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

Identification of nutrition factors in the metabolic syndrome and its progression over time in older adults: analysis of the TUDA cohort

BACKGROUND

Nutrition is recognized as playing an important role in the metabolic syndrome (MetS), but the dietary components involved are unclear. We aimed to investigate nutrition factors in relation to MetS and its progression in older adults over a follow-up period of 5.4 years.

METHODS

Community-dwelling adults (≥ 60y) from the Trinity-Ulster-Department-of-Agriculture study, sampled at baseline (2008-12) and follow-up (2014-18; n 953), were classified as 'with MetS' by having three or more of: waist circumference (≥ 102 cm, males; ≥ 88 cm, females); HDL-cholesterol (< 1.0 mmol/L, males; < 1.3 mmol/L, females); triglycerides (≥ 1.7 mmol/L); blood pressure (systolic ≥ 130 and/or diastolic ≥ 85 mmHg); and hemoglobin A1c (≥ 39 mmol/mol).

RESULTS

MetS was identified in 67% of participants, increasing to 74% at follow-up. Predictors at baseline for the development of metabolic syndrome (MetS) at follow-up were higher waist circumference (odds ratio [95%CI]; 1.06 [1.01-1.11]), but not BMI, and increased triglyceride concentrations (2.01 [1.29-3.16]). In dietary analysis (at follow-up), higher protein (g/kg bodyweight/day) and monounsaturated fatty acid (g/day) intakes were each associated with lower risk of MetS (0.06 [0.02-0.20] and 0.88 [0.78-1.00], respectively), whilst higher protein was also associated with lower abdominal obesity (0.10 [0.02-0.51]) and hypertension (0.22 [0.00-0.80]). Furthermore, participants with, compared to without, MetS consumed less high-quality protein foods (P = 0.006) and more low-quality protein foods (P < 0.001), as defined by the protein digestibility-corrected amino acid score.

CONCLUSIONS

Dietary interventions targeting protein quantity and quality may have specific benefits in preventing or delaying the progression of MetS in at-risk older people, but this requires investigation in the form of randomized trials.

The effect of discretionary snack consumption on overall energy intake, weight status, and diet quality: A systematic review

The consumption frequency and portion size of discretionary snacks are thought to contribute to a greater food intake and risk of overweight or obesity in the developed world but evidence from epidemiological studies is inconclusive. To investigate this, we systematically evaluated evidence on the effects of discretionary snack consumption on weight status, energy intake, and diet quality. Articles involving discretionary snacks reported against the outcome measures of any primary, peer-reviewed study using human participants from free-living conditions for all age groups were included. A total of 14,780 titles were identified and 40 eligible publications were identified. Three key outcomes were reported: weight status (n = 35), energy intake (n = 11), and diet quality (n = 3). Increased discretionary snack consumption may contribute modestly to energy intake, however, there is a lack of consistent associations with increased weight/BMI. Although cross-sectional analyses offered conflicting findings, longitudinal studies in adults showed a consistent positive relationship between discretionary snack intake and increasing weight or body mass index. Given that experimental findings suggest reducing the size of discretionary snacks could lead to decreased consumption and subsequent energy intake, food policy makers and manufacturers may find it valuable to consider altering the portion and/or packaging size of discretionary snacks.

Child food portion sizes in the home environment: how do parents decide?

The consumption of larger portion sizes (PS) of food has been implicated in the increased prevalence of childhood obesity. The home is usually the first place children learn about food, however, little is known about how parents determine child PS in the home environment. This narrative review aimed to explore parental beliefs, decisions, strategies and barriers to the provision of appropriate food PS for children in the home environment. Results indicate that parental decisions on child food PS are based on the amounts they serve themselves, personal intuition and knowledge of child appetite. Owing to the habitual nature of food provision, parental decisions on child PS may be taken without conscious thought and/or could be part of a complex decision-making process influenced by several interlinked factors, including parental childhood mealtime experiences, other family members and child weight status. Strategies to determine child-appropriate PS include modelling the desired PS behaviour, use of unit-based food packaging and PS estimation aids, and providing the child with a degree of autonomy to rely on their own appetite cues. A lack of knowledge/awareness of PS guidance is a key barrier identified by parents to the provision of age-appropriate PS, warranting the inclusion of salient child-appropriate PS guidance within national dietary recommendations. Further home-based interventions to improve the provision of appropriate child PS are required, leveraged on parental strategies already in use, as outlined in this review.

Association of dietary flavan-3-ol intakes with plasma phenyl-γ-valerolactones: analysis from the TUDA cohort of healthy older adults

BACKGROUND

Dietary polyphenols, including flavan-3-ols (F3O), are associated with better health outcomes. The relationship of plasma phenyl-γ-valerolactones (PVLs), the products of colonic bacterial metabolism of F3O, with dietary intakes is unclear.

OBJECTIVES

To investigate whether plasma PVLs are associated with self-reported intakes of total F3O and procyanidins+(epi)catechins.

DESIGN

We measured 9 PVLs by uHPLC-MS-MS in plasma from adults (>60y) in the Trinity-Ulster-Department of Agriculture (TUDA study (2008 to 2012; n=5186) and a follow-up subset (2014 to 2018) with corresponding dietary data (n=557). Dietary (poly)phenols collected by FFQ were analyzed using Phenol-Explorer.

RESULTS

Mean (95% confidence interval [CI]) intakes were estimated as 2283 (2213, 2352) mg/d for total (poly)phenols, 674 (648, 701) for total F3O, and 152 (146, 158) for procyanidins+(epi)catechins. Two PVL metabolites were detected in plasma from the majority of participants, 5-(hydroxyphenyl)-γ-VL-sulfate (PVL1) and 5-(4'-hydroxyphenyl)-γ-VL-3'-glucuronide (PVL2). The 7 other PVLs were detectable only in 1-32% of samples. Self-reported intakes (mg/d) of F3O (r = 0.113, P = 0.017) and procyanidin+(epi)catechin (r = 0.122, P = 0.010) showed statistically significant correlations with the sum of PVL1 and PVL 2 (PVL1+2). With increasing intake quartiles (Q1-Q4), mean (95% CI) PVL1+2 increased; from 28.3 (20.8, 35.9) nmol/L in Q1 to 45.2 (37.2, 53.2) nmol/L in Q4; P = 0.025, for dietary F3O, and from 27.4 (19.1, 35.8) nmol/L in Q1 to 46.5 (38.2, 54.9) nmol/L in Q4; P = 0.020, for procyanidins+(epi)catechins.

CONCLUSIONS

Of 9 PVL metabolites investigated, 2 were detected in most samples and were weakly associated with intakes of total F3O and procyanidins+(epi)catechins. Future controlled feeding studies are required to validate plasma PVLs as biomarkers of these dietary polyphenols.

Energy Intake Evaluation by a Learning Approach Using the Number of Food Portions and Body Weight

An accurate quantification of energy intake is critical; however, under-reporting is frequent. The aim of this study was to develop an indirect statistical method of the total energy intake estimation based on gender, weight, and the number of portions. The energy intake prediction was developed and evaluated for validity using energy expenditure. Subjects with various BMIs were recruited and assigned either in the training or the test group. The mean energy provided by a portion was evaluated by linear regression models from the training group. The absolute values of the error between the energy intake estimation and the energy expenditure measurement were calculated for each subject, by subgroup and for the whole group. The performance of the models was determined using the test dataset. As the number of portions is the only variable used in the model, the error was 26.5%. After adding body weight in the model, the error decreased to 8.8% and 10.8% for the normal-weight women and men, respectively, and 11.7% and 12.8% for the overweight women and men, respectively. The results prove that a statistical approach and knowledge of the usual number of portions and body weight is effective and sufficient to obtain a precise evaluation of energy intake after a simple and brief enquiry.

Association Between Dietary Intake and Serum Uric Acid Levels in Kidney Transplant Patients

OBJECTIVES

The aim of this study was to evaluate the association between dietary intake and uric acid (UA) levels in kidney transplant patients (KTPs).

METHODS

A cross-sectional study was performed with 113 KTPs. Dietary intake assessment was carried out thorough two 24-hour dietary recalls using the 5-step multiple pass method. We evaluated the intake of energy, carbohydrate, total protein, animal protein, vegetable protein, total fat, saturated fat, trans fat, monounsaturated fat, polyunsaturated fat, omega-3 and omega-6 fatty acids, cholesterol, total sugar, added sugars, total fiber, insoluble fiber, soluble fiber, alcohol, caffeine, fructose, glucose, lactose, sucrose, vitamin A, vitamin C, vitamin E, and calcium. The intake of several food groups (portions) was also evaluated. Hyperuricemia was classified as >7.0 and >6 mg/dL for men and women, respectively.

RESULTS

In odds ratio analyses, the individuals who ingested more vegetable protein (g/kg) and caffeine (mg) presented lower chance to have hyperuricemia. In linear regression, animal protein (g) intake was positively associated (β = 0.011, P = .048), while vegetable protein (g/kg) intake was inversely associated (β = -2.45, P = .047) with serum UA. However, after a multiple linear regression including vegetable and animal protein intakes together, only vegetable protein intake remained associated with UA. The intake of other nutrients and portions of food groups was not associated with UA. All the analyses were adjusted for sex, age, hypertension, body mass index, glomerular filtration rate, use of medicines, and caloric intake misreporting.

CONCLUSIONS

Vegetable protein and caffeine intakes were inversely associated with UA in KTPs.

Do you think that you eat more than you should? Perception of adolescents from a Brazilian municipality

OBJECTIVES

To estimate the prevalence of the perception of eating more than one should and the associated factors in adolescents, and to analyze differences in dietary indicators according to the perception of overeating.

METHODS

This is a cross-sectional population-based study with a sample of 912 adolescents, participants of a food consumption survey conducted in 2015-2016, in Campinas, SP, Brazil.

RESULTS

The prevalence of the perception of eating more than one should was 35.0%, and higher in those who declared themselves non-white, those who had excess weight, those who had high waist circumference, those who would like to change their weight, those who did something to lose weight, and those who evaluated themselves as fat. The prevalence rates were also higher in those who perceived the quality of their diet as poor, who had higher frequencies of consumption of sweets, soft drinks, cold meats, and lower frequencies of consumption of fruits, raw vegetables, and breakfast up to three times a week. Among those who considered themselves as overeating, higher intakes of energy, carbohydrate, protein, fat, added sugar, and sodium were observed, and prevalence rates of 38.5% for overweight and 66.2% for obesity were identified.

CONCLUSION

The perception of eating more than one should was associated with unhealthy eating practices, the self-assessment of a poor quality diet, dissatisfaction with weight, and inadequate nutritional status. There is a need for further studies to investigate the application of the question "Do you think that you eat more than you should?" as a health behavior indicator.

Short-term high-fat feeding induces a reversible net decrease in synaptic AMPA receptors in the hypothalamus

Dietary obesity compromises brain function, but the effects of high-fat food on synaptic transmission in hypothalamic networks, as well as their potential reversibility, are yet to be fully characterized. We investigated the impact of high-fat feeding on a hallmark of synaptic plasticity, i.e., the expression of glutamatergic α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) that contain the subunits GluA1 and GluA2, in hypothalamic and cortical synaptoneurosomes of male rats. In the main experiment (experiment 1), three days, but not one day of high-fat diet (HFD) decreased the levels of AMPAR GluA1 and GluA2 subunits, as well as GluA1 phosphorylation at Ser845, in hypothalamus but not cortex. In experiment 2, we compared the effects of the three-day HFD with those a three-day HFD followed by four recovery days of normal chow. This experiment corroborated the suppressive effect of high-fat feeding on hypothalamic but not cortical AMPAR GluA1, GluA2, and GluA1 phosphorylation at Ser845, and indicated that the effects are reversed by normal-chow feeding. High-fat feeding generally increased energy intake, body weight, and serum concentrations of insulin, leptin, free fatty acids, and corticosterone; only the three-day HFD increased wakefulness assessed via video analysis. Results indicate a reversible down-regulation of hypothalamic glutamatergic synaptic strength in response to short-term high-fat feeding. Preceding the manifestation of obesity, this rapid change in glutamatergic neurotransmission may underlie counter-regulatory efforts to prevent excess body weight gain, and therefore, represent a new target of interventions to improve metabolic control.

Reliability and responsiveness of virtual portion size creation tasks: Influences of context, foods, and a bariatric surgical procedure

Food portion size influences energy intake and sustained high-energy intake often leads to obesity. Virtual portion creation tasks (VPCTs), in which a participant creates portions of food on a computer screen, predict intake in healthy individuals. The objective of this study was to determine whether portions created in VPCTs are stable over time (test-retest reliability) and responsive to factors known to influence food intake, such as eating contexts and food types, and to determine if virtual portions can predict weight loss. Patients with obesity scheduled for bariatric surgery (n = 29), and individuals with a normal BMI (18.5-24.9 kg/m2, controls, n = 29), were instructed to create virtual portions of eight snack foods, which varied in energy density (low and high) and taste (sweet and salty). Portions were created in response to the following eating situations, or "contexts": What they would a) eat to stay healthy (healthy), b) typically eat (typical), c) eat to feel comfortably satisfied (satisfied), d) consider the most that they could tolerate eating (maximum), and e) eat if nothing was limiting them (desired). Tasks were completed before, and 3 months after, surgery in patients, and at two visits, 3 months apart, in controls. Body weight (kg) was recorded at both visits. Virtual portions differed significantly across groups, visits, eating contexts, energy densities (low vs. high), and tastes (sweet vs. salty). Portions created by controls did not change over time, while portions created by patients decreased significantly after surgery, for all contexts except healthy. For patients, desired and healthy portions predicted 3-month weight loss. VPCTs are replicable, responsive to foods and eating contexts, and predict surgical weight loss. These tasks could be useful for individual assessment of expectations of amounts that are eaten in health and disease and for prediction of weight loss.

Dietary Patterns of Adolescents from the Chilean Growth and Obesity Cohort Study Indicate Poor Dietary Quality

Diet during adolescence can have lasting effects on nutritional status, health, and development. We hypothesized that dietary patterns with low-quality nutrition are associated with overweightness. We collected data for 882 Chilean adolescents from the Growth and Obesity Cohort Study (mean age: 12 years). Dietary intake was assessed through 24-h recalls and weight status data were obtained during clinical visits. Dietary patterns were obtained through exploratory factor analysis. Multiple logistic regression models were used to examine cross-sectional associations between dietary patterns and overweight (BMI z-score ≥ 1SD). Four dietary patterns were identified: "Breakfast/Light dinner", "Natural foods", "Western", and "Snacking". "Breakfast/Light dinner", "Western", and "Snacking" patterns provided higher energy and excess nutrients (sodium, saturated fat, and added sugar). Moreover, adolescents with higher adherence to "Western" or " Snacking" patterns (third tertile) had higher odds of being classified as overweight (OR = 1.67; 95%CI: 1.103-2.522 and OR = 1.86; 95%CI: 1.235-2.792, respectively) than those with lower adherence (first tertile). "Natural foods" pattern was also associated with overweightness (OR = 1.83; 95%CI: 1.219-2.754). These dietary patterns were associated with overconsumption of nutrients of public health concern. Three of the four main dietary patterns were associated with overweightness. These results highlight the need of prioritizing adolescents on obesity prevention strategies.

Intake of polyunsaturated fatty acids and ω-3 are protective factors for sarcopenia in kidney transplant patients

OBJECTIVES

The aim of this study was to associate dietary intake with sarcopenia and its components in kidney transplant patients (KTPs).

METHODS

A cross-sectional study was performed with 125 KTPs. Strength was evaluated by handgrip strength (HGS) and appendicular muscle mass was estimated by bioelectrical impedance. Functional capacity was assessed by 4-m walking test. Sarcopenia was diagnosed by revised European Consensus on Definition and Diagnosis (2019). Dietary assessment was carried out through two 24-h dietary recalls. It evaluated the consumption of energy (kcal), carbohydrates, protein (total and from animal and vegetable food sources), total fat, saturated fatty acids, monounsaturated fatty acids (MUFAs), polyunsaturated fatty acids (PUFAs), and ω-3 (g) and ω-6 (g).

RESULTS

Intake of ω-3 was positively associated with appendicular skeletal muscle mass index (ASMI; kg/m²). The greater intake of PUFA (g and %) and ω-3 (g) was associated with lower chance to present low ASMI and sarcopenia. None of the other dietary components evaluated in the present study were associated with ASMI and sarcopenia. Walking speed and HGS were not associated with dietary variables.

CONCLUSIONS

Intake of ω-3 and PUFAs are protective factors for sarcopenia and low muscle mass, but not for strength and functional capacity, in KTPs.

Differences in the association of diet quality with body fat distribution between men and women

Background/Objective:

As dietary intake and endocrine metabolism are vastly different by sex, we evaluated differences in the association of diet quality with body composition between men and women.

Subjects/Methods:

Close to 2,000 participants from the Multiethnic Cohort completed calibrated quantitative food frequency questionnaires at cohort entry (1993–96) and clinic visit (2013–16), from which the Healthy Eating Index (HEI-2010) was computed. Adiposity measures were obtained through DXA and MRI at clinic visit. Multivariable-adjusted mean adiposity measures were estimated by tertiles of HEI-2010 scores using general linear regression. The associations of diet quality with high visceral fat (VAT) and non-alcoholic fatty liver disease (NAFLD) were examined by logistic regression. To assess sex differences, cross-product terms with HEI-2010 were added to the models.

Results:

Mean HEI-2010 scores were higher for women than men at cohort entry (67.4 vs. 64.0) and clinic visit (73.6 vs. 71.0). Past and current diet quality was inversely associated with adiposity measures in men and women. Although interaction terms were not significant, the magnitude of the slopes and differences in adjusted means across tertiles suggested a stronger association for women than men. When comparing individuals who maintained a high vs. poor quality diet over 20 years, women but not men showed significantly lower risks for high VAT, whereas high HEI-2010 scores predicted a lower risk of NAFLD in both sexes.

Conclusions:

The inverse association of diet quality with adiposity was similar in both sexes, but diet quality appeared to have a stronger influence on VAT in women than men.

Mixed messages: Assessing interactions between portion-size and energy-density perceptions in different weight and sex groups

INTRODUCTION

Food portion size (PS) and energy density (ED) are the two primary determinants of total energy intake. While emerging neuroscientific data indicate judgments of PS and ED involve distinct brain regions, it is not understood how these judgements interact with each other to influence an individual's energy consumption. The present study investigated these cognitive interactions against body-mass-index (BMI) and sex.

METHODS

We tested 70 participants (including 34 overweight individuals) for cognitive biases when judging PS and ED, using the Garner task paradigm. Participants were asked to discriminate PS and ED, following pre-determined cognitive rules. Reaction time and correctness of their responses were recorded and analysed against the testing conditions across sexes and BMI groups.

RESULTS

We detected a significant 3-way interaction between BMI, Task, and Condition (F_{(3, 67)} = 4.1, p = 0.047, ƞ² = 0.06). Post-hoc tests suggested that, in the PS task, both weight groups experienced the Garner Interference effect introduced by variations of ED. That is, when making judgments concerning PS, participants were unable to ignore information relating to ED. Results from the ED task differed across weight groups, with only the overweight group being susceptible to the Garner Interference introduced by variations of PS. Additionally, both Sex and BMI were significant factors moderating reaction time when judging PS. Significantly longer reaction time was observed in female versus male comparisons, and for overweight versus healthy-weight participants (p < 0.05).

CONCLUSION

Overall, the results confirmed cognitive interactions involving PS and ED, although these interactions were asymmetric across BMI groups. These findings provide new insights into the cognitive processes underpinning individual dietary decision-making, and are potentially important for developing targeted intervention strategies for effective management of unhealthy eating behaviour.

Demographic, socioeconomic and lifestyle factors associated with sugar-sweetened beverage intake: a population-based study

ABSTRACT: Introduction: The intake of sugar-sweetened beverages (SSB) varies according to the characteristics of the population. Objective: To investigate the SSB intake and demographic, socioeconomic and lifestyle factors associated with its consumption in adolescents, adults, and older adults in São Paulo. Methods: Data were drawn from the Health Survey of São Paulo, a cross-sectional population-based study including 1,662 individuals aged 12 years or more. SSB were classified into six groups: sugar-sweetened sodas, sweetened coffee and tea, sweetened milk and dairy products, sweetened fruit juice, sweetened fruit drink, and total SSB. The association of each group with demographic, socioeconomic and lifestyle variables was assessed using linear regression models. Results: The mean SSB intake was 668.4 mL in adolescents, 502.6 mL in adults, and 358.2 mL in elderly adults. Sodas and sweetened coffee and tea represented had the greatest contribution to energy intake. SSB consumption was lower among female sex and higher among overweight adolescents, among sufficiently active adults, and among lower household per capita income older adults. Consumption of SSB was high, particularly among adolescents. Public policies are required in order to decrease the consumption of these beverages. Conclusion: Age group, sex, household per capita income, and body mass index status were associated with SSB intake.

Application of the ≤ 10:1 carbohydrate to fiber ratio to identify healthy grain foods and its association with cardiometabolic risk factors

PURPOSE

Optimal metrics to assess healthfulness of carbohydrate-rich products are not well established. We investigated how the content per 10 g of carbohydrate of at least 1 g of fiber (≤ 10:1-ratio) related to nutritional quality in grain foods as well as cardiometabolic risk factors in São Paulo, Brazil.

METHODS

Data were from the cross-sectional population-based study 2015 Health Survey of São Paulo, including a probabilistic sample of urban residents in the city. Participants (n = 1188) aged 20 + years completed a 24-h dietary recall and a subsample of 603 participants had blood samples, anthropometrics, and blood pressure measurements collected, and answered a second 24-h recall. Energy and nutrient contents of grain foods meeting or not meeting the ≤ 10:1-ratio were evaluated using linear regression models. The association between consumption (percent energy, %E) of grain foods meeting the ≤ 10:1-ratio and cardiometabolic risk factors were investigated using linear regression models.

RESULTS

Foods meeting the ≤ 10:1-ratio had less available carbohydrate (- 3.0 g/serving), total sugar (- 7.4 g/serving), added sugar (- 7.2 g/serving) and saturated fat (- 0.7 g/serving), and more dietary fiber (+ 3.5 g/serving), protein (+ 2.1 g/serving), potassium (+ 100.1 mg/serving), iron (+ 0.9 mg/serving), selenium (+ 4.2 µg/serving), magnesium (+ 38.7 mg/serving), and zinc (+ 1.1 mg/serving). Each increase in 1%E consumption of grain foods meeting the ≤ 10:1-ratio was associated with lower levels of blood triacylglycerol (- 10.7%), the triacylglycerol/high-density lipoprotein cholesterol ratio (- 14.9%), fasting insulin (- 13.6%), and homeostasis model assessment for insulin resistance (- 14.0%).

CONCLUSION

The ≤ 10:1-ratio identified grain foods with higher nutritional quality and higher intakes of these foods were associated with cardiometabolic risk factors related to atherogenic dyslipidemia and insulin resistance.

Portion size normality and additional within-meal food intake: two crossover laboratory experiments

Reducing food portion size could reduce energy intake. However, it is unclear at what point consumers respond to reductions by increasing intake of other foods. We predicted that a change in served portion size would only result in significant additional eating within the same meal if the resulting portion size was no longer visually perceived as 'normal'. Participants in two crossover experiments (Study 1: n 45; Study 2: n 37; adults, 51 % female) were served different-sized lunchtime portions on three occasions that were perceived by a previous sample of participants as 'large-normal', 'small-normal' and 'smaller than normal', respectively. Participants were able to serve themselves additional helpings of the same food (Study 1) or dessert items (Study 2). In Study 1 there was a small but significant increase in additional intake when participants were served the 'smaller than normal' compared with the 'small-normal' portion (m difference = 161 kJ, P = 0·002, d = 0·35), but there was no significant difference between the 'small-normal' and 'large-normal' conditions (m difference = 88 kJ, P = 0·08, d = 0·24). A similar pattern was observed in Study 2 (m difference = 149 kJ, P = 0·06, d = 0·18; m difference = 83 kJ, P = 0·26, d = 0·10). However, smaller portion sizes were each associated with a significant reduction in total meal intake. The findings provide preliminary evidence that reductions that result in portions appearing 'normal' in size may limit additional eating, but confirmatory research is needed.

Considering Gender Differences in Portion Sizes to Improve the Accuracy of Nutrient Intakes from A Food Frequency Questionnaire

The aim of this study was to examine whether using gender specific-portion size (GS-PS) improves the accuracy of nutrient intake assessment by a quantitative food frequency questionnaire (QFFQ). For GS-PS quantification, a gram amount was assigned to each PS category for each food item for men and women separately using data from three 24 h dietary recalls (24HDRs) in a calibration study of the Multiethnic Cohort (men = 1141, women = 1150). Nutrient intakes were calculated from the QFFQ using the original-PS and the GS-PS, and were compared with 24HDRs. When intakes of energy and 15 nutrients were compared, absolute intakes calculated using the GS-PS were closer to intake levels of 24HDRs in both men and women. Using GS-PS did not affect intakes expressed as nutrient density or correlations between 24HDRs and the QFFQ. The current findings indicate that considering gender in PS determination can increase the accuracy of intake assessment by QFFQ for absolute nutrient intakes, but not for nutrient densities.

Increased sugar-sweetened beverage consumption is associated with poorer dietary quality: A cross-sectional population-based study

ABSTRACT Objective To evaluate the association between sugar-sweetened beverages consumption and dietary quality in adolescents, adults, and older adults living in São Paulo, Brazil. Methods Data were drawn from a cross-sectional population-based study conducted in 2008 in a representative urban city sample involving 1494 consumers of sugar-sweetened beverages. Dietary intake was evaluated through two 24-Hour Dietary Recalls, and the usual sugar-sweetened beverages consumption was estimated using the Multiple Source Method. Dietary quality was evaluated using the Brazilian Healthy Eating Index – Revised. The association between total score of the revised index and components with sugar-sweetened beverages consumption tertiles was assessed using multiple linear regression models for each age group, considering the sample design. Results Regardless of age group, the increase of sugar-sweetened beverages consumption was associated with a decrease in the total Healthy Eating Index – Revised score and in the components “total fruit”; “whole fruit”; “meat, eggs and legumes”, and the “solid fat, alcohol and added sugar”. Conclusion The results of our study suggest that higher sugar-sweetened beverages consumption was associated with poorer dietary quality. Planning public health policies aimed at decreasing sugar-sweetened beverages consumption is essential to increase dietary quality and reduce the incidence of noncommunicable diseases.

Portion Size of Energy-Dense Foods among French and UK Adults by BMI Status

Evidence links consumed food portion size (FPS) and excess weight via increased energy intake. Policies to regulate on-pack serving sizes may be needed; determining consumed FPS of popular energy-dense foods for normal weight and overweight or obese (OWOB) adults, as reported here, may provide evidence to assist this. Data were analysed from national cross-sectional surveys, the French Étude Individuelle Nationale des Consommations Alimentaires2 2005⁻2007 (n = 2117), and UK National Diet and Nutrition Survey 2008⁻2014 (n = 3413). The impact of body mass index (BMI) on FPS is also investigated, adjusting for age, sex and under-reporting. Effects of under-reporting on relationships between FPS and BMI; and BMI on consumption frequency (UK only) were explored. OWOB reported larger FPS than normal-weight individuals in many, but not all food subgroups; however, there were only two significant FPS differences. In adjusted analyses, French individuals consumed 1.0 g (99% CI 0.01⁻2.1 p = 0.01) greater FPS in cakes for 1 point difference in BMI. 'Other cakes' and 'dark chocolate' were also significantly positively associated with BMI. High-fat bar snacks, but no UK main food groups, were positively associated with BMI. There was limited evidence of links between FPS and BMI in UK and French national cross-sectional data, possibly due to data limitations such as under-reporting. Future work should explore this and relationships between consumed FPS and on-pack suggested serving sizes to provide evidence to assist obesity-prevention policies.

Differences over 12 Years in Food Portion Size and Association with Excess Body Weight in the City of São Paulo, Brazil

Although changes in Brazilian diet have occurred over the last decades, there is no evidence about differences in food portion sizes (FPS) over time. Therefore, we aimed to evaluate the association of FPS with excess body weight (EBW), and to monitor differences in the population from São Paulo, Brazil, from 2003 to 2015. Data came from three cross-sectional population-based studies with 5270 individuals aged ≥12 years in 2003, 2008, and 2015. Dietary data were obtained from 24-h recalls. Logistic regression models were used to evaluate the association between FPS and EBW. Over the years, there was a diverse variation in FPS, with an increase in some groups (white meat, salted snacks, coffee/tea, eggs) and decrease in others (rice, red meat, sweets, pasta, sandwiches, cold cuts). The percentage of people reporting the intake of six food groupings (rice, white meat, sweets, fruits, commercial juices, toasts/biscuits) increased in the period. In this population, EBW was associated with larger FPS of 11 of the 30 food groupings investigated (cold cuts, fried snacks, fruit and commercial juices, pizza, red meat, rice, salted snacks, soft drinks, soups, sugar). These findings could support future interventions and policies for optimal food intake in Brazil.

Portion Sizes from 24-Hour Dietary Recalls Differed by Sex among Those Who Selected the Same Portion Size Category on a Food Frequency Questionnaire

BACKGROUND

Accounting for sex differences in food portions may improve dietary measurement; however, this factor has not been well examined.

OBJECTIVE

The aim of this study was to examine sex differences in reported food portions from 24-hour dietary recalls (24HDRs) among those who selected the same portion size category on a quantitative food frequency questionnaire (QFFQ).

DESIGN

This study was conducted with a cross-sectional design.

PARTICIPANTS/SETTING

Participants (n=319) were members of the Hawaii-Los Angeles Multiethnic Cohort who completed three 24HDRs and a QFFQ in a calibration study conducted in 2010 and 2011.

MAIN OUTCOME MEASURES

Portions of individual foods reported from 24HDRs served as the outcome measures.

STATISTICAL ANALYSES PERFORMED

Mean food portions from 24HDRs were compared between men and women who reported the same portion size on the QFFQ, after adjustment for race/ethnicity using a linear regression model. Actual amount and the assigned amount of the selected portion size in the QFFQ were compared using one-sample t test for men and women separately.

RESULTS

Of 163 food items with portion size options listed in the QFFQ, 32 were reported in 24HDRs by ≥20 men and ≥20 women who selected the same portion size in the QFFQ. Although they chose the same portion size on the QFFQ, mean intake amounts from 24HDRs were significantly higher for men than for women for "beef/lamb/veal," "white rice," "brown/wild rice," "lettuce/tossed salad," "eggs cooked/raw," "whole wheat/rye bread," "buns/rolls," and "mayonnaise in sandwiches." For men, mean portions of 14 items from the 24HDRs were significantly different from the assigned amounts for QFFQ items (seven higher and seven lower), whereas for women, mean portions of 14 items were significantly lower from the assigned amounts (with five significantly higher).

CONCLUSIONS

These sex differences in reported 24HDR food portions-even among participants who selected the same portion size on the QFFQ-suggest that the use of methods that account for differences in the portions consumed by men and women when QFFQs are quantified may provide more accurate absolute dietary intakes.

Influence of Haem, Non-Haem, and Total Iron Intake on Metabolic Syndrome and Its Components: A Population-Based Study

Studies suggest that haem, non-haem iron and total iron intake may be related to non-communicable diseases, especially metabolic syndrome. This study was undertaken to investigate the association of haem, non-haem iron and total iron intake with metabolic syndrome and its components. A cross-sectional population-based survey was performed in 2008, enrolling 591 adults and elderly adults living in São Paulo, Brazil. Dietary intake was measured by two 24 h dietary recalls. Metabolic syndrome was defined as the presence of at least three of the following: hypertension, hyperglycaemia, dyslipidaemia and central obesity. The association between different types of dietary iron and metabolic syndrome was evaluated using multiple logistic regression. After adjustment for potential confounders, a higher haem iron intake was positively associated with metabolic syndrome and with elevated triglyceride levels. A higher total iron intake was positively associated with hyperglycaemia. Non-haem iron intake was positively associated with hyperglycaemia in the fourth quintile. In conclusion, this study suggests that the different types of dietary iron are associated with metabolic syndrome, elevated triglyceride levels and hyperglycaemia. In addition, it emphasises the importance of investigating the roles of dietary iron in health outcomes, since its consumption may have different impacts on health.

Obesity-Induced Structural and Neuronal Plasticity in the Lateral Orbitofrontal Cortex

The orbitofrontal cortex (OFC) integrates sensory information with the current value of foods and updates actions based on this information. Obese humans and rats fed a cafeteria diet have impaired devaluation of food rewards, implicating a potential obesity-induced dysfunction of the OFC. We hypothesized that obesity alters OFC pyramidal neuronal structure and function and reduces conditioned suppression of feeding. Rats were given restricted (1 h/day), extended (23 h/day) or no (chow only) access to a cafeteria diet and tested for a conditioned suppression of feeding. Golgi-cox impregnation and whole-cell patch clamp experiments were performed in lateral OFC pyramidal neurons of rats from the 3 feeding groups. Rats with 40 days of extended, but not restricted, access to a cafeteria diet became obese and continued to feed during foot shock-predicting cues. Access to a cafeteria diet induced morphological changes in basilar dendrites of lateral OFC pyramidal neurons. While there were no alterations in excitatory synaptic transmission underlying altered spine density, we observed a more depolarized resting membrane potential. This was accompanied by decreased inhibitory synaptic transmission onto lateral OFC pyramidal neurons due to decreased release probability at GABAergic inputs. These changes could underlie the inability of the OFC to encode changes in the motivation value of food that is observed in obese rodents and humans.

Dietary BCAA Intake Is Associated with Demographic, Socioeconomic and Lifestyle Factors in Residents of São Paulo, Brazil

BACKGROUND

Identifying which risk groups have a higher intake of branched chain amino acids (BCAA) is important for the planning of public policies. This study was undertaken to investigate BCAA consumption, the foods contributing to that consumption and their association with demographic, socioeconomic and lifestyle factors.

METHODS

Data from the Health Survey of São Paulo, a cross-sectional population-based survey (n = 1662; age range 12-97 years), were used. Dietary intake was measured using 24-h dietary recalls. Baseline characteristics were collected. Associations between BCAA intake and demographic, socioeconomic and lifestyle factors were determined using linear regression.

RESULTS

Total BCAA intake was 217.14 mg/kg·day (Leu: 97.16 mg/kg·day; Ile: 56.44 mg/kg·day; Val: 63.54 mg/kg·day). BCAA intake was negatively associated with female sex in adolescents and adult groups, with no white race in adolescents, and with former smoker status in adults. Conversely, BCAA was positively associated with household per capita income in adolescents and adults. No associations were observed in the older adults group. Main food contributors to BCAA were unprocessed red meat, unprocessed poultry, bread and toast, beans and rice.

CONCLUSIONS

Adolescents and adults were the most vulnerable to having their BCCA intake influenced by demographic, socioeconomic and lifestyle factors.

Dietary energy density and obesity: how consumption patterns differ by body weight status

PURPOSE

Recent public health messages have advised consumers to lower dietary energy density (ED) for weight management, but it is not known whether the proportion of the diet from low-ED foods is related to weight status. In a nationally representative sample of US adults, we evaluated whether the proportions of dietary energy intake contributed by low- and high-ED foods are associated with body mass index (BMI) and waist circumference (WC).

METHODS

Data were from a cross-sectional sample of 9551 adults ≥18 years in the 2005-2008 National Health and Nutrition Examination Survey (NHANES). ED (kcal/g) was calculated for each food item reported during a 24-h dietary recall; individual foods were divided into five ED categories: very low ED (<0.6 kcal/g), low ED (0.6-1.5 kcal/g), medium ED (1.51-2.25 kcal/g), high ED (2.26-4.0 kcal/g), and very high ED (>4.0 kcal/g). The percentages of total energy and the food weight from each category were evaluated by BMI and WC after controlling for total energy intake and other covariates.

RESULTS

Men classified as lean (BMI < 25 kg/m²) reported consuming a greater proportion of total energy from very low- and low-ED foods (7.2 %_{very low} and 23.3 %_low), compared to men considered obese ((BMI > 30 kg/m²); 5.2 %_{very low} and 20.1_low %; p-trends <0.001_{very low}, 0.002_low). Similarly, women classified as lean reported intakes of very low-ED foods of 7.8 % (vs. 6.4 % for women with obesity) of total energy and low-ED foods of 24.7 % (vs. 21.5 % for women with obesity) of total energy (p-trends 0.007_{very low}, 0.004_low). Men and women with obesity reported greater proportions of energy from high-ED foods (45.9 %_{men with obesity} vs. 42.4 %_{lean men}, 44.2 %_{women with obesity} vs. 39.9 %_{lean women}) with significant statistical trends (men = 0.008, women = 0.0005). Similar patterns were observed for intakes of proportions of very low-, low-, and high-ED foods and WC.

CONCLUSION

Higher proportions of energy intake and food weight contributed by very low- and low-ED foods are associated with lower BMI (and WC).

Portion-size preference as a function of individuals' body mass index

OBJECTIVE

Large portions of food are often blamed for rising rates of obesity. We tested the possibility that people who are heavier may tend to select or prefer larger portions than do people who are lighter.

METHODS

Participants (total N = 798) were asked to choose between a small and larger portion of pasta for a hypothetical meal (Studies 1, 2 and 4), to indicate their ideal portion from a range of portion-size options (Study 2), or to select their preferred portion size from each of 28 portion pairs (Study 3).

RESULTS

Across all studies, there were no significant differences between heavier and lighter participants in their portion-size selection (effect sizes ranged from d = -0.06 to 0.33). The pattern was the same regardless of whether we grouped participants as having a body mass index (BMI) <25 vs. ≥25, as having a BMI of <30 vs. ≥30, or treated BMI as a continuous predictor.

CONCLUSIONS

Given the lack of association between BMI and portion-size preference, we suggest that factors other than portion size, such as differences in meal frequency, food type, plate clearing or compensation at subsequent meals, may need to be considered in order to explain the increasing prevalence of obesity.

Association of Overweight with Food Portion Size among Adults of São Paulo - Brazil

BACKGROUND

Although studies show that portion size affects energy intake, few have demonstrated a link between portion size and weight status, especially in free-living populations. The objective of the present study was to assess the relationship between food portion sizes and overweight in a representative population of adults of São Paulo, Brazil.

METHODS

Cross-sectional population-based study with 1005 adults from São Paulo, Brazil. Dietary data were obtained from two 24-hour recalls. Reported foods were classified into groups and energy contribution, prevalence of consumers and portion sizes were calculated. Individuals were classified according to BMI in with and without overweight. Logistic regression models were used to evaluate the association between food portion sizes and being overweight.

RESULTS

The most consumed food groups were: beans, breads/rolls, coffee/tea, milk, rice, and sugar. Rice, red meat, breads/rolls, and white meat were the groups with the highest percentage of contribution to total energy intake. Butter/margarine, toasts/biscuits, sugar, and cakes were the groups with the highest energy density. After adjustment for confounding variables, overweight was associated with larger portions of pizza (OR = 1.052; p = 0.048), red meat (OR = 1.025; p = 0.043), rice (OR = 1.033; p<0.001), salted snacks (OR = 1.078; p = 0.022), and soft drinks (OR = 1.016; p = 0.007).

CONCLUSIONS

Larger portions of few food groups with different energy densities were associated with being overweight, suggesting that overweight may be related to the consumption of larger portion sizes of a series of food groups, not a food group alone. Additionally, we highlight the importance of considering underreporting as a confounding factor in these associations.

An Analytical Pipeline for Quantitative Characterization of Dietary Intake: Application To Assess Grape Intake

Lack of accurate dietary assessment in free-living populations requires discovery of new biomarkers reflecting food intake qualitatively and quantitatively to objectively evaluate effects of diet on health. We provide a proof-of-principle for an analytical pipeline to identify quantitative dietary biomarkers. Tartaric acid was identified by nuclear magnetic resonance spectroscopy as a dose-responsive urinary biomarker of grape intake and subsequently quantified in volunteers following a series of 4-day dietary interventions incorporating 0 g/day, 50 g/day, 100 g/day, and 150 g/day of grapes in standardized diets from a randomized controlled clinical trial. Most accurate quantitative predictions of grape intake were obtained in 24 h urine samples which have the strongest linear relationship between grape intake and tartaric acid excretion (r(2) = 0.90). This new methodological pipeline for estimating nutritional intake based on coupling dietary intake information and quantified nutritional biomarkers was developed and validated in a controlled dietary intervention study, showing that this approach can improve the accuracy of estimating nutritional intakes.

Decreasing the number of small eating occasions (<15 % of total energy intake) regardless of the time of day may be important to improve diet quality but not adiposity: a cross-sectional study in British children and adolescents

Evidence of associations between meal frequency (MF) and snack frequency (SF) and diet and obesity in young populations is limited. This cross-sectional study examined MF and SF in relation to dietary intake and adiposity measures in British children aged 4-10 years (n 818) and adolescents aged 11-18 years (n 818). Based on data from a 7-d weighed dietary record, all eating occasions were divided into meals or snacks on the basis of contribution to energy intake (≥15 or <15 %) or time (06.00-10.00, 12.00-15.00 and 18.00-21.00 hours or others). All measures of MF and SF showed positive associations with energy intake, except for MF based on energy contribution in children. Irrespective of the definition of snacks, SF was associated with higher intakes of soft drinks, confectionery and total sugar, lower intakes of cereals, fish, meat, protein, PUFA, starch and dietary fibre, and a lower diet quality (assessed by the Mediterranean diet score, except for SF based on energy contribution in adolescents). MF based on time, but not based on energy contribution, was associated with higher intakes of confectionery and total sugar, lower intakes of fish, protein, PUFA and starch, and, only in children, a lower diet quality. All measures of MF and SF showed no association with adiposity measures. In conclusion, this cross-sectional study in British children and adolescents suggests that decreasing the number of small eating occasions (<15 % of total energy intake) regardless of the time of day may be important to improve diet quality but not adiposity.

Associations between meal and snack frequency and diet quality and adiposity measures in British adults: findings from the National Diet and Nutrition Survey

Objective

To examine how different definitions of meals and snacks can affect the associations of meal frequency (MF) and snack frequency (SF) with dietary intake and adiposity measures.

Design

Based on 7 d weighed dietary record data, all eating occasions providing ≥210 kJ of energy were divided into meals or snacks based on contribution to energy intake (≥15 % or <15 %) or time (06.00–10.00, 12.00–15.00 and 18.00–21.00 hours; other). Diet quality was assessed using the Healthy Diet Indicator (HDI) and Mediterranean Diet Score (MDS).

Setting

Great Britain.

Subjects

British adults aged 19–64 years (n 1487).

Results

MF based on energy contribution was associated with higher intake of dietary fibre, lower intakes of non-milk extrinsic sugars and alcohol, and higher HDI (only men) and MDS. MF based on time was associated with higher HDI and MDS in women only. Conversely, irrespective of the definition of snacks, SF was associated with higher intakes of confectionery and alcohol, lower intakes of cereals, protein, fat and dietary fibre, and lower HDI (except for SF based on energy contribution in women) and MDS. After adjustment for potential confounders, MF based on time, but not MF based on energy contribution, was positively associated with BMI and waist circumference in men only. SF was positively associated with BMI and waist circumference, irrespective of the definition of snacks.

Conclusions

Higher SF was consistently associated with lower diet quality and higher adiposity measures, while associations with MF varied depending on the definition of meals and sex.

Personal and social norms for food portion sizes in lean and obese adults

Background

Portion size is an important component of dietary advice for weight control, but little is known about what portion sizes people consider “normal”. This study determined the effect of BMI, gender, dietary restraint, and liking of the food on personal and social portion size norms for a range of foods, and the degree of certainty over the norms.

Methods

30 lean (BMI 20-25kg/m²) and 30 obese (BMI 30-35kg/m²) men and women (aged 18-60years) viewed 17 different portion sizes of 12 foods on a computer screen on two occasions a week apart. Participants responded ‘more’ or ‘less’ to each photograph reflecting personal portion size preference or perceived portion sizes of others. Personal and social norms for portion sizes of each food were determined using the method of constant stimuli giving a sigmoidal curve of the probability of answering ‘less’ over a range of portion sizes. The slope of the sigmoid at the norm gave a measure of certainty about the norm. Regression models were used to examine the effect of BMI, gender, dietary restraint and liking of the food on personal norms, social norms, the relationship between norms, and the slopes.

Results

Personal norms were significantly larger in the obese (p=0.026), men (p<0.001), those with lower dietary restraint (p<0.001), and those with higher liking for the food (p<0.001). Social norms were larger for women (p=0.012). The slopes at the norms were 30% shallower in the obese and in men (p<0.001).

Conclusion

Larger personal norms for portion size among the obese, men, those with lower dietary restraint, and those with higher liking for a food imply greater consumption, which may undermine weight control. Shallower slopes for norms in the obese and in men may imply less clearly defined habitual portion sizes.

The Influence of Portion Size and Timing of Meals on Weight Balance and Obesity

This review focuses on the influence of portion size and temporal distribution of food intake on weight balance and obesity in adults. The inconsistency of definitions in the area of meal patterns is also discussed. The conclusion is that regular eating habits might facilitate weight balance, while unplanned snacking as well as consuming the major part of the energy intake at the end of the day seem to be unfavourable. Altogether, the research suggests that large portions promote over-consumption and, therefore, limiting portion size of energy dense foods and drinks with added sugar could be recommended. Even if more research is needed, these factors should be taken into consideration in recommendations for obesity prevention.

What is the role of portion control in weight management?

Systematic studies have shown that providing individuals with larger portions of foods and beverages leads to substantial increases in energy intake. The effect is sustained over weeks, supporting the possibility that large portions have a role in the development of obesity. The challenge is to find strategies to effectively manage the effects of portion size. One approach involves teaching people to select appropriate portions and to use tools that facilitate portion control. Although tools such as portion-control plates have been shown in several randomized trials to improve weight loss, limited data are available on whether education and tools lead to long-term changes in eating behavior and body weight. Another approach is to use preportioned foods (PPFs) to add structure to meals and minimize decisions about the amount of food to eat. A number of randomized controlled trials have demonstrated the efficacy of both liquid meal replacements and solid PPFs for weight loss and weight loss maintenance, but it is not known if they lead to better understanding of appropriate portions. Although portion control is important for weight management, urging people simply to 'eat less' of all foods may not be the best approach as high-energy-dense foods disproportionately increase energy intake compared with those lower in energy density. A more effective strategy may be to encourage people to increase the proportion of foods low in energy density in their diets while limiting portions of high-energy-dense foods. If people lower the energy density of their diet, they can eat satisfying portions while managing their body weight.

The role of metabonomics as a tool for augmenting nutritional information in epidemiological studies

Most chronic diseases have been demonstrated to have a link to nutrition. Within food and nutritional research there is a major driver to understand the relationship between diet and disease in order to improve health of individuals. However, the lack of accurate dietary intake assessment in free-living populations, makes accurate estimation of how diet is associated with disease risk difficulty. Thus, there is a pressing need to find solutions to the inaccuracy of dietary reporting. Metabolic profiling of urine or plasma can provide an unbiased approach to characterizing dietary intake and various high-throughput analytical platforms have been used in order to implement targeted and nontargeted assays in nutritional clinical trials and nutritional epidemiology studies. This review describes first the challenges presented in interpreting the relationship between diet and health within individual and epidemiological frameworks. Second, we aim to explore how metabonomics can benefit different types of nutritional studies and discuss the critical importance of selecting appropriate analytical techniques in these studies. Third, we propose a strategy capable of providing accurate assessment of food intake within an epidemiological framework in order establish accurate associations between diet and health.

Estimating food portions. Influence of unit number, meal type and energy density

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University staff/students showed poor awareness of appropriate portion sizes.

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Unit number and meal classification affected portion size estimation.

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Portion sizes in sugary drinks, pizza and pasta were underestimated by 30–46%.

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Women were better at estimating food portion sizes than men.

Estimating how much is appropriate to consume can be difficult, especially for foods presented in multiple units, those with ambiguous energy content and for snacks. This study tested the hypothesis that the number of units (single vs. multi-unit), meal type and food energy density disrupts accurate estimates of portion size. Thirty-two healthy weight men and women attended the laboratory on 3 separate occasions to assess the number of portions contained in 33 foods or beverages of varying energy density (1.7–26.8 kJ/g). Items included 12 multi-unit and 21 single unit foods; 13 were labelled “meal”, 4 “drink” and 16 “snack”. Departures in portion estimates from reference amounts were analysed with negative binomial regression. Overall participants tended to underestimate the number of portions displayed. Males showed greater errors in estimation than females (p = 0.01). Single unit foods and those labelled as ‘meal’ or ‘beverage’ were estimated with greater error than multi-unit and ‘snack’ foods (p = 0.02 and p < 0.001 respectively). The number of portions of high energy density foods was overestimated while the number of portions of beverages and medium energy density foods were underestimated by 30–46%. In conclusion, participants tended to underestimate the reference portion size for a range of food and beverages, especially single unit foods and foods of low energy density and, unexpectedly, overestimated the reference portion of high energy density items. There is a need for better consumer education of appropriate portion sizes to aid adherence to a healthy diet.

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.

Estimated portion sizes of snacks and beverages differ from reference amounts and are affected by appetite status in non-obese men

Objective

To explore the extent to which appetite status influences portion size estimation in men under laboratory conditions and to quantify how much participants’ portion estimates differed from the recommended portion sizes defined by authoritative bodies (i.e. government and health professionals’ reference amounts).

Design

Repeated, randomized cross-over trial with each participant attending the laboratory on four separate occasions. At each session, participants rated the number of portions of eight foods and beverages displayed in front of them. Participants rated portions twice after consuming breakfast (full conditions) and twice after an overnight fast (hungry conditions). Portion estimates were compared with reference amounts from the British and American Dietetic Associations, from the UK Food Standards Agency and from the US Food and Drug Administration.

Setting

Food skills laboratory, University of Chester, UK.

Subjects

Twenty-seven non-obese men (mean age 24·9 (sd 6·5) years).

Results

Portion size estimates for all items were significantly smaller under hungry than under full conditions (P < 0·01). Relative to reference instruments, estimates were significantly smaller for all foods except banana, irrespective of appetite status (P < 0·001).

Conclusions

In this data set, appetite status altered the perception of food amounts. There were large discrepancies between participants’ perception of a portion and recommendations from health professionals and government standards. Nutritional educational strategies should take into account the role of hunger along with a person's familiarity with existing portion size systems when advising on portion sizes.

Use of accelerometer data in prediction equations for capturing implausible dietary intakes in adolescents

BACKGROUND

Reporting errors have been quantified in epidemiologic studies by comparing reported intakes with predicted energy requirements (pERs). Several studies lacking measures of physical activity level (PAL) assigned low-active levels to obtain pERs.

OBJECTIVE

We applied objective physical activity measures to current methods to quantify dietary reporting errors and compared associations with anthropometric and dietary variables among plausible and implausible reporters.

DESIGN

This study included 2868 adolescents with an average age of 13 y. Three-day dietary records, accelerometers, and dual-energy X-ray absorptiometry were used to assess diet, activity, and body composition, respectively. Three variations of physical activity coefficients were used: 1) assigning low physical activity coefficients (PA(low)), 2) calculating PAL values (PA(PAL)), and 3) applying minutes of moderate-to-vigorous physical activity (PA(MVPA)).

RESULTS

Of the total participants, 51.5%, 51.8%, and 37.1% of the PA(low), PA(PAL), and PA(MVPA) groups, respectively, were classified as underreporters, and 40.8%, 37.9%, and 42.4% of the respective groups were classified as plausible reporters. Underreporters had a higher body mass index, body fat, and waist circumference than did plausible reporters (P < 0.001 for all). Overreporters had a lower weight and body fat than did plausible reporters (P < 0.001 for all). Underreporters reported lower dairy and calcium intakes than did plausible reporters; the results were attenuated with adjustment for total energy.

CONCLUSION

Accounting for objective physical activity measures to quantify reporting errors resulted in different and potentially more reasonable proportions of implausible reporters.

Trans fats in America: a review of their use, consumption, health implications, and regulation

Trans fatty acids have long been used in food manufacturing due in part to their melting point at room temperature between saturated and unsaturated fats. However, increasing epidemiologic and biochemical evidence suggest that excessive trans fats in the diet are a significant risk factor for cardiovascular events. A 2% absolute increase in energy intake from trans fat has been associated with a 23% increase in cardiovascular risk. Although Denmark has shown it is possible to all but eliminate commercial sources of trans fats from the diet, total elimination is not possible in a balanced diet due to their natural presence in dairy and meat products. Thus, the American Heart Association recommends limiting trans fats to <1% energy, and the American Dietetic Association, the Institute of Medicine, US Dietary Guidelines, and the National Cholesterol Education Project all recommend limiting dietary trans-fat intake from industrial sources as much as possible. The presence of small amounts of trans fat in hydrogenated or partially hydrogenated oils/food products will likely cause many Americans to exceed their recommended maximum. This likelihood is exacerbated by the Food and Drug Administration labeling rules, which allow products containing <0.5 g trans fat per serving to claim 0 g trans fat. Many products with almost 0.5 g trans fat, if consumed over the course of a day, may approximate or exceed the 2 g maximum as recommended by American Heart Association, all while claiming to be trans-fat free. Accordingly, greater transparency in labeling and/or active consumer education is needed to reduce the cardiovascular risks associated with trans fats.