Portion distortion: typical portion sizes selected by young adults

OBJECTIVE: The incidence of obesity has increased in parallel with increasing portion sizes of individually packaged and ready-to-eat prepared foods as well as foods served at restaurants. Portion distortion (perceiving large portion sizes as appropriate amounts to eat at a single eating occasion) may contribute to increasing energy intakes and expanding waistlines. The purpose of this study was to determine typical portion sizes that young adults select, how typical portion sizes compare with reference portion sizes (based in this study on the Nutrition Labeling and Education Act's quantities of food customarily eaten per eating occasion), and whether the size of typical portions has changed over time. SUBJECTS: Young adults (n=177, 75% female, age range 16 to 26 years) at a major northeastern university. METHODS: Participants served themselves typical portion sizes of eight foods at breakfast (n=63) or six foods at lunch or dinner (n=62, n=52, respectively). Typical portion-size selections were unobtrusively weighed. A unit score was calculated by awarding 1 point for each food with a typical portion size that was within 25% larger or smaller than the reference portion; larger or smaller portions were given 0 points. Thus, each participant's unit score could range from 0 to 8 at breakfast or 0 to 6 at lunch and dinner. Analysis of variance or t tests were used to determine whether typical and reference portion sizes differed, and whether typical portion sizes changed over time. RESULTS: Mean unit scores (+/-standard deviation) were 3.63+/-1.27 and 1.89+/-1.14, for breakfast and lunch/dinner, respectively, indicating little agreement between typical and reference portion sizes. Typical portions sizes in this study tended to be significantly different from those selected by young adults in a similar study conducted 2 decades ago. CONCLUSIONS: Portion distortion seems to affect the portion sizes selected by young adults for some foods. This phenomenon has the potential to hinder weight loss, weight maintenance, and/or health improvement efforts. Thus, to ensure more effective nutrition counseling, food and nutrition professionals must develop ways to "undistort" what clients perceive to be typical portion sizes and help them recognize what is an appropriate amount to eat at a single eating occasion.     

Find your balance – the challenges of developing portion size guidance for the public

Portion size of foods and drinks is likely to be an important factor in helping people to control their weight. The British Nutrition Foundation (BNF) undertook work, with input from an Expert Panel of academics, to develop portion size guidance for healthy adults to complement the UK Eatwell Guide. A Working Group from the food industry provided funding and input on issues related to their sector. To inform the development of the portion size guide, information on portion sizes provided in food‐based dietary guidance from selected countries was reviewed as well as the methods used to develop the guidance. Portion sizes for a range of foods from the main food groups of the Eatwell Guide (excluding fruit and vegetables) were developed with reference to consumption data from the UK National Diet and Nutrition Survey and portion sizes available in major supermarkets. These were tested within different dietary patterns (e.g. omnivorous vs. vegetarian) for their ability to meet current UK food and nutrient‐based recommendations. Views on portion size and design concepts for the guidance were then explored in consumer focus groups. The final Find your balance resources were published in January 2019, with a large amount of associated media coverage and over 58 000 downloads from the BNF website in the 6 months following publication.     

Food portion weights in primary and secondary school lunches in England.

BACKGROUND: National Nutritional Standards for school lunches were reintroduced in 2001, and included guidance on portion sizes for primary schools. For the first time since 1997, nationally representative data on school food portion sizes in England have been collected using direct assessment rather than reported portion sizes. METHODS: Food portions were weighed directly in foods served in nationally representative samples of primary and secondary school meals. Results were grouped by food or food group. RESULTS: The number of portions weighed was 7975 in primary schools and 3354 in secondary schools. Individual portion weights were grouped by food or food group to yield mean, median, SD and inter-quartile range. For a given food or food group, the number of portions weighed varied from 5 to 210 portions in primary schools and between 5 and 194 portions in secondary schools. CONCLUSIONS: The results provide a good representation of typical portion weights for different foods and food groups in primary and secondary schools in England. Portion size is one factor that determines nutrient intake. New standards for school lunches are both nutrient and food-based. Guidance on portion weights will help to ensure that pupils consume the correct balance of foods to obtain the recommended nutrient intake. The present findings complement and extend existing guidance on portion sizes for pupils in schools in England and Scotland.     

Associations between the portion sizes of food groups consumed and measures of adiposity in the British National Diet and Nutrition Survey

The objective of the present study was to examine the associations between the portion sizes of food groups consumed with measures of adiposity using data from the National Diet and Nutrition Survey of British adults. Seven-day weighed dietary records, physical activity diaries and anthropometric measurements were used. Foods eaten were assigned to thirty different food groups and analyses were undertaken separately for men and women. The median daily portion size of each food group consumed was calculated. The potential mis-reporting [corrected] of dietary energy intake (EI) was identified using the following equation: EI--estimated energy requirements/EER [corrected] x 100 = percentage of under-reporting (UR) of energy needs. Multinomial logistic regression (adjusted for age, social class, physical activity level and UR) was used to determine the portion sizes of food groups most strongly associated with obesity status. Few positive associations between the portion sizes of food groups consumed and obesity status were found. However, UR was prevalent, with a median UR of predicted energy needs of 34 and 33 % in men and women, respectively. After the adjustment was made for UR, more associations between the food groups and obesity status became apparent in both sexes. The present study suggests that the true effect of increased portion size of foods on obesity status may be masked by high levels of UR. Alternatively, these data may indicate that an increased risk of obesity is not associated with specific foods/food groups but rather with an overall increase in the range of foods and food groups being consumed.     

Development of a Digital Photographic Food Atlas as a Portion Size Estimation Aid in Japan

This study aimed to develop a digital photographic food atlas as a portion size estimation aid. Commonly consumed foods were identified from the 5512-day weighed dietary records of 644 Japanese adults. Portion sizes were determined based on the market research and distribution of food consumption in the dietary records. Each food item was classified into one of two photo types: a series of photographs showing gradually increasing portion sizes or guide photographs representing a range of portion sizes and food varieties in one photograph. Photographs of the food were taken at an angle of 42°, along with appropriate reference objects such as chopsticks. In total, 209 food and dish items were included in the food atlas. Series of photographs were taken for 105 items that are not usually served in predetermined amounts (e.g., rice and pasta), whereas guide photographs were taken for 104 items usually served in predetermined amounts (e.g., bananas and cookies). Moreover, photographs were taken for 12 kinds of household measurement items, such as cups and glasses. The food atlas could be a valuable tool for estimating the portion size in dietary surveys. Evaluating the validity of this food atlas for portion size estimation is warranted.     

Portion sizes of foods frequently consumed by the Korean elderly: Data from KNHANES IV-2

The purpose of this study was to define a one-portion size of food frequently consumed by the Koreans aged 65 years or over. From the original 8,631 people who took part in the Forth Korea National Health and Nutrition Examination Survey (KNHANES IV-2) 2008, we analyzed the data on 1,458 persons (16.9%) aged 65 and over, and selected food items consumed based on the intake frequency of 30 or more by all participant. A total of 158 varieties of food items were selected. The portion size of food items was set on the basis of the median amount (50 percentile) in a single intake by a single person. In the cereals category, 13 items were selected, of which the most frequently consumed item was well-polished rice with portion size of 75 g. Among legumes, 7 items were selected, of which the most frequent item was dried black soybean with a portion size of 6 g. Among the 16 groups, the most varied food group (49 items) was vegetables, and among these the most frequently occurring item was garlic (5 g), while among the fruit group, only 11 items were selected, as their intake frequency was low. Fish and shellfish were more frequently consumed by the elderly than meats. The most frequently consumed meat was pork loin, with a portion size of 30 g. In fish and shellfish, the most frequently consumed item was dried and boiled large anchovy with a portion size of 2 g. Portion sizes for food items consumed regularly by the elderly may be conveniently and effectively used in dietary planning and in nutritional education programs, and in assessing the diet intake status of the elderly.     

Portion size of common foods predicts energy intake among preschool-aged children

This study evaluated the relationship of food intake behaviors to total energy intake among children aged 2 to 5 years old (N=5447) who participated in the Continuing Survey of Food Intakes by Individuals, 1994-1996, 1998 (CSFII 94-96, 98). Food intake behaviors examined were portion size for 10 commonly eaten foods, number of eating occasions per day, and number of foods consumed per day. Using regression models, we examined these eating behaviors as predictors of energy intakes with adjustment for body weight. Eating behaviors and body weight were positively related to energy intake, together explaining 38% to 39% of the variability. Portion size alone accounted for 17% to 19% of the variance in energy intake, whereas body weight predicted only 4%. Feeding recommendations should highlight the importance of age-appropriate portion sizes and provide guidance on the frequency of eating and number of foods consumed.     

Estimation of food portion size using photographs: validity, strengths, weaknesses and recommendations

Photographs are valuable aids in the estimation of food portion sizes and are easy to use in dietary surveys. As with other methods, employing photographs to estimate portion sizes consumed produces errors due to the method itself and errors from other sources such as poor recall of amounts actually eaten. This study was aimed at the first type of error and investigated errors due to the visual perception of food portions from food photographs in the absence of recall biases. Two hundred and seventy women were presented with various amounts of foods and asked to indicate the portion sizes using appropriate sets of photographs. The photographs showed three portion sizes (small, medium, large) for each of 45 foods commonly found in the French diet. The portions of real food estimated by subjects were prepared to the same weights as the portions photographed. Estimates of portion sizes were compared to the weighed amounts. They were found to be accurate within 25% in most cases. Except for three foods, errors on estimates were seen for one or more portions per food. Two patterns of errors were identified. For 22 foods, the small portion sizes were overestimated and the large portion sizes underestimated, but no error occurred with the medium portion. For 20 other foods, the three portion sizes were either all underestimated or all overestimated. The first pattern of error may be due to a general tendency to avoid extreme response categories, while the second pattern of error may be related to biased visual perception. In general, there was no obvious way to link the patterns of errors with the type or physical appearance of the foods. In conclusion, the photograph method is recommended for the assessment of portion sizes, provided that great care is taken to suggest the volume of the food portions in the photographs and in selecting a range of portions which encompasses the range of amounts of food actually consumed in the diet.     

Foods, nutrients and portions consumed by a sample of Australian children aged 16–24 months

Aim:  To describe the diet of a sample of Australian children aged 16–24 months with regard to the amounts of foods and nutrients consumed.
Methods:  Cross-sectional data collected from participants in a five-year randomised trial of the primary prevention of asthma. Pregnant women with a family history of atopy were recruited from six hospital antenatal clinics in western Sydney. At the 18-month assessment, carers of 429 of children completed three-day weighed food records. Three-day average intakes of foods and nutrients and average portions per eating occasion for commonly consumed foods. T -tests for comparing gender differences.
Results:  Diets were characterised by large amounts of milk and non-milk drinks with smaller amounts of cereals, fruits, vegetables and meats. Total energy intake was significantly higher for boys than girls and exceeded estimated energy requirements in both boys and girls. Food groups contributing most to energy included milk and milk products (35%), cereals (15%), cereal-based products (9%) and non-milk drinks (8%). Micronutrient intakes were below the Estimated Average Requirement in more than 5% of the children for vitamin A, calcium, vitamin C and iron. Sodium intakes exceeded the upper level of 1000 mg for 62% of children, while dietary fibre intake was only half the Adequate Intake of 14 g. Relatively few foods were widely consumed and median portion sizes were typically small in relation to commonly used reference portion sizes.
Conclusion:  These data may be useful as a preliminary basis for developing age-specific dietary surveillance tools and dietary guidance for children aged one to two years.     

Accuracy of food photographs for quantifying food servings in a lunch meal setting among Danish children and adults

Background

Visual aids, such as food photographs, are widely used in estimating food quantities in dietary surveys. The present study aimed to assess how accurately Danish adults and children can estimate food portion sizes using 37 series of photographs illustrating four to six different portion sizes under real‐life conditions; determine whether adults were more accurate than children; and estimate the error caused by using portion size photographs to estimate weights of foods consumed in macronutrient calculation.

Methods

Six hundred and twenty‐two adults and 109 children were recruited in three workplace canteens and in two schools, respectively, to estimate their lunchtime portions based on photographs. Participants were instructed to keep the foods separated on their plate when taking lunch. Participants thereafter estimated their own portions by looking at the relevant series of photographs. The actual food portions were then weighed.

Results

The proportion of correct estimations was 42% overall (range 19–77%). The mean difference (%) between estimated and actual weight was 17% (range 1–111%). Small portion size photographs were more often used correctly compared to larger portion photographs. Children had as many correct estimations as adults, although they overestimated portions more. Participants using fractions of (or more than) one photograph to estimate the portion of a food had significantly larger errors. When calculating the macronutrient content of a weekly menu using the estimated portion sizes, protein had the largest error (29%).

Conclusions

When used in a real‐life situation, the portion size photographs validated in the present study showed a certain inaccuracy compared to the actual weights.     

Gender differences in dietary intake among adults of Hindu communities in lowland Nepal: assessment of portion sizes and food consumption frequencies

OBJECTIVE: To elucidate gender differences in dietary intake among adults in lowland Nepalese communities. SUBJECTS AND METHODS: For 122 male and 195 female subjects aged 20 years and over from 94 randomly selected households, interviews using a 19-item food frequency questionnaire were conducted. To determine the portion sizes of these foods, the samples consumed by 56 subjects in a full 1-day period were weighed. Energy expenditure was estimated by time spent on daily activities. RESULTS: Gender differences in per-day energy and protein intakes were related to sex differences in body size and energy expenditure. Apparent gender differences in the crude intakes disappeared when they were expressed by nutrient density (mg or microg/MJ) since micronutrient intakes were significantly correlated with energy intake. However, males' iron intake was larger even after adjustment for energy intake, attributing to their larger portion sizes of commonly consumed staple foods and higher frequencies of consuming luxury foods (fish and tea). CONCLUSION: The intrahousehold unequal distribution of food incurs risk of iron deficiency among female subjects. SPONSORSHIP: This study was financially supported by the Ajinomoto Foundation for Dietary Culture and the Alliance for Global Sustainability Program.     

Consumption of 'extra' foods by Australian children: types, quantities and contribution to energy and nutrient intakes

OBJECTIVE: To measure the types and quantities of energy-dense, nutrient-poor 'extra' foods consumed by Australian children and adolescents and their contribution to total energy and nutrient intakes. DESIGN, SETTING AND SUBJECTS: We used data from 3007 children, aged 2-18 years, who participated in the nationally representative 1995 National Nutrition Survey. Intake was determined by 24-h recall and 'extra' foods were defined using principles outlined in the Australian Guide to Healthy Eating (AGHE) and by applying cut points for maximum amounts of fat and sugar within each food category. RESULTS: All children (99.8%) consumed at least one 'extra' food and the most commonly consumed were margarine, sugar-sweetened soft drinks, cordials and sugar. 'Extra' foods contributed 41% of daily energy intake. Those foods contributing most to energy intake were fried potatoes (4.2%), sugar-sweetened soft drinks (3.3%), ice cream/ice confection (3.1%) and cordials (2.7%). Age and sex were important determinants of 'extra' food intake, with males and older children generally consuming more and different types of, 'extra' foods than females and younger children. 'Extra' foods contributed 19% protein, 47% total fat, 47% saturated fat, 54% sugar, and approximately 20-25% of selected micronutrients to the diet. Calcium and zinc intakes from core foods were below 70% of the recommended dietary intakes for adolescent girls. CONCLUSIONS: 'Extra' foods are over-consumed at two to four times the recommended limits and contribute excessively to the energy, fat and sugar intakes of Australian children, while providing relatively few micronutrients. This is of concern in terms of children's weight and nutrient status.     

Monitoring consumption of 'extra' foods in the Australian diet: Comparing two sets of criteria for classifying foods as 'extras'

Aim: To compare two systems which classify energy‐dense, nutrient‐poor ‘extra’ foods which can be used to monitor the contribution of these foods in the diets of Australian children. The aim is to develop consistent criteria that may be used to monitor trends in the consumption of ‘extra’ foods in dietary surveys and, for research purposes, to examine associations between ‘extra’ food consumption and weight gain. Methods: The intake of ‘extra’ foods was investigated among 2‐ to 18‐year‐old children (n = 3007) who participated in the 1995 National Nutrition Survey. Two classification systems were used, both based on the Australian Guide to Healthy Eating: a simple food grouping system, and a more complex system based on specific fat and sugar cut‐points applied to food subgroups. Results: Both classification systems resulted in similar lists of commonly consumed ‘extra’ foods, and showed similar estimates for energy contribution from ‘extra’ foods, 41–42%, and similar, relatively low, contributions of micronutrients, 20–25%. Conclusion: A relatively simple food grouping classification system may be useful to estimate total energy and nutrient intake from ‘extra’ foods. However, for more detailed food‐specific analyses, a food criteria system based on cut‐points may be preferred. Nationally consistent criteria are needed for classifying ‘extra’ foods for both monitoring and research purposes, to enable comparisons of dietary data from surveys over time, and to investigate associations between ‘extra’ food consumption and nutrition outcomes such as weight gain and body mass index.     

Income differences in food consumption in the 1995 Australian National Nutrition Survey

OBJECTIVE: To assess the relationships between an index of per capita income and the intake of a variety of individual foods as well as groups of food for men and women in different age groups. DESIGN: Cross-sectional national survey of free-living men and women. SUBJECTS: A sample of 5053 males and 5701 females aged 18 y and over who completed the Australian National Nutrition Survey 1995. METHODS: Information about the frequency of consumption of 88 food items was obtained. On the basis of scores on the Food Frequency Questionnaire, regular and irregular consumers of single foods were identified. The relationships between regularity of consumption of individual foods and per capita income were analysed via contingency tables. Food variety scores were derived by assigning individual foods to conventional food group taxonomies, and then summing up the dichotomised intake scores for individual foods within each food group. Two-way ANOVA (income x age group) were performed on the food variety scores for males and females, respectively. RESULTS: Per capita income was extensively related to the reported consumption of individual foods and to total and food group variety indices. Generally, both men and women in low income households had less varied diets than those in higher-income households. However, several traditional foods were consumed less often by young high-income respondents, especially young women. CONCLUSIONS: Major income differentials in food variety occur in Australia but they are moderated by age and gender. Younger high-income women, in particular, appear to have rejected a number of traditional foods, possibly on the basis of health beliefs. The findings also suggest that data aggregation has marked effects on income and food consumption relationships.     

Food group consumption reported by the elderly during the NHANES I epidemiologic followup study

Food group consumption in the elderly (65 years of age or older) was examined using data from the food frequency questionnaire administered as part of the 1982–84 National Health and Nutrition Examination Survey's (NHANES I) Epidemiologic Followup Study (NHEFS). The number of daily servings from each food group was determined for each individual by adjusting reported frequency of consumption of food from that group (daily, weekly, monthly, yearly, and never) to a daily basis. Mean daily servings for the population of 2653 elderly were calculated for 95 NHEFS food groups combined into 32 nutritionally similar food groups, and six food groups used for current dietary guidance. Older adults reported mean daily servings greater than 1.0 for five of the 32 groups: coffee/tea, vegetable fats, non-citrus fruits, citrus fruits, and refined grains. A comparison of actual servings consumed daily with the recommended servings of six food groups indicated too few servings of dairy and grain products and adequate servings of fruits, vegetables, and protein foods. These results may be used to design nutrition education programs targeted to the elderly population.     

Food portion patterns and trends among U.S. children and the relationship to total eating occasion size, 1977-2006

Food and beverage portion sizes are related to childhood obesity. We examined trends in food portion sizes and the association with total meal sizes among U.S. children. We selected children 2- to 18-y-old (n = 31,337) from 4 nationally representative surveys of food intake between 1977-1978 and 2003-2006. We assessed portion sizes (kcal and g) of selected key foods (soft/fruit drinks, salty snacks, desserts, French fries, burgers, pizzas, Mexican fast foods, and hot dogs), the total energy from eating occasions that included key foods, and portion sizes of the selected key foods by source (stores, restaurants, and fast-food locations). These foods represented over one-third of children's energy intake in 2003-2006. Portion sizes increased significantly over the 30-y period and increases in pizza were particularly pronounced in the last decade [+176 kcal (736 kJ). Energy from eating occasions including pizzas and soft drinks increased, as did the proportion of energy from these foods in an eating occasion. Hamburgers and cheeseburgers increased in portion size and eating occasion size, but the proportion of these foods in the total eating occasions did not increase. Portion sizes of other key foods increased, although the total energy from eating events that included them remained constant (e.g. Mexican fast-foods, French fries, fruit drinks) or decreased (e.g. salty snacks, desserts). Portion sizes increased across all food sources (stores, restaurants, and fast foods) for soft drinks and pizzas but only at fast-food locations for French fries. Portion sizes continue to grow for selected foods. Fast-food chains appear to be linked with less healthful portion size increases for selected foods.     

Does Food Intake of Australian Toddlers 12–24 Months Align with Recommendations: Findings from the Australian Feeding Infants and Toddlers Study (OzFITS) 2021

(1) Background: Food-based dietary guidelines promote population health and well-being through dietary patterns that reduce chronic disease risk while providing adequate energy and nutrients. In Australia, recommended dietary patterns based on servings per day from the five food groups—fruits, vegetables, cereals and grains, meats and alternatives, and dairy—have been developed for toddlers 1–2 years of age. However, no study has assessed the intake of the five food groups in this age group nationally. (2) Aim: To compare daily servings and the percentage of energy from the five food groups and discretionary foods in toddlers 1–2 years old to the Australian Dietary Guidelines. (3) Methods: Dietary intake was assessed using a one-day food record for 475 toddlers. (4) Results: Apart from fruit and dairy, servings of the five food groups were below the recommendations. Two-thirds of toddlers did not consume enough vegetables, and only 10% consumed the recommended number of servings for cereals and grains. On average, toddlers consumed only half the recommended servings of meat and alternatives. Nearly all toddlers (89%) consumed discretionary foods, which accounted for ~12% of total energy. Forty-five percent of toddlers received breastmilk. On average, breastfed toddlers consumed fewer servings from the five food groups than non-breastfed toddlers. Dairy contributed 20% of daily energy in all toddlers; however, this food group accounted for 13% in breastfed and 32% in non-breastfed toddlers on the day of the food record. (4) Conclusions: Compared to the recommendations, alignment with the servings of the five food group foods was not achieved by most toddlers, except for fruit and dairy. Discretionary foods may have displaced nutritious family foods. Consistent with Australian Infant Feeding Guidelines, many toddlers in this study continued to receive breastmilk but the recommended dietary patterns do not include breastmilk. Dietary modeling, including breastmilk as the primary milk source, is urgently needed, along with practical advice on incorporating breastmilk in a toddler’s diet while optimizing food consumption.     

What are the key food groups to target for preventing obesity and improving nutrition in schools?

OBJECTIVE: To determine differences in the contribution of foods and beverages to energy consumed in and out of school, and to compare consumption patterns between school canteen users and noncanteen users. DESIGN: Cross-sectional National Nutrition Survey, 1995. SETTING: Australia. SUBJECTS ON SCHOOL DAYS: A total of 1656 children aged 5-15 y who had weekday 24-h dietary recall data. RESULTS: An average of 37% of total energy intake was consumed at school. Energy-dense foods and beverages such as fat spreads, packaged snacks, biscuits and fruit/cordial drinks made a greater contribution to energy intake at school compared to out of school (P< or =0.01). Fast foods and soft drinks contributed 11 and 3% of total energy intake; however, these food groups were mostly consumed out of school. Fruit intake was low and consumption was greater in school. In all, 14% of children purchased food from the canteen and they obtained more energy from fast food, packaged snacks, desserts, milk and confectionary (P< or =0.05) than noncanteen users. CONCLUSIONS:: Energy-dense foods and beverages are over-represented in the Australian school environment. To help prevent obesity and improve nutrition in schools, biscuits, snack bars and fruit/cordial drinks brought from home and fast food, packaged snacks, and confectionary sold at canteens should be replaced with fruit and water.