Indices of adiposity as predictors of cardiometabolic risk and inflammation in young adults.

BACKGROUND: Studies investigating obesity and cardiometabolic risk have focused on 'at-risk' populations and methodological inconsistencies have produced equivocal findings. The present cross-sectional study investigated indices of body composition as predictors of cardiometabolic risk and their relationship with inflammation in apparently healthy young adults. METHODS: A fasting blood sample was taken from consenting adults (160 males, 32 females, aged 18-40 years) for assessment of cardiometabolic risk markers (blood pressure, lipid profiles and insulin resistance) and inflammatory markers (C-reactive protein, tumour necrosis factor-α, interleukin-6, interleukin-10 and adiponectin). Together with anthropometry, fat mass (FM) and fat-free mass (FFM) were determined by dual-energy X-ray absorptiometry. FM was expressed in absolute terms (kg), as well as relative to total body weight (%), height [FM index (FMI, kg m(-2) )] and FFM (FM : FFM,%). RESULTS: Although anthropometric indices were associated with most cardiometabolic risk markers, the strongest relationship was observed with FMI. Relative to having a low cardiometabolic risk (≤2 markers above clinically relevant cut-offs), each kg m(-2) increase in FMI, increased the likelihood of having an increased cardiometabolic risk by 29% (odds ratio = 1.29; 95% confidence interval = 1.12-1.49). Inflammatory markers were not associated with body composition or cardiometabolic risk. CONCLUSIONS: FMI was the strongest predictor of overall cardiometabolic risk but not inflammation per se. However, anthropometric indices, such as body mass index and waist-to-height ratio, remain valuable surrogate measures of adiposity in this group, particularly when risk markers are considered independently.

Plausible self-reported dietary intakes in a residential facility are not necessarily reliable.

BACKGROUND/OBJECTIVES: Comparing reported energy intakes with estimated energy requirements as multiples of basal metabolic rate (Ein:BMR) is an established method of identifying implausible food intake records. The present study aimed to examine the validity of self-reported food intakes believed to be plausible. SUBJECTS/METHODS: One hundred and eighty men and women were provided with all food and beverages for two consecutive days in a residential laboratory setting. Subjects self-reported their food and beverage intakes using the weighed food diary method (WDR). Investigators covertly measured subjects' actual consumption over the same period. Subjects also reported intakes over four consecutive days at home. BMR was measured by indirect calorimetry. RESULTS: Average reported energy intakes were significantly lower than actual intakes (11.2 and 11.8 MJ/d, respectively, P<0.001). Two-thirds (121) of the WDR were under-reported to varying degrees. Only five of these were considered as implausible using an Ein:BMR cut-off value of 1.03*BMR. Under-reporting of food and beverage intakes, as measured by the difference between reported and actual intake, was evident at all levels of Ein;BMR. Reported energy intakes were lower still (10.2 MJ/d) while subjects were at home. CONCLUSIONS: Under-recording of self-reported food intake records was extensive but very few under-reported food intake records were identified as implausible using energy intake to BMR ratios. Under-recording was evident at all levels of energy intake.

Quantifying consumer portion control practices. A cross-sectional study.

The use of portion control practices has rarely been quantified. The present study aimed to: (1) explore which portion control practices are actually used by the general population and their association with cognitive restraint, demographic background and general health interest (GHI), and (2) examine how the usage of portion control practices predicts the estimated consumption of an energy dense food (i.e. pizza). Twenty-two portion control practices were rated in terms of their frequency of use from 'never' to 'very often' by a representative sample of 1012 consumers from the island of Ireland. Three factors were extracted and named: measurement-strategy scale, eating-strategy scale, and purchasing-strategy scale. The eating-strategy scale score was the highest, while the measurement-strategy scale carried the lowest frequency score. For each strategy scale score, the strongest predictor was GHI, followed by gender. Having higher GHI and being female were independently associated with more frequent portion control. Both the eating-strategy scale score and the purchasing-strategy scale score were negatively associated with pizza portion size consumption estimates. In conclusion, while this study demonstrates that the reported use of portion control practices is low, the findings provide preliminary evidence for their validity. Further studies are needed to explore how portion control practices are used in different kinds of portion size decisions and what their contribution is to the intake of food over an extended period of time.

Variability in eating frequency in relation to adiposity measures and blood lipid profiles in British children and adolescents: findings from the National Diet and Nutrition Survey.

BACKGROUND: A very limited number of intervention trials and observational studies in adults have suggested that irregular eating frequency is associated with adverse profiles of metabolic risk factors, but evidence in younger populations is lacking. OBJECTIVE: This cross-sectional study examined the association of variability in eating frequency with adiposity measures (n=1636) and blood lipid profiles (n=843) in British children aged 4-10 years (n=818 for adiposity measures and 324 for blood lipids) and adolescents aged 11-18 years (n=818 for adiposity measures and 519 for blood lipids). DESIGN: Data from the UK National Diet and Nutrition Survey were analyzed. Dietary intake was assessed using a 7-day weighed dietary record. Eating frequency was calculated based on all eating occasions, except for those providing <210 kJ of energy. Variability in eating frequency was calculated by adding the absolute difference between the 7-day mean eating frequency and that in each day divided by the number of days (7 days), with a higher value indicating a large weekly variability in eating frequency. RESULTS: After adjustment for age, sex, social class, physical activity, ratio of reported energy intake to estimated energy requirement, body mass index z-score, eating frequency, and intakes of protein, saturated fat, total sugar and dietary fiber, variability in eating frequency was positively associated with total and low-density lipoprotein (LDL) cholesterol in children aged 4-10 years (P=0.04 and 0.03, respectively), but not in adolescents aged 11-18 years. There were no associations between eating frequency variability and other metabolic risk factors examined, including body mass index z-score, waist-to-height ratio, high-density lipoprotein cholesterol and triacylglycerol concentrations. CONCLUSIONS: Larger variability in eating frequency was associated with higher total and LDL cholesterol concentrations in children aged 4-10 years.

Eating frequency in relation to body mass index and waist circumference in British adults.

BACKGROUND: Inconsistent associations between eating frequency (EF) and adiposity may be mainly due to measurement errors of EF. OBJECTIVE: This cross-sectional study examined the association of EF with body mass index (BMI) and waist circumference (WC), by focusing on the confounding of energy misreporting and the effect of exclusion of underreporters (URs). DESIGN: Dietary intake was assessed using a 7-day weighed dietary record in 1487 British adults aged 19-64 years. EF was calculated based on all eating occasions (EF(all)), after excluding those providing no energy (EF(energy)), and after excluding those providing <210 kJ of energy (EF(⩾210 kJ)). Energy misreporting was assessed as reported energy intake divided by estimated energy requirement (EI:EER). RESULTS: The mean values (1st and 99th percentiles) of EF(all), EF(energy) and EF(⩾210 kJ) were, respectively, 7.8 (3.1, 15.3), 7.2 (2.9, 12.7), and 5.6 (2.3, 10.7) times/day in men and 7.6 (3.0, 13.9), 6.7 (2.7, 12.1), and 4.8 (1.9, 9.1) times/day in women. In the univariate analyses of the entire male population, EF(⩾210 kJ), but not EF(all) and EF(energy), was inversely associated with BMI and WC. After full adjustment (including EI:EER), all three measures of EF were positively associated with BMI and WC. In the univariate analyses of the entire female population, all three measures of EF were inversely associated with BMI and WC. After full adjustment, EF(⩾210 kJ) was positively associated with BMI and WC while EF(all) and EF(energy) showed null associations. When URs (EI:EER <0.665) were excluded, the multivariate analyses showed that EF(all) and EF(energy) were positively associated with BMI in men while EF(⩾210 kJ) was positively associated with BMI and WC in both sexes. CONCLUSIONS: We showed positive associations of EF with BMI and WC. Adjustment for EI:EER and the exclusion of URs, as well as definitions of EF, radically affected the results of the analysis.

Dietary glycemic index and glycemic load in relation to changes in body composition measures during adolescence: Northern Ireland Young Hearts Study.

BACKGROUND: Epidemiologic evidence on the influence of dietary glycemic index (GI) and glycemic load (GL) on the development of obesity is limited. OBJECTIVE: This prospective study examined the associations between dietary GI and GL and changes in body composition measures during adolescence. DESIGN: In a representative sample of Northern Irish adolescents aged 12 years at baseline and 15 years at follow-up (n=426), dietary intake was assessed by a diet history interview. Body composition measures included body mass index (BMI; kg m(-2)), BMI z-score, sum of four skinfold thicknesses, percentage body fat, fat mass index (FMI; kg m(-2)) and fat-free mass index (kg m(-2)). RESULTS: After adjustment for potential confounding factors, baseline GI was associated with increased change in FMI. Mean (95% confidence interval) values of changes in FMI according to tertiles of baseline GI were 0.41 (0.25, 0.57), 0.42 (0.26, 0.58) and 0.67 (0.51, 0.83) kg m(-2), respectively (P for trend=0.03). There was no significant association of baseline GI with changes in other body composition measures (P for trend≥0.054). Conversely, baseline GL showed no association with changes in any of the measures (P for trend≥0.41). Furthermore, changes in GI or GL were not associated with changes in any of the measures (P for trend≥0.16). CONCLUSION: Dietary GI at age 12 years was independently associated with increased change in FMI between ages 12 and 15 years in a representative sample from Northern Ireland, whereas dietary GL showed no association with changes in any of the body composition measures examined.

Perceived 'healthiness' of foods can influence consumers' estimations of energy density and appropriate portion size.

OBJECTIVE: To compare portion size (PS) estimates, perceived energy density (ED) and anticipated consumption guilt (ACG) for healthier vs standard foods. METHODS: Three pairs of isoenergy dense (kJ per 100 g) foods-healthier vs standard cereals, drinks and coleslaws-were selected. For each food, subjects served an appropriate PS for themselves and estimated its ED. Subjects also rated their ACG about eating the food on a scale of 1 (not at all guilty) to 5 (very guilty). RESULTS: Subjects (n=186) estimated larger portions of the healthier coleslaw than that of the standard version, and perceived all healthier foods to be lower in ED than their standard alternatives, despite being isoenergy dense. Higher ACG was associated with the standard foods. Portion estimates were generally larger than recommendations and the ED of the foods was underestimated. CONCLUSIONS: The larger portions selected for the 'reduced fat' food in association with lower perceived ED and ACG suggests that such nutrition claims could be promoting inappropriate PS selection and consumption behaviour. Consumer education on appropriate portions is warranted to correct such misconceptions.

Supermarket own brand foods: lower in energy cost but similar in nutritional quality to their market brand alternatives.

BACKGROUND: The present study aimed to compare the nutritional quality (NQ) and energy costs (EC) (£ MJ(-1) ) of own brand (OB) versus market brand (MB) foods in 2010 and 2012. METHODS: A list of processed foods (n = 32) was identified based on the most frequently consumed foods in the UK. Total fat, saturated fat, sugars, salt and energy density (ED) (kJ g(-1) ) in 2010 and 2012 were compared for six OB and one MB version of each food using a NQ scoring method based on the Food Standards Agency's Traffic Light System (TLS). Additional information (fruit, vegetable and nut content; protein; fibre and sodium) was recorded in 2012, and NQ was assessed using the Food Standards Agency's nutrient profiling model (NPM). The EC of the food baskets (FB) was compared in 2010 and 2012. RESULTS: There were no differences in overall NQ between OB and MB FB in 2010 (TLS, P = 0.978) or 2012 (TLS, P = 0.840; NPM, P = 0.696). However, the MB FB was highest in EC in 2010 and 2012 (both P < 0.001). There was an inverse relationship between the ED and EC of the MB foods in 2010 (r = -0.484; P = 0.005) and 2012 (r = -0.452; P = 0.009). CONCLUSIONS: The MB FB was higher in EC than the OB FB in 2010 and 2012 but not superior in overall NQ based on both the TLS and NPM.

Family eating out-of-home: a review of nutrition and health policies.

Childhood obesity is a growing problem worldwide. In recent years, out-of-home (OH) eating has been highlighted as one of the many factors contributing to the obesogenic environment. This review seeks to identify a range of existing guidelines for the provision of healthy food options for families who eat OH frequently. Nationally available nutrition policies were identified using targeted and untargeted searches of the internet to identify established strategies for providing food for children in the family eating out sector in America (US), Australia, Canada and the WHO's European Region (EUR). These were categorised on the basis of eleven pre-defined criteria including: family eating out sector included as stakeholder; inclusion of children's food OH; cost strategies for healthier food choices; provision of nutrition information for customers; nutrition training of catering staff; and monitoring and evaluation structures. Fifty-five policies were reviewed, of which 71% addressed children's food served OH, but principally only for food available in schools. Two voluntary programmes, from Colorado and Slovenia, were identified as possible best practice models as they met a majority of the evaluation criteria. The most frequently used strategy by policies to promote healthier eating OH was the provision of nutrition information on menus, while monitoring and evaluation plans were poorly incorporated into any OH strategies, thus raising issues about their effectiveness. This review has identified a range of initiatives that could be employed to make healthier eating OH more accessible for families. However, to establish best practice guidelines for healthier OH food choices further investigations are required.

Serving size guidance for consumers: is it effective?

Larger portion sizes (PS) may be inciting over-eating and contributing to obesity rates. Currently, there is a paucity of data on the effectiveness of serving size (SS) guidance. The aims of the present review are to evaluate SS guidance; the understanding, usability and acceptability of such guidance, its impact on consumers and potential barriers to its uptake. A sample of worldwide SS guidance schemes (n 87) were identified using targeted and untargeted searches, overall these were found to communicate various inconsistent and often conflicting messages about PS selection. The available data suggest that consumers have difficulty in understanding terms such as 'portion size' and 'serving size', as these tend to be used interchangeably. In addition, discrepancies between recommended SS and those present on food labels add to the confusion. Consumers generally understand and visualise SS best when expressed in terms of household measures rather than actual weights. Only a limited number of studies have examined the direct impact of SS guidance on consumer behaviour with equivocal results. Although consumers recognise that guidance on selecting SS would be helpful, they are often unwilling to act on such guidance. The challenge of achieving consumer adherence to SS guidance is formidable due to several barriers including chronic exposure to larger PS, distorted consumption norms and perceptions, the habit of 'cleaning one's plate' and language barriers for ethnic minorities. In conclusion, the impact of SS guidance on consumers merits further investigation to ensure that future guidance resonates with consumers by being more understandable, usable and acceptable.

Endothelial dysfunction associated with obesity and the effect of weight loss interventions.

Endothelial damage is central to the initiation and progression of atherosclerosis, while in addition vascular endothelial cells secrete several anti-atherogenic substances including the potent vasodilator nitric oxide. Increased adhesion molecule expression, in response to pathophysiological stimuli is perhaps the earliest indicator of compromised endothelial integrity. Obesity and adiposity are associated with an increased risk of CVD, influencing disease progression via a number of mechanisms, including enhanced endothelial activation. This review discusses possible mechanisms linking adiposity and more specifically regional fat depots with endothelial function and evaluates studies investigating the effect of weight loss on endothelial function, assessed by biochemical and physiological measurements. Overall, the research to date suggests that visceral adiposity is a stronger predictor of endothelial activation than overall adiposity, possibly mediated via the action of NEFA in circulation. While in general there is a suggestion that weight loss is associated with significant improvements in endothelial function, this is not apparent in all interventions and published literature to date provides less than convincing evidence for the effects of weight loss on endothelial activation.

Increased portion size leads to a sustained increase in energy intake over 4 d in normal-weight and overweight men and women.

Large food portions may be facilitating excess energy intake (EI) and adiposity among adults. The present study aimed to assess the extent to which EI and amounts of foods consumed are influenced by the availability of different-sized food portions. A randomised within-subject cross-over, fully residential design was used, where forty-three (twenty-one men and twenty-two women) normal-weight and overweight adults were randomly allocated to two separate 4 d periods where they were presented with either 'standard' or 'large' food portions of the same foods and beverages. The main outcome measures were the amount of food (g) and EI (MJ) consumed throughout each study period. Mean EI over 4 d was significantly higher on the large portion condition compared with the standard condition in the total group (59.1 (sd 6.6) v. 52.2 (sd 14.3) MJ; P = 0.020); men and women increased their EI by 17 % (10 (sd 6.5) MJ; P < 0.001) and 10 % (4 (sd 6.5) MJ; P = 0.005) respectively when served the large food portions relative to the standard food portions. The increased intakes were sustained over the 4 d in the large portion condition with little evidence of down-regulation of EI and food intake being made by subjects. Increased food portion size resulted in significant and sustained increases in EI in men and women over 4 d under fully residential conditions. The availability and consumption of larger portions of food may be a significant factor contributing to excess EI and adiposity.

Added sugars and micronutrient dilution.

There is increasing concern that high intakes of added sugars promote micronutrient dilution. However, the overall conclusion to emerge from the existing evidence base is that associations between reported intakes of added sugars and intakes of micronutrients are inconsistent and often non-linear, both across and within age groups, and between the genders. If a nutrient displacement effect does exist, a high consumption of added sugar does not necessarily compromise overall micronutrient intakes and similarly, consuming less added sugar is no guarantee that micronutrient intakes will be optimized. Clarification of this issue has been beset by methodological and conceptual difficulties. The observed associations between added sugars and micronutrient intake have been heavily contingent on both the definition of sugars chosen and the analytical approach used for adjusting for differences in reported energy intake. These issues have been further compounded by mis-reporting of food intake of unknown direction and magnitude and the cut-offs used to determine 'inadequate' micronutrient intakes which vary over time and between studies and countries. In the absence compelling evidence that micronutrient intakes are compromised by a high consumption of added sugars, it may now be appropriate to question the legitimacy of the nutrient dilution hypothesis as it is highly likely that it is oversimplifying more subtle and complex dietary issues. Recommendations for further research are made to help bring resolution to these issues.

The prevalence of abnormal eating behaviour in a representative sample of the French diabetic population.

AIM: To assess the relationship between abnormal eating behaviour (AEB) and diabetes in a sample of French adult patients with type 1 (T1D) and type 2 (T2D) diabetes. METHODS: Ninety-four consecutively recruited patients self-completed a series of validated questionnaires. RESULTS: Over one-fourth of men with T1D (26%) or T2D (27%) and 11% of female T2D patients reported consistent and pathological overeating or binge-eating during the previous six months. Glycaemic control in these T1D patients was poorer than in T1D patients defined as normal eaters (NORM) (11.9% versus 9.6%), but did not reach statistical significance (P=0.08), and no significant difference was observed in the T2D group (P=0.61) either. T2D patients reported being markedly more restrained when eating than did the T1D patients (P=0.002), and their restraint increased along with their BMI (P<0.001). Patients who overate or binged also reported greater general hunger (P=0.02) and disinhibition (P=0.003) than did the NORM patients. CONCLUSION: AEB is present in French diabetic patients at levels that are probably higher than among the general population. These results highlight the need for: (1) greater awareness among diabetes clinicians of the problem; (2) regular screening of diabetic patients for AEB; and (3) adaptation of therapeutic and dietary recommendations for this patient subgroup.

Tracking of energy and nutrient intakes from adolescence to young adulthood: the experiences of the Young Hearts Project, Northern Ireland.

OBJECTIVE: To assess tracking of energy and nutrient intakes between adolescence and young adulthood. DESIGN: Longitudinal study of a random sample of adolescents (aged 15 years at baseline). The extent of tracking of dietary intakes (assessed by diet history) was investigated using weighted kappa statistics (kappa). SETTING: Northern Ireland population survey. SUBJECTS: Adolescents who participated in the Young Hearts Project, Northern Ireland at age 15 years, and subsequently at young adulthood aged between 20 and 25 years (n=245 males, n=231 females). RESULTS: Despite overall increases in height and weight (both P<0.001), increases in body mass index in males (P<0.001) and body fatness in females (P<0.001), median reported intakes of energy (kJ kg(-1) day(-1)), carbohydrate (g day(-1)) and fat (g day(-1)) decreased (all P<0.001) over time. Expressed as nutrient densities (per MJ), diets at young adulthood were overall richer in thiamin, vitamin B6, total folate (all P<0.001), vitamin C (P<0.01) and vitamin D (P<0.05). Whereas the nutrient density of the males' diets decreased over time for calcium (P<0.05) and vitamin A (P<0.001), iron and riboflavin densities increased in the females' diet (P<0.001). Tracking of energy (MJ day(-1)) and nutrient intakes (expressed per MJ day(-1)) at the individual level was only poor to fair (all kappa<0.25), indicating substantial drift of subjects between the low, medium and high classes of intake with increasing age. CONCLUSIONS: These data suggest that individual dietary patterns exhibited at 15 years of age are unlikely to be predictive of dietary intakes at young adulthood.

Resting energy expenditure is not increased in mildly hyperglycaemic obese diabetic patients.

Resting energy expenditure (REE) is believed to be increased in type 2 diabetes, an increase that is associated with deteriorating glucose tolerance during its development. Meanwhile, insulin resistance, a state linked to obesity and observed in all type 2 diabetic patients, is associated with reduced REE. Our aim was to compare REE in obese patients with and without diabetes. REE, body composition (total body water, density, percentage fat and fat-free mass: 3-compartment model) and metabolic control were assessed in fifty obese Caucasian patients with diabetes (glycated haemoglobin level 7.6 (SD 1.5) %) and fifty obese patients who were non-diabetic. Despite being more overweight and younger, obese non-diabetic patients had an absolute REE (7.73 (SD 1.44) v. 8.12 (SD 1.37) MJ; P=0.17) and percentage fat-free mass similar to those of obese diabetic patients. Even when adjusted for differences in body composition, REE remained similar in both groups. Furthermore, REE (absolute and adjusted) was unaffected by both glucose level and control (glycated haemoglobin), with fat-free mass being the only determinant of REE. We conclude that REE is not necessarily increased by the presence of diabetes in obese people.

Investigation of the medium-term effects of Olibratrade mark fat emulsion on food intake in non-obese subjects.

OBJECTIVE: To investigate the effect of Olibra fat emulsion on medium-term food intake and appetite in non-obese subjects. DESIGN: Double-blind, placebo-controlled, within-subject crossover. SETTING: University of Ulster, Coleraine. SUBJECTS: A total of 28 subjects (14 male, 14 female). INTERVENTIONS: Subjects were randomly assigned to receive either a 200 g portion of test (5 g of Olibra fat) or control (5 g milk fat) yoghurt for breakfast for 2 x 3 week 'study' phases, separated by a 3-week 'wash-out' phase. On days 1, 8 and 22 of the study phases, food intake 4 h post-consumption of the yoghurt was assessed by pre- and post-covert weighing at an ad libitum buffet-style test lunch. Throughout each of these study days, appetite was assessed using visual analogue scales (VAS) at regular intervals. For the remainder of the study days, and the following 24 h ('post-study days'), subjects reported their food intake using weighed dietary records. RESULTS: Consumption of the Olibra emulsion had no significant effect on mean energy, macronutrient or amounts of food consumed at the lunch 4 h post-consumption. Self-reported food intakes indicated that there was no significant effect of the emulsion on energy intakes for the remainder of each study day and post-study days. There was considerable individual variation in food intakes following consumption of the Olibra emulsion, with 46, 59 and 57% of subjects reducing their energy intakes at lunch on days 1, 8 and 22. There was no consistent effect of the emulsion on appetite ratings. CONCLUSIONS: In contrast to earlier studies, there was no evidence of a short- or medium-term effect of the Olibra emulsion on food intake or appetite. This could be owing to numerous confounding factors influencing eating behaviour and/or the different study design used in the present study.

Associations between daily food intake and excess adiposity in Irish adults: towards the development of food-based dietary guidelines for reducing the prevalence of overweight and obesity.

BACKGROUND: The prevalence of obesity has nearly doubled in Ireland since 1990 and over half of the population has a large waist circumference (WC). No food-based, dietary guidelines exist in Ireland for a reduction in the prevalence of body fat or obesity. OBJECTIVE: To examine the association between daily food intake and categories of body mass index and WC for the development of dietary guidelines to combat obesity. DESIGN: Cross-sectional study of a random representative sample of 1379 adults aged 18-64 years from Northern Ireland and the Republic of Ireland. MEASUREMENTS: Weight, height and WC were measured according to standard procedures. Diet was assessed using a 7-day food diary from which 28 food groups were generated and entered into logistic regression analysis. RESULTS: Higher mean daily consumption of most of the 28 food groups was associated with an increased likelihood of being classified as obese or at waist action level 2, compared to normal weight and normal WC. The strongest associations were found for savoury snacks, butter and full fat spreads. Contrary to popular opinion, not one individual food group but rather a combination of many foods was associated with excess adiposity. CONCLUSIONS: Body mass index and WC in adults are strongly influenced by the amount of food consumed. Public health policies for a reduction in body fat and obesity may be more effective if the emphasis is placed on a reduction of food and beverages consumed as opposed to the traditional dietary recommendations for macronutrients.

Childhood obesity prevention studies: lessons learned and to be learned.

OBJECTIVE: To provide an overview of methodological issues in the design, delivery and evaluation of childhood obesity prevention programmes. DESIGN: Review of existing literature. SETTING: International. RESULTS: Interventions have varied considerably with regard to their design, subject selection criteria, sample size, attrition rates, intervention components and duration of both the intervention and the follow-up phases. However, overall, there is only a limited body of consistent, high-quality evidence on which valid and generalisable conclusions can be drawn about best practices for the prevention of childhood obesity. CONCLUSIONS: Although the rationale for targeting children and adolescents through primary prevention is now compelling, effective obesity prevention remains elusive. There is increasing consensus that prevention of childhood obesity necessitates multifaceted health promotion interventions based on population health principles. By definition, such interventions should have a range of outcome indicators of effectiveness, generalisability and sustainability, not just the traditional ones focused on individual lifestyle behaviour change. Given the complexity and intricacy of population-based intervention programmes, multiple methods of data collection which combine both qualitative and quantitative approaches will need to be fully exploited in order to move towards evidence-based practice in the future.

Health and lifestyle characteristics of older European adults: the ZENITH study.

OBJECTIVE: To describe health and lifestyle factors of participants in the ZENITH study. DESIGN: A prospective multicentre intervention study employing a randomised double-blind design. PARTICIPANTS: Community dwelling older adults (n = 387), aged 55-87 y were recruited from regions in France, Italy and the UK. INTERVENTION: A self-report questionnaire comprising socio-demographic variables, dietary habits, physical activity in the home, at work and recreation. RESULTS: Participants differed with regards dietary habits and physical activity for each region. Recreational activity was higher in France and women generally tend to perform less hours of recreational activity per week than men. CONCLUSIONS: The differences found for these regions of Europe in relation to lifestyle factors will affect health and well-being within these countries and may mediate the impact of zinc supplementation on various biological and psychological parameters.