit consumption may contribute to the prevention of these diseases. For IBD, glaucoma, and diabetic retinopathy, there was insufficient evidence regarding an association with the consumption of vegetables and fruit.ConclusionsThis critical review on the associations between the intake of vegetables and fruit and the risk of several chronic diseases shows that a high daily intake of these foods promotes health. Therefore, from a scientific point of view, national campaigns to increase vegetable and fruit consumption are justified. The promotion of vegetable and fruit consumption by nutrition and health policies is a preferable strategy to decrease the burden of several chronic diseases in Western societies.

ESPEN guidelines for nutrition in liver disease and transplantation

clinical stage of chronic liver disease: When diagnosed by anthropometric criteria, PEM may be present in 20% of patients with well compensated liver cirrhosis and in more than 60% of patients with severe liver insufficiency (5). The prevalence is even higher when body composition is assessed by more sensitive methods (4, 6). The presence of muscle wasting indicates an advanced stage and apparently is associated with poorer survival (7) particularly following shunt surgery (8). The prevalence and degree of PEM do not appear to relate to the etiology of liver disease per se (4, 5). The higher prevalence of malnutrition in patients with alcoholic liver disease is generally restricted to skid row alcoholics and patients from low socioeconomic classes.

Body fluid volume determination via body composition spectroscopy in health and disease

The assessment of extra-, intracellular and total body water (ECW, ICW, TBW) is important in many clinical situations. Bioimpedance spectroscopy (BIS) has advantages over dilution methods in terms of usability and reproducibility, but a careful analysis reveals systematic deviations in extremes of body composition and morbid states. Recent publications stress the need to set up and validate BIS equations in a wide variety of healthy subjects and patients with fluid imbalance. This paper presents two new equations for determination of ECW and ICW (referred to as body composition spectroscopy, BCS) based on Hanai mixture theory but corrected for body mass index (BMI). The equations were set up by means of cross validation using data of 152 subjects (120 healthy subjects, 32 dialysis patients) from three different centers. Validation was performed against bromide/deuterium dilution (NaBr, D2O) for ECW/TBW and total body potassium (TBK) for ICW. Agreement between BCS and the references (all subjects) was -0.4 +/- 1.4 L (mean +/- SD) for ECW, 0.2 +/- 2.0 L for ICW and -0.2 +/- 2.3 L for TBW. The ECW agreement between three independent reference methods (NaBr versus D2O-TBK) was -0.1 +/- 1.8 L for 74 subjects from two centers. Comparing the new BCS equations with the standard Hanai approach revealed an improvement in SEE for ICW and TBW by 0.6 L (24%) for all subjects, and by 1.2 L (48%) for 24 subjects with extreme BMIs (<20 and >30). BCS may be an appropriate method for body fluid volume determination over a wide range of body compositions in different states of health and disease.

Parental overweight, socioeconomic status and high birth weight are the major determinants of overweight and obesity in 5–7 y-old children: baseline data of the Kiel Obesity Prevention Study (KOPS)

OBJECTIVES: To identify the major risk factors of overweight and obesity in prepubertal children.DESIGN: Cross-sectional study.SETTING: In all, 32 primary schools in Kiel (248 000 inhabitants), northwest Germany.SUBJECTS: A total of 2631 5–7-y-old German children and their parents.MAIN OUTCOME MEASURES: Weight status, socio-economic status (SES), parental overweight, dietary intake, activity, inactivity and further determinants (birth weight, breast feeding, nutritional status of siblings) of the children.RESULTS: The prevalence of overweight (≥90th BMI percentile of reference) was 9.2% in boys and 11.2% in girls, respectively. Considered univariately, family-, environment- and development-related determinants showed some relations to overweight and obesity. In multivariate analyses parental overweight, a low SES as well as a high birth weight were the strongest independent risk factors of overweight and obesity in children. Additionally, there were sex-specific risk factors: parental smoking and single households were risk factors in boys, whereas a low activity was associated with obesity in girls. Birth weight was associated with obesity, but not with overweight. The prevalence of obesity reached 29.2% in boys and 33.4% in girls with all the three main risk factors.CONCLUSIONS: Overweight families of low SES have the highest risk of overweight and obese children. Future prevention programmes must also take into account sex-specific risk factors.

Vitamin D status and health correlates among German adults

Objective:To analyze vitamin D status based on serum 25-hydroxyvitamin D (25OHD) measurements, its determinants and health correlates in a representative sample of German adults.Subjects:A total of 1763 men and 2267 women, 18- to 79-year old, who participated in the representative German National Health Interview and Examination Survey 1998 and the integrated German Nutrition Survey.Results:The median vitamin D intake from both diet and supplements did not meet the recommended level of 5 μg/day, in either men (2.8 μg/day) or women (2.3 μg/day). Altogether 80.9% of men and 88.5% of women had vitamin D intakes below this level. Moderate (12.5–25 nmol/l serum 25OHD levels) and mild (25–50 nmol/l) vitamin D deficiency was prevalent in the adult population in Germany, even in younger age groups. Overall, 57% of men and 58% of women had vitamin D levels below 50 nmol/l. Among 65- to 79-year-old women, the proportion amounted to 75%, even during the sunnier half of the year. In sex-specific multiple linear regression models, independent determinants of serum 25OHD levels consistently included season, vitamin D intake from both diet and supplements, physical activity and living in a partnership. In addition, age and current menopausal hormone use contributed to the model among women, as opposed to time of day of blood sampling and body mass index (marginally) among men. Significantly lower serum 25OHD levels were observed in women with hypertension, cardiovascular diseases and noninsulin-treated diabetes mellitus as well as in men with insulin-treated diabetes mellitus compared with nonaffected participants.Conclusions:Vitamin D deficiency is a public health issue in Germany. We identified a number of determinants with potential for primary prevention of vitamin D deficiency. Risk and benefits of preventive actions need to be examined in further studies.

Quercetin reduces systolic blood pressure and plasma oxidised low-density lipoprotein concentrations in overweight subjects with a high-cardiovascular disease risk phenotype: a double-blinded, placebo-controlled cross-over study

Regular consumption of flavonoids may reduce the risk for CVD. However, the effects of individual flavonoids, for example, quercetin, remain unclear. The present study was undertaken to examine the effects of quercetin supplementation on blood pressure, lipid metabolism, markers of oxidative stress, inflammation, and body composition in an at-risk population of ninety-three overweight or obese subjects aged 25-65 years with metabolic syndrome traits. Subjects were randomised to receive 150 mg quercetin/d in a double-blinded, placebo-controlled cross-over trial with 6-week treatment periods separated by a 5-week washout period. Mean fasting plasma quercetin concentrations increased from 71 to 269 nmol/l (P < 0.001) during quercetin treatment. In contrast to placebo, quercetin decreased systolic blood pressure (SBP) by 2.6 mmHg (P < 0.01) in the entire study group, by 2.9 mmHg (P < 0.01) in the subgroup of hypertensive subjects and by 3.7 mmHg (P < 0.001) in the subgroup of younger adults aged 25-50 years. Quercetin decreased serum HDL-cholesterol concentrations (P < 0.001), while total cholesterol, TAG and the LDL:HDL-cholesterol and TAG:HDL-cholesterol ratios were unaltered. Quercetin significantly decreased plasma concentrations of atherogenic oxidised LDL, but did not affect TNF-alpha and C-reactive protein when compared with placebo. Quercetin supplementation had no effects on nutritional status. Blood parameters of liver and kidney function, haematology and serum electrolytes did not reveal any adverse effects of quercetin. In conclusion, quercetin reduced SBP and plasma oxidised LDL concentrations in overweight subjects with a high-CVD risk phenotype. Our findings provide further evidence that quercetin may provide protection against CVD.

Incidence and prognostic value of malnutrition and wasting in human immunodeficiency virus-infected outpatients

Although malnutrition and wasting are known features of human immunodeficiency virus (HIV) infection, their incidence and possible association with immunologic impairment are largely unknown, as is the prognostic value of the nutritional state. Nutritional, clinical, and immunologic parameters were measured in 100 outpatients in different stages of HIV infection. In addition, 39 patients with AIDS were prospectively followed for a mean period of 343 (range, 53-650) days. Sixty-three percent of the patients showed evidence of malnutrition, 21% suffered from wasting. A reduced body cell mass and decreased serum albumin levels were observed in 32 and 14%, respectively, predominantly in more advanced disease stages. Fourteen of 39 AIDS patients died after a mean survival of 212 days. Survivors showed significantly larger initial body cell mass values and higher initial serum albumin levels compared with nonsurvivors, whereas CD4+ lymphocyte counts, disease complications, and medication were all similar in both groups. Kaplan-Meier analyses revealed a significantly prolonged survival in patients with a body cell mass > 30% of body weight or serum albumin levels exceeding 30 g/L. Factor analyses indicated that the parameters of nutritional state were independent from each other and from CD4+ lymphocyte counts. Malnutrition occurs frequently during HIV infection and increases with disease progress. It strongly predicts patient survival independent of CD4+ lymphocyte counts.

Value of body fat mass vs anthropometric obesity indices in the assessment of metabolic risk factors

Objective:To compare the value of body fat mass (%FM) to indirect measures of general (body mass index (BMI)) and central adiposity (waist circumference (WC); waist-to-height ratio (WC/ht)) for the prediction of overweight- and obesity-related metabolic risk in a study population with a high prevalence of metabolic syndrome (MSX).Methods:BMI, WC, WC/ht, body composition (by air-displacement plethysmography) and metabolic risk factors: triglycerides, cholesterol, HDL-cholesterol (HDL-C), uric acid, systolic blood pressure (BPsys), insulin resistance by homeostasis model assessment (HOMA-IR) and C-reactive protein (CRP) were measured in 335 adults (191 women, 144 men; mean age 53 ±13.9 years, prevalence of MSX 30%).Results:When compared with BMI and WC, %FM showed weaker associations with metabolic risk factors, except for CRP and BPsys in men. In women, HDL-C and HOMA-IR showed the closest correlations with BMI. For all other risk factors, WC or WC/ht were the best predictors in both sexes. Differences in the strength of correlations between an obesity index and different risk factors exceeded the differences observed between all obesity indices within one risk factor. In stepwise multiple regression analyses, WC/ht was the main predictor of metabolic risk in both sexes combined. However, analysis of the area under receiver operating characteristic curves for prediction of the prevalence of ⩾2 component traits of the MSX revealed a similar accuracy of all obesity indices.Conclusions:At the population level, measurement of body FM has no advantage over BMI and WC in the prediction of obesity-related metabolic risk. Although measures of central adiposity (WC, WC/ht) tended to show closer associations with risk factors than measures of general adiposity, the differences were small and depended on the type of risk factor and sex, suggesting an equivalent value of methods.

Prevention of obesity--more than an intention. Concept and first results of the Kiel Obesity Prevention Study (KOPS).

OBJECTIVE: Obesity prevention is necessary to address the steady rise in the prevalence of obesity. Although all experts agree that obesity prevention has high priority there is almost no research in this area. The effectiveness of different intervention strategies is not well documented. There is also no structured framework for obesity prevention.DESIGN: Based on (i) our current and limited knowledge and (ii) the idea that prevention of childhood obesity is an effective treatment of adult obesity, the Kiel Obesity Prevention Study (KOPS) was started in 1996. Concept, intervention strategies and first results of KOPS are reported in this paper. KOPS is an ongoing 8 y follow-up study. We first enrolled a large scale cohort of 5 to 7-y-old children, providing sufficient baseline data. KOPS allows further analyses of the role of individual risk factors as well as of long-term effectiveness of different intervention strategies.RESULTS: From 1996 to 1999 a representative group of 2440 5 to 7-y-old children was recruited (ie 30.2% of the total population of 5 to 7-y-old children examined by the school physicians) and a full data set was obtained from 1640 children. Of the children, 340 (20.7%) were considered as overweight and obese, 1108 children (67.6%) were normal weight, and underweight was found in 192 children (11.7%). Of the normal-weight children, 31% or 346 (21.1% of the total population) were considered to have a risk of becoming obese. Cross-sectional data provided evidence that (i) there is an inverse social gradient in childhood overweight as well as health-related behaviours and (ii) parental fatness had a strong influence on childhood overweight. We observed considerable changes in health-related behaviours within 1 y after combined ‘school-’ and ‘family-based’ interventions. Interventions aimed to improve health-related behaviours had significant effects on the age-dependent increases in median triceps skinfolds of the whole group (from 10.9 to 11.3 mm in ‘intervention schools’ vs from 10.7 to 13.0 mm in ‘control schools’, P<0.01) as well as in percentage fat mass of overweight children (increase by 3.6 vs 0.4% per year without and with intervention, respectively; P<0.05).CONCLUSION: First results of KOPS are promising. Besides health promotion, a better school education and social support seem to be promising strategies for future interventions.

Metabolically active components of fat-free mass and resting energy expenditure in humans: recent lessons from imaging technologies.

Imaging technologies, i.e. magnetic resonance imaging (MRI), computer tomography (CT) and dual‐energy X‐ray absorptiometry (DEXA), are precise and accurate techniques used to study lean body mass and adipose tissue distribution. CT and MRI can also be used to assess metabolically active components of fat‐free mass (FFM). (Throughout this article, metabolic activity is defined with respect to oxidative metabolism.) To date a total of 116 in vivo measurements of organ masses (OM), in combination with the measurement of resting energy expenditure (REE), have been reported. These data suggest that MRI‐ or CT‐derived OM explains part (≈5–10%) of the interindividual variance in REE. The data also suggest that REE can be reconstructed from detailed body composition analysis. Calculating REE from the sum of individual OM multiplied by a constant organ tissue‐respiration rate showed a high correlation between calculated and measured REE, with only small and non‐significant differences of 83–96 kJ d–1. In addition to CT‐ and MRI‐derived OM, data are available of 244 obese and non‐obese subjects regarding the association between regional components of lean body mass (LBM, assessed by DEXA) and REE. These results suggest that measurement of LBM distribution also provides the opportunity to adjust for the non‐linearity of REE on body mass. Assessment of metabolically active components of FFM or LBM may also add to our understanding of malnutrition‐, obesity‐ and disease states‐related variance in REE. There is need for [1] standardization of imaging technology in body composition research; [2] reference data on detailed body composition, also including more recent autopsy data; [3] reducing the number of assumptions in model‐based predictions; and [4] a combination of imaging technologies with in vivo measurements of individual OM respiration.