Food portion sizes, obesity, and related metabolic complications in children and adolescents / Tamaño de las porciones de alimentos, obesidad y complicaciones metabólicas asociadas en niños y adolescentes

The purpose of this narrative review is to provide evidence for the impact of food portion sizes on the development of obesity in children and adolescents. Strategies are needed on portion size estimation and on the relationship of portion size with certain health problems such as obesity, insulin resistance, and emotional eating in all age groups, in order to provide information for parents, teachers, and health professionals aiming to promote healthy eating. A wide range of controlled laboratory studies have found that portion size (PS) had the strongest effect on the amount of food consumed. The effect of PS on total energy intake has been already observed with different types of foods and beverages, especially with energy-dense foods. The influence of large PS was persistent and happened regardless of demographic characteristics such as age, gender, income level, or body mass index. Although a direct causal link between PS and obesity remains controversial, some health and dietetics organizations recommend to moderate PS, especially for energy-dense foods. Research studies in both laboratory and free-living contexts are needed to determine the causal link between increased PS, obesity, and related metabolic complications in children and adolescents

El objetivo de esta revisión narrativa es proporcionar evidencia actual sobre el impacto del tamaño de las porciones de alimentos sobre el desarrollo de la obesidad en niños y adolescentes. Son necesarias estrategias sobre la estimación del tamaño de las porciones y su relación con ciertos problemas de salud como la obesidad, la resistencia a la insulina y la alimentación emocional en todos los grupos de edad, a fin de proporcionar una comunicación efectiva para los padres, los profesores y los profesionales de la salud, teniendo por objetivo promover una alimentación saludable. Varios son los estudios que encontraron asociaciones positivas entre el tamaño de la porción y la cantidad de alimentos consumidos. También se ha observado que el tamaño de la porción influye en la ingesta total de energía, especialmente en el caso de los alimentos de elevada densidad energética, siendo este efecto independiente de las características demográficas, como la edad, el género, el nivel socioeconómico o el índice de masa corporal. La relación causal entre el tamaño de las porciones y la obesidad sigue siendo controvertida; algunas organizaciones de salud y dietética recomiendan moderar los tamaños de las porciones, especialmente tratándose de alimentos de elevada densidad energética. Por ello se necesitan más estudios a corto y largo plazo que puedan determinar la relación causal entre el aumento del tamaño de las porciones, la obesidad y las complicaciones metabólicas asociadas en niños y adolescentes

The development of food portion sizes suitable for 4-18-year-old children used in a theoretical meal plan meeting energy and nutrient requirements.

BACKGROUND: Healthy eating guidelines for school-aged children are available but without advice on portion sizes. This is a concern because consuming large portions is associated with an increased risk of overweight/obesity. The present study aimed to calculate recommended portion sizes for school-aged children based on weight for age and use them to develop a meal plan to meet nutritional needs within energy requirements. METHODS: Portion size data on foods consumed by school-aged children (4-18 years) were extracted from two sources: (i) British National Diet and Nutrition Survey (1997) and (ii) Avon Longitudinal Study of Parents and Children (1997-2006). Foods were allocated to groups based on the UK Eatwell Guide and the US My Plate Model. Portion sizes were developed for a variety of foods. A meal plan that included portion size guidance and met healthy eating guidelines was developed based on the number of portions of each food group needed to meet dietary requirements. RESULTS: Portion sizes were developed for 131 foods that were commonly eaten by children in age groups 4-6, 7-10, 11-14 and 15-18 years. The meal plan met requirements for energy and nutrients as specified by UK dietary reference values, except for vitamin D for which there are few dietary sources. CONCLUSIONS: Food portion sizes informed by usual intake in UK children can help inform dietary advice for a range of childhood settings and for parents. The meal plan included a wide variety of foods to encourage dietary diversity and meet energy and nutrient needs for school-aged children.

Development and validation of a photographic atlas of food portions for accurate quantification of dietary intakes in China.

BACKGROUND: Accurate estimation of food portion sizes remains an important challenge in dietary data collection. The present study aimed to develop a food atlas with adequate visual reference to improve the accuracy of dietary surveys in China. METHODS: A food atlas for dietary surveys in China was developed using three visual reference systems, namely, regularly placed food portions, the two-dimensional background coordinates and common objects known in daily life. The atlas was validated by estimating a meal before and after using the food atlas, and differences in weight estimation were compared using a paired t-test. In total, 50 college students participated in the study. RESULTS: After determination of food varieties; design of the food display; purchase, processing, cooking and weighing of food; photographing food; post-image processing and data processing, a total of 799 pictures of 303 types of food and two types of tableware were produced. The mean value of food weight estimated with the atlas was closer to the actual weight, and the variation range of these values was smaller and more stable than that estimated without the atlas. The differences estimated before and after using the atlas for all foods were significant (P < 0.05). Comparing the differences in weight before using the atlas, the error ranges of food samples were reduced. CONCLUSIONS: A food atlas has been developed for a retrospective dietary survey in China, which can be used to enable a better understanding of nutritional adequacy in the Chinese population.

Validation of a digitally displayed photographic food portion-size estimation aid among women in urban and rural Malawi.

OBJECTIVE: To validate digitally displayed photographic portion-size estimation aids (PSEA) against a weighed meal record and compare findings with an atlas of printed photographic PSEA and actual prepared-food PSEA in a low-income country. DESIGN: Participants served themselves water and five prepared foods, which were weighed separately before the meal and again after the meal to measure any leftovers. Participants returned the following day and completed a meal recall. They estimated the quantities of foods consumed three times using the different PSEA in a randomized order. SETTING: Two urban and two rural communities in southern Malawi. PARTICIPANTS: Women (n 300) aged 18-45 years, equally divided by urban/rural residence and years of education (≤4 years and ≥5 years). RESULTS: Responses for digital and printed PSEA were highly correlated (>91 % agreement for all foods, Cohen's κw = 0·78-0·93). Overall, at the individual level, digital and actual-food PSEA had a similar level of agreement with the weighed meal record. At the group level, the proportion of participants who estimated within 20 % of the weighed grams of food consumed ranged by type of food from 30 to 45 % for digital PSEA and 40-56 % for actual-food PSEA. Digital PSEA consistently underestimated grams and nutrients across foods, whereas actual-food PSEA provided a mix of under- and overestimates that balanced each other to produce accurate mean energy and nutrient intake estimates. Results did not differ by urban and rural location or participant education level. CONCLUSIONS: Digital PSEA require further testing in low-income settings to improve accuracy of estimations.

Progress Evaluation for Transnational Restaurant Chains to Reformulate Products and Standardize Portions to Meet Healthy Dietary Guidelines and Reduce Obesity and Non-Communicable Disease Risks, 2000-2018: A Scoping and Systematic Review to Inform Policy.

Transnational restaurant chains sell food and beverage products in 75 to 139 countries worldwide linked to obesity and non-communicable diseases (NCDs). This study examined whether transnational restaurant chains reformulated products and standardized portions aligned with healthy dietary guidelines and criteria. Firstly, we describe the transnational restaurant industry structure and eating trends. Secondly, we summarize results from a scoping review of healthy dietary guidelines for restaurants. Thirdly, we describe a systematic review of five electronic databases (2000-2018) to identify studies on nutrient profile and portion size changes made by transnational restaurants over 18 years. We used Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, identified 179 records, and included 50 studies conducted in 30 countries across six regions. The scoping review found a few expert-recommended targets for restaurants to improve offerings, but no internationally accepted standard for portions or serving sizes. The systematic review results showed no standardized assessment methods or metrics to evaluate transnational chain restaurants' practices to improve menu offerings. There was wide variation within and across countries, regions, firms, and chains to reduce energy, saturated and trans fats, sodium, and standardized portions. These results may inform future research and encourage transnational chain restaurants to offer healthy product profiles and standardized portions to reduce obesity and NCD risks worldwide.

Comparison between serving sizes of cakes and muffins sold in Australian supermarkets and coffee shop chains.

AIM: Cakes and muffins are commonly consumed discretionary foods that have increased significantly in portion size over the past decades. The present study aimed to (i) investigate serving sizes and energy per serving of cakes and muffins sold in supermarkets and coffee chains, (ii) compare to standard discretionary serves and (iii) propose feasible and appropriate serving size recommendations. METHODS: Serving sizes and energy content of cakes and muffins were collected from four major Australian supermarkets (n = 219) and eight coffee chains (n = 248) between March and April 2017 and classified into eight categories and compared using Mann-Whitney tests. Median energy per serving of cakes and muffins from supermarkets and coffee chains were compared to the Australian Dietary Guidelines standard serve of 600 kJ for discretionary food. RESULTS: The median serving size of cakes and muffins from supermarkets, 58 g (interquartile range, IQR: 47-83) and their energy content, 915 kJ (IQR: 745-1243) were significantly smaller compared with coffee chain equivalents, 148 g (IQR: 115-171, P < 0.001) and 1805 kJ (IQR: 1436-2004, P < 0.001), respectively. The majority of cakes and muffins exceeded the Australian Dietary Guidelines standard serve (78% from supermarkets and 99% from coffee chains). CONCLUSIONS: The larger servings of cakes and muffins sold in coffee chains contain nearly double the energy content of smaller servings sold in supermarkets. We recommend reference serving sizes for industry and food retail are set for this category, in combination with consumer education to guide consumers to select appropriate portion sizes.

Feasibility of working with a wholesale supplier to co-design and test acceptability of an intervention to promote smaller portions: an uncontrolled before-and-after study in British Fish & Chip shops.

OBJECTIVES: To explore the feasibility of working with a wholesale supplier to co-design and deliver, and to assess the acceptability of, an intervention to promote smaller portions in Fish & Chip shops. DESIGN: Uncontrolled before-and-after study. SETTING: Fish & Chip shops in northern England, 2016. PARTICIPANTS: Owners (n=11), a manager and customers (n=46) of Fish & Chip shops; and intervention deliverers (n=3). INTERVENTION: Supplier-led, three-hour engagement event with shop owners and managers, highlighting the problem of excessive portion sizes and potential ways to reduce portion sizes; provision of box packaging to serve smaller portions; promotional posters and business incentives. DATA COLLECTION: In-store observations and sales data collected at baseline and postintervention. Exit survey with customers. Semistructured interviews with owners/managers and intervention deliverers postintervention. RESULTS: Twelve Fish & Chip shops were recruited. Observational data were collected from eight shops: at baseline, six shops did not promote the availability of smaller portion meals; at follow-up, all eight did and five displayed the promotional poster. Seven out of 12 shops provided sales data and all reported increased sales of smaller portion meals postintervention. Of 46 customers surveyed: 28% were unaware of the availability of smaller portion meals; 20% had bought smaller portion meals; and 46% of those who had not bought these meals were interested to try them in the future. Interviews revealed: owners/managers found the intervention acceptable but wanted a clearer definition of a smaller portion meal; the supplier valued the experience of intervention co-production and saw the intervention as being compatible with their responsibility to drive innovation. CONCLUSIONS: The co-design of the intervention with a supplier was feasible. The partnership facilitated the delivery of an intervention that was acceptable to owners and customers. Sales of smaller meal packaging suggest that promotion of such meals is viable and may be sustainable.

Analysis of the National Adult Nutrition Survey (Ireland) and the Food4Me Nutrition Survey Databases to Explore the Development of Food Labelling Portion Sizes for the European Union.

The present study set out to explore the option of developing food portion size for nutritional labelling purposes using two European Union (EU) dietary surveys. The surveys were selected as they differed in (a) methodologies (food diary versus food frequency questionnaire), (b) populations (Irish National Adult Nutrition Survey (NANS) versus a seven-country survey based on the pan EU study Food4Me), (c) food quantification (multiple options versus solely photographic album) and (d) duration (4 consecutive days versus recent month). Using data from these studies, portion size was determined for 15 test foods, where portion size was defined as the median intake of a target food when consumed. The median values of the portion sizes derived from both the NANS and Food4Me surveys were correlated (r = 0.823; p < 0.00) and the mean of the two survey data sets were compared to US values from the Recognized as Customarily Consumed (RACC) database. There was very strong agreement across all food categories between the averaged EU and the US portion size (r = 0.947; p < 0.00). It is concluded that notwithstanding the variety of approaches used for dietary survey data in the EU, the present data supports using a standardized approach to food portion size quantification for food labelling in the EU.

Examining the Accuracy and Use of Portion Size Estimation Aids in Parents of Children With Obesity: A Randomized Controlled Trial.

OBJECTIVE: To determine parents' (1) accuracy in using portion size estimation aids (PSEAs) to estimate portion sizes and (2) use of PSEAs at home. METHODS: Parents (n = 37) of children in a pediatric weight management clinic were recruited, enrolled in a parallel-design, randomized, controlled trial, and assigned to receive a 2-dimensional (2D) or 3D PSEA. Percent absolute estimation accuracy was examined across groups and food types. Survey responses were organized according to frequencies and percentages were calculated. RESULTS: Main effects of group, food type, and group × food type interaction were significant (all P < .05). The 2D PSEAs yielded more accurate estimates of portion sizes for amorphous foods. Overall, parents' estimation accuracy was poor. Participants were satisfied and found the PSEAs to be useful. CONCLUSIONS AND IMPLICATIONS: The 2D PSEAs led to greater accuracy in estimating portions of amorphous foods. Parents showed poor accuracy in estimating portion sizes. This study highlights the role of dietitians and nutrition educators in enhancing portion estimation accuracy.

Large Variations in Declared Serving Sizes of Packaged Foods in Australia: A Need for Serving Size Standardisation?

Declared serving sizes on food packaging are unregulated in Australia, and variations in serving size within similar products reduces the usability of this information. This study aimed to (i) assess the variations in declared serving sizes of packaged foods from the Five Food Groups, and (ii) compare declared serving sizes to the Australian Dietary Guidelines standard serves and typical portion sizes consumed by Australian adults. Product information, including serving size, was collected for 4046 products from four major Australian retailers. Within product categories from the Five Food Groups, coefficients of variation ranged from 0% to 59% for declared serving size and 9% to 64% for energy per serving. Overall, 24% of all products displayed serving sizes similar (within ±10%) to the standard serves, and 23-28% were similar to typical portion sizes consumed by adults, for females and males, respectively. In conclusion, there is substantial variation in the declared serving sizes of packaged foods from the Five Food Groups, and serving sizes are not aligned with either the Dietary Guidelines or typical portion sizes consumed. Future research into effective means of standardising serving sizes is warranted.

A Comparison of Food Portion Size Estimation by Older Adults, Young Adults and Nutritionists.

OBJECTIVES: To investigate the ability of older adults, younger adults and nutritionists to assess portion size using traditional methods versus a computer-based method. This was to inform the development of a novel dietary assessment method for older adults "The NANA system". DESIGN: Older and younger adults assessed the portion size of self-served portions of foods from a buffet style set up using traditional and computerised portion size assessment aids. Nutritionists assessed the portion size of foods from digital photographs using computerised portion size aids. These estimates were compared to known weights of foods using univariate analyses of covariance (ANCOVA). SETTING: The University of Sheffield, United Kingdom. SUBJECTS: Forty older adults (aged 65 years and over), 41 younger adults (aged between 18 and 40 years) and 25 nutritionists. RESULTS: There was little difference in the abilities of older and younger adults to assess portion size using both assessment aids with the exception of small pieces morphology. Even though the methods were not directly comparable among the test groups, there was less variability in portion size estimates made by the nutritionists. CONCLUSION: Older adults and younger adults are similar in their ability to assess food portion size and demonstrate wide variability of estimation compared to the ability of nutritionists to estimate portion size from photographs. The results suggest that the use of photographs of meals consumed for portion size assessment by a nutritionist may improve the accuracy of dietary assessment. Improved portion size assessment aids are required for all age groups.

Research into food portion size: methodological aspects and applications.

Portion sizes for certain foods have been increasing dramatically in recent years alongside obesity rates, concurring with the phenomenon of the portion size effect (more is consumed when more is offered). Portion size may be defined based on different purposes such as for dietary assessment, or therapeutic advice or food labelling, resulting in a variety of measurement methods and specifications. This situation has resulted in disagreements on establishing portion size recommendations by manufacturers, food distributors, restaurants, health professionals and policy makers, contributing to confusion amongst consumers on the amounts of food to be consumed, and potentially increasing the likelihood of overeating and other obesity-related behaviours. Such variability is also reflected in the research field making comparison across studies on portion size difficult. The aim of this review is to provide an overview of definitions and methods used in research to evaluate portion-size related outcomes, including methods to estimate amounts consumed by individuals as part of dietary assessment; methods to analyse cognitive mechanisms related to portion size behaviour; and methods to evaluate the impact of portion size manipulations as well as individual plus environmental factors on portion size behaviour. Special attention has been paid to behavioural studies exploring portion size cognitive processes given the lack of previous methodological reviews in this area. This information may help researchers, clinicians and other stakeholders to establish clearer definitions of portion size in their respective areas of work and to standardise methods to analyse portion size effects.

The international food unit: a new measurement aid that can improve portion size estimation.

BACKGROUND: Portion size education tools, aids and interventions can be effective in helping prevent weight gain. However consumers have difficulties in estimating food portion sizes and are confused by inconsistencies in measurement units and terminologies currently used. Visual cues are an important mediator of portion size estimation, but standardized measurement units are required. In the current study, we present a new food volume estimation tool and test the ability of young adults to accurately quantify food volumes. The International Food Unit™ (IFU™) is a 4x4x4 cm cube (64cm3), subdivided into eight 2 cm sub-cubes for estimating smaller food volumes. Compared with currently used measures such as cups and spoons, the IFU™ standardizes estimation of food volumes with metric measures. The IFU™ design is based on binary dimensional increments and the cubic shape facilitates portion size education and training, memory and recall, and computer processing which is binary in nature. METHODS: The performance of the IFU™ was tested in a randomized between-subject experiment (n = 128 adults, 66 men) that estimated volumes of 17 foods using four methods; the IFU™ cube, a deformable modelling clay cube, a household measuring cup or no aid (weight estimation). Estimation errors were compared between groups using Kruskall-Wallis tests and post-hoc comparisons. RESULTS: Estimation errors differed significantly between groups (H(3) = 28.48, p < .001). The volume estimations were most accurate in the group using the IFU™ cube (Mdn = 18.9%, IQR = 50.2) and least accurate using the measuring cup (Mdn = 87.7%, IQR = 56.1). The modelling clay cube led to a median error of 44.8% (IQR = 41.9). Compared with the measuring cup, the estimation errors using the IFU™ were significantly smaller for 12 food portions and similar for 5 food portions. Weight estimation was associated with a median error of 23.5% (IQR = 79.8). CONCLUSIONS: The IFU™ improves volume estimation accuracy compared to other methods. The cubic shape was perceived as favourable, with subdivision and multiplication facilitating volume estimation. Further studies should investigate whether the IFU™ can facilitate portion size training and whether portion size education using the IFU™ is effective and sustainable without the aid. A 3-dimensional IFU™ could serve as a reference object for estimating food volume.

Acceptability and potential effectiveness of commercial portion control tools amongst people with obesity.

Exposure to large portion sizes is a risk factor for obesity. Specifically designed tableware may modulate how much is eaten and help with portion control. We examined the experience of using a guided crockery set (CS) and a calibrated serving spoon set (SS) by individuals trying to manage their weight. Twenty-nine obese adults who had completed 7-12 weeks of a community weight-loss programme were invited to use both tools for 2 weeks each, in a crossover design, with minimal health professional contact. A paper-based questionnaire was used to collect data on acceptance, perceived changes in portion size, frequency, and type of meal when the tool was used. Scores describing acceptance, ease of use and perceived effectiveness were derived from five-point Likert scales from which binary indicators (high/low) were analysed using logistic regression. Mean acceptance, ease of use and perceived effectiveness were moderate to high (3·7-4·4 points). Tool type did not have an impact on indicators of acceptance, ease of use and perceived effectiveness (P>0·32 for all comparisons); 55 % of participants used the CS on most days v. 21 % for the SS. The CS was used for all meals, whereas the SS was mostly used for evening meals. Self-selected portion sizes increased for vegetables and decreased for chips and potatoes with both tools. Participants rated both tools as equally acceptable, easy to use and with similar perceived effectiveness. Formal trials to evaluate the impact of such tools on weight control are warranted.

High variation in manufacturer-declared serving size of packaged discretionary foods in Australia.

Despite the potential of declared serving size to encourage appropriate portion size consumption, most countries including Australia have not developed clear reference guidelines for serving size. The present study evaluated variability in manufacturer-declared serving size of discretionary food and beverage products in Australia, and how declared serving size compared with the 2013 Australian Dietary Guideline (ADG) standard serve (600 kJ). Serving sizes were obtained from the Nutrition Information Panel for 4466 packaged, discretionary products in 2013 at four large supermarkets in Sydney, Australia, and categorised into fifteen categories in line with the 2013 ADG. For unique products that were sold in multiple package sizes, the percentage difference between the minimum and the maximum serving size across different package sizes was calculated. A high variation in serving size was found within the majority of food and beverage categories - for example, among 347 non-alcoholic beverages (e.g. soft drinks), the median for serving size was 250 (interquartile range (IQR) 250, 355) ml (range 100-750 ml). Declared serving size for unique products that are available in multiple package sizes also showed high variation, particularly for chocolate-based confectionery, with median percentage difference between minimum and maximum serving size of 183 (IQR 150) %. Categories with a high proportion of products that exceeded the 600 kJ ADG standard serve included cakes and muffins, pastries and desserts (≥74 % for each). High variability in declared serving size may confound interpretation and understanding of consumers interested in standardising and controlling their portion selection. Future research is needed to assess if and how standardising declared serving size might affect consumer behaviour.

Comparison of the portion size and frequency of consumption of 156 foods across seven European countries: insights from the Food4ME study.

There are no standardised serving/portion sizes defined for foods consumed in the European Union (EU). Typical serving sizes can deviate significantly from the 100 g/100 ml labelling specification required by the EU legislation. Where the nutritional value of a portion is specified, the portion size is determined by the manufacturers. Our objective was to investigate the potential for standardising portion sizes for specific foods, thereby ensuring complementarity across countries. We compared portion size for 156 food items measured using a food frequency questionnaire across the seven countries participating in the Food4me study. The probability of consuming a food and the frequency of consumption differed across countries for 93% and 58% of the foods, respectively. However, the individual country mean portion size differed from the average across countries in only 16% of comparisons. Thus, although dietary choices vary markedly across countries, there is much less variation in portion sizes. Our results highlight the potential for standardisation of portion sizes on nutrition labels in the EU.

Package size and manufacturer-recommended serving size of sweet beverages: a cross-sectional study across four high-income countries.

OBJECTIVE: To assess the mean package size and manufacturer-recommended serving size of sweet beverages available in four high-income countries: Australia, Canada, the Netherlands and New Zealand. DESIGN: Cross-sectional surveys. SETTING: The two largest supermarket chains of each country in 2012/2013. SUBJECTS: Individual pack size (IPS) drinks (n 891) and bulk pack size (BPS) drinks (n 1904). RESULTS: For all IPS drinks, the mean package size was larger than the mean serving size (mean (sd)=412 (157) ml and 359 (159) ml, respectively). The mean (sd) package size of IPS drinks was significantly different for all countries (range: Australia=370 (149) ml to New Zealand=484 (191) ml; P<0·01). The mean (sd) package size of Dutch BPS drinks (1313 (323) ml) was significantly smaller compared with the other countries (New Zealand=1481 (595) ml, Australia=1542 (595) ml, Canada=1550 (434) ml; P<0·01). The mean (sd) serving size of BPS drinks was significantly different across all countries (range: Netherlands=216 (30) ml to Canada=248 (31) ml; P<0·00). New Zealand had the largest package and serving sizes of the countries assessed. In all countries, a large number of different serving sizes were used to provide information on the amount appropriate to consume in one sitting. CONCLUSIONS: At this point there is substantial inconsistency in package sizes and manufacturer-recommended serving sizes of sweet beverages within and between four high-income countries, especially for IPS drinks. As consumers do factor serving size into their judgements of healthiness of a product, serving size regulations, preferably set by governments and global health organisations, would provide consistency and assist individuals in making healthier food choices.

Portion, package or tableware size for changing selection and consumption of food, alcohol and tobacco.

BACKGROUND: Overeating and harmful alcohol and tobacco use have been linked to the aetiology of various non-communicable diseases, which are among the leading global causes of morbidity and premature mortality. As people are repeatedly exposed to varying sizes and shapes of food, alcohol and tobacco products in environments such as shops, restaurants, bars and homes, this has stimulated public health policy interest in product size and shape as potential targets for intervention. OBJECTIVES: 1) To assess the effects of interventions involving exposure to different sizes or sets of physical dimensions of a portion, package, individual unit or item of tableware on unregulated selection or consumption of food, alcohol or tobacco products in adults and children.2) To assess the extent to which these effects may be modified by study, intervention and participant characteristics. SEARCH METHODS: We searched CENTRAL, MEDLINE, EMBASE, PsycINFO, eight other published or grey literature databases, trial registries and key websites up to November 2012, followed by citation searches and contacts with study authors. This original search identified eligible studies published up to July 2013, which are fully incorporated into the review. We conducted an updated search up to 30 January 2015 but further eligible studies are not yet fully incorporated due to their minimal potential to change the conclusions. SELECTION CRITERIA: Randomised controlled trials with between-subjects (parallel-group) or within-subjects (cross-over) designs, conducted in laboratory or field settings, in adults or children. Eligible studies compared at least two groups of participants, each exposed to a different size or shape of a portion of a food (including non-alcoholic beverages), alcohol or tobacco product, its package or individual unit size, or of an item of tableware used to consume it, and included a measure of unregulated selection or consumption of food, alcohol or tobacco. DATA COLLECTION AND ANALYSIS: We applied standard Cochrane methods to select eligible studies for inclusion and to collect data and assess risk of bias. We calculated study-level effect sizes as standardised mean differences (SMDs) between comparison groups, measured as quantities selected or consumed. We combined these results using random-effects meta-analysis models to estimate summary effect sizes (SMDs with 95% confidence intervals (CIs)) for each outcome for size and shape comparisons. We rated the overall quality of evidence using the GRADE system. Finally, we used meta-regression analysis to investigate statistical associations between summary effect sizes and variant study, intervention or participant characteristics. MAIN RESULTS: The current version of this review includes 72 studies, published between 1978 and July 2013, assessed as being at overall unclear or high risk of bias with respect to selection and consumption outcomes. Ninety-six per cent of included studies (69/72) manipulated food products and 4% (3/72) manipulated cigarettes. No included studies manipulated alcohol products. Forty-nine per cent (35/72) manipulated portion size, 14% (10/72) package size and 21% (15/72) tableware size or shape. More studies investigated effects among adults (76% (55/72)) than children and all studies were conducted in high-income countries - predominantly in the USA (81% (58/72)). Sources of funding were reported for the majority of studies, with no evidence of funding by agencies with possible commercial interests in their results.A meta-analysis of 86 independent comparisons from 58 studies (6603 participants) found a small to moderate effect of portion, package, individual unit or tableware size on consumption of food (SMD 0.38, 95% CI 0.29 to 0.46), providing moderate quality evidence that exposure to larger sizes increased quantities of food consumed among children (SMD 0.21, 95% CI 0.10 to 0.31) and adults (SMD 0.46, 95% CI 0.40 to 0.52). The size of this effect suggests that, if sustained reductions in exposure to larger-sized food portions, packages and tableware could be achieved across the whole diet, this could reduce average daily energy consumed from food by between 144 and 228 kcal (8.5% to 13.5% from a baseline of 1689 kcal) among UK children and adults. A meta-analysis of six independent comparisons from three studies (108 participants) found low quality evidence for no difference in the effect of cigarette length on consumption (SMD 0.25, 95% CI -0.14 to 0.65).One included study (50 participants) estimated a large effect on consumption of exposure to differently shaped tableware (SMD 1.17, 95% CI 0.57 to 1.78), rated as very low quality evidence that exposure to shorter, wider bottles (versus taller, narrower bottles) increased quantities of water consumed by young adult participants.A meta-analysis of 13 independent comparisons from 10 studies (1164 participants) found a small to moderate effect of portion or tableware size on selection of food (SMD 0.42, 95% CI 0.24 to 0.59), rated as moderate quality evidence that exposure to larger sizes increased the quantities of food people selected for subsequent consumption. This effect was present among adults (SMD 0.55, 95% CI 0.35 to 0.75) but not children (SMD 0.14, 95% CI -0.06 to 0.34).In addition, a meta-analysis of three independent comparisons from three studies (232 participants) found a very large effect of exposure to differently shaped tableware on selection of non-alcoholic beverages (SMD 1.47, 95% CI 0.52 to 2.43), rated as low quality evidence that exposure to shorter, wider (versus taller, narrower) glasses or bottles increased the quantities selected for subsequent consumption among adults (SMD 2.31, 95% CI 1.79 to 2.83) and children (SMD 1.03, 95% CI 0.41 to 1.65). AUTHORS' CONCLUSIONS: This review found that people consistently consume more food and drink when offered larger-sized portions, packages or tableware than when offered smaller-sized versions. This suggests that policies and practices that successfully reduce the size, availability and appeal of larger-sized portions, packages, individual units and tableware can contribute to meaningful reductions in the quantities of food (including non-alcoholic beverages) people select and consume in the immediate and short term. However, it is uncertain whether reducing portions at the smaller end of the size range can be as effective in reducing food consumption as reductions at the larger end of the range. We are unable to highlight clear implications for tobacco or alcohol policy due to identified gaps in the current evidence base.

Are the Recommended Dietary Allowances for Vitamins Appropriate for Elderly People?

BACKGROUND: An adequate vitamin intake is essential for a good nutritional status, especially in older women, who are more sensitive to nutritional deficiencies. The American, European and Italian Recommended Dietary Allowances (RDAs) derive mainly from studies on adults, and it is not clear whether they also apply to elderly people. Comparing the RDAs with the actual vitamin intake of a group of healthy older women could help to clarify the real needs of elderly people. OBJECTIVE: Our aim was to compare the American, European, and Italian RDAs with the actual vitamin intake of a group of healthy older women. DESIGN: This was a cross-sectional study. PARTICIPANTS: The study included 286 healthy women aged older than 65 years. MAIN OUTCOME MEASURES: For each micronutrient, the 50th percentile of the distribution of its intake was considered as the average requirement, and the corresponding calculated RDA for our sample was the average requirement×1.2, as recommended by the US Food and Nutrition Board. This calculated RDA was then compared with the American, European, and Italian RDAs. STATISTICAL ANALYSES PERFORMED: Student's t test or the Mann-Whitney test (after checking the normal distribution of the micronutrient) for continuous variables; the χ(2) test for categorical variables. RESULTS: The calculated RDA were 2,230 µg retinol equivalents for vitamin A, 2.8 µg for vitamin B-12, 0.9 mg for thiamin, 1.4 mg for riboflavin, 3.6 mg for pantothenic acid, 1.4 mg for vitamin B-6, 320 µg for folic acid, and 115 mg for vitamin C. CONCLUSIONS: Our findings suggest that the current RDAs are adequate for older women's intake of riboflavin, vitamin B-6, and folic acid, but should be raised for vitamin B-12 and for vitamin C.