Individual differences and moderating participant characteristics in the effect of reducing portion size on meal energy intake: Pooled analysis of three randomized controlled trials.
Ontology highlight
ABSTRACT:
SUBMITTER: Robinson E
PROVIDER: S-EPMC7816161 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:BACKGROUND:Smaller portions may help to reduce energy intake. However, there may be a limit to the magnitude of the portion size reduction that can be made before consumers respond by increasing intake of other food immediately or at later meals. We tested the theoretical prediction that reductions to portion size would result in a significant reduction to daily energy intake when the resulting portion was visually perceived as 'normal' in size, but that a reduction resulting in a 'smaller than normal' portion size would cause immediate or later additional eating. METHODS:Over three 5-day periods, daily energy intake was measured in a controlled laboratory study using a randomized crossover design (N?=?30). The served portion size of the main meal component of lunch and dinner was manipulated in three conditions: 'large-normal' (747?kcal), 'small-normal' (543?kcal), and 'smaller than normal' (339?kcal). Perceived 'normality' of portion sizes was determined by two pilot studies. Ad libitum daily energy intake from all meals and snacks was measured. RESULTS:Daily energy intake in the 'large-normal' condition was 2543 kcals. Daily energy intake was significantly lower in the 'small-normal' portion size condition (mean difference?-?95?kcal/d, 95% CI [-?184, -?6], p?= .04); and was also significantly lower in the 'smaller than normal' than the 'small-normal' condition (mean difference?-?210?kcal/d, 95% CI [-?309, -?111], p?<?.001). Contrary to predictions, there was no evidence that the degree of additional food consumption observed was greater when portions were reduced past the point of appearing normal in size. CONCLUSIONS:Reductions to the portion size of main-meal foods resulted in significant decreases in daily energy intake. Additional food consumption did not offset this effect, even when portions were reduced to the point that they were no longer perceived as being normal in size. TRIAL REGISTRATION:Prospectively registered protocol and analysis plan: https://osf.io/natws/; retrospectively registered: https://clinicaltrials.gov/ct2/show/NCT03811210.
| S-EPMC7017560 | biostudies-literature
Project description:BackgroundMeals differ in their nutritional content. This variation has not been fully addressed despite its potential contribution in understanding eating behavior. The aim of this study was to investigate the between-meal and between-individual variance in energy and macronutrient intake as a measure of variation in intake and the meal type-specific relative importance of predictors of these intake variations.MethodsEnergy and macronutrient intake were derived from three 24 h dietary recalls in an EPIC-Potsdam sub-cohort of 814 German adults. Intra-class correlation was calculated for participants and meal type. Predictors of intake were assessed using meal type-specific multilevel regression models in a structural equation modeling framework at intake and participant levels using the Pratt Index. The importance of the predictor energy misreporting was assessed in sensitivity analyses on 682 participants. 95% confidence intervals were calculated based on 1000 bootstrap samples.ResultsDifferences between meal types explain a large proportion of the variation in intake (intra-class correlation: 39% for energy, 25% for carbohydrates, 47% for protein, and 33% for fat). Between-participant variation in intake was much lower, with a maximum of 3% for carbohydrate and fat. Place of meal was the most important intake-level predictor of energy and macronutrient intake (Pratt Index of up to 65%). Week/weekend day was important in the breakfast meal, and prior interval (hours passed since last meal) was important for the afternoon snack and dinner. On the participant level, sex was the most important predictor, with Pratt Index of up to 95 and 59% in the main and in the sensitivity analysis, respectively. Energy misreporting was especially important at the afternoon snack, accounting for up to 69% of the explained variance.ConclusionsThe meal type explains the highest variation in energy and macronutrient intakes. We identified key predictors of variation in the intake and in the participant levels. These findings suggest that successful dietary modification efforts should focus on improving specific meals.
| S-EPMC6407220 | biostudies-literature
Project description:BackgroundCompeting theories attempt to explain changes in total energy (TE) intake; however, a rigorous, comprehensive examination of these explanations has not been undertaken. Our objective was to examine the relative contribution of energy density (ED), portion size (PS), and the number of eating/drinking occasions (EOs) to changes in daily TE.Methods and findingsUsing cross-sectional nationally representative data from the Nationwide Food Consumption Survey (1977-78), Continuing Survey of Food Intakes of Individuals (1989-91), and National Health and Nutrition Examination Surveys (1994-98 and 2003-06) for adults (aged ?19 y), we mathematically decompose TE (kcal/d) to understand the relative contributions of each component-PS (grams/EO), ED (kcal/g/EO) and EO(number)-to changes in TE over time. There was an increase in TE intake (+570 kcal/d) and the number of daily EOs (+1.1) between 1977-78 and 2003-06. The average PS increased between 1977-78 and 1994-98, then dropped slightly between 1994-98 and 2003-06, while the average ED remained steady between 1977-78 and 1989-91, then declined slightly between 1989-91 and 1994-98. Estimates from the decomposition statistical models suggest that between 1977-78 and 1989-91, annualized changes in PS contributed nearly 15 kcal/d/y to increases in TE, while changes in EO accounted for just 4 kcal/d/y. Between 1994-98 and 2003-06 changes in EO accounted for 39 kcal/d/y of increase and changes in PS accounted for 1 kcal/d/y of decline in the annualized change in TE.ConclusionsWhile all three components have contributed to some extent to 30-y changes in TE, changes in EO and PS have accounted for most of the change. These findings suggest a new focus for efforts to reduce energy imbalances in US adults.
| S-EPMC3125292 | biostudies-literature
Project description:Aging is often associated with overweight and obesity. There exists a long-standing debate about whether meal pattern also contributes to the development of obesity. The orexigenic hormone ghrelin regulates appetite and satiety by activating its receptor, growth hormone secretagogue receptor (GHS-R). In mice, circulating ghrelin concentrations and brain GHS-R expression were shown to increase with aging. To assess whether GHS-R regulates feeding pattern during aging, we studied meal patterns for the following cohorts of male mice fed a normal unpurified diet: 1) 3-4 mo, young wild-type (WT) mice; 2) 3-4 mo, young Ghsr-null (Ghsr(-/-)) mice; 3) 12-14 mo, middle-aged WT (WT-M) mice; 4) 12-14 mo, middle-aged Ghsr(-/-) (Ghsr(-/-)-M) mice; 5) 24-26 mo, old WT (WT-O) mice; and 6) 24-26 mo, old Ghsr(-/-) (Ghsr(-/-)-O) mice. Although the total daily food intake of Ghsr(-/-) mice was similar to that of WT controls, Ghsr(-/-)-M and Ghsr(-/-)-O mice had 9% (P = 0.07) and 16% (P < 0.05) less body weight compared with WT-M and WT-O mice, respectively, primarily due to reduced fat mass (P < 0.05, WT-M vs. Ghsr(-/-)-M and WT-O vs. Ghsr(-/-)-O). Intriguingly, Ghsr(-/-)-M mice ate larger meals (on average, Ghsr(-/-)-M mice ate 0.117 g/meal and WT-M mice ate 0.080 g/meal; P < 0.01) and took a longer time to eat (Ghsr(-/-)-M, 196.0 s and WT-M, 128.9 s; P < 0.01), but ate less frequently (Ghsr(-/-)-M, 31.0 times/d and WT-M, 42.3 times/d; P < 0.05) than WT-M controls. In addition, we found that expression of hypothalamic orexigenic peptides, neuropeptide Y (NPY) and agouti-related peptide (AgRP), was relatively lower in aged WT mice (P = 0.09 for NPY and P = 0.06 for AgRP), but anorexic peptide pro-opiomelanocortin (POMC) expression remained unchanged between the WT age groups. Interestingly, old Ghsr(-/-) mice had greater hypothalamic NPY expression (102% higher; P < 0.05) and AgRP expression (P = 0.07) but significantly lower POMC expression (P < 0.05) when compared with age-matched WT-O controls. Thus, our results indicate that GHS-R plays an important role in the regulation of meal pattern and that GHS-R ablation may modulate feeding behavior through the regulation of hypothalamic neuropeptides. Our results collectively suggest that ghrelin receptor antagonism may have a beneficial effect on metabolism during aging.
| S-EPMC4130825 | biostudies-other
Project description:People typically eat more from large portions of food than from small portions. An explanation that has often been given for this so-called portion size effect is that the portion size acts as a social norm and as such communicates how much is appropriate to eat. In this paper, we tested this explanation by examining whether manipulating the relevance of the portion size as a social norm changes the portion size effect, as assessed by prospective consumption decisions. We conducted one pilot experiment and one full experiment in which participants respectively indicated how much they would eat or serve themselves from a given amount of different foods. In the pilot (N = 63), we manipulated normative relevance by allegedly basing the portion size on the behavior of either students of the own university (in-group) or of another university (out-group). In the main experiment (N = 321), we told participants that either a minority or majority of people similar to them approved of the portion size. Results show that in both experiments, participants expected to serve themselves and to eat more from larger than from smaller portions. As expected, however, the portion size effect was less pronounced when the reference portions were allegedly based on the behavior of an out-group (pilot) or approved only by a minority (main experiment). These findings suggest that the portion size indeed provides normative information, because participants were less influenced by it if it communicated the behaviors or values of a less relevant social group. In addition, in the main experiment, the relation between portion size and the expected amount served was partially mediated by the amount that was considered appropriate, suggesting that concerns about eating an appropriate amount indeed play a role in the portion size effect. However, since the portion size effect was weakened but not eliminated by the normative relevance manipulations and since mediation was only partial, other mechanisms may also play a role.
| S-EPMC4885850 | biostudies-literature
Project description:Large portions promote intake of energy dense foods (i.e., the portion size effect--PSE), but the neurobiological drivers of this effect are not known. We tested the association between blood oxygen level dependent (BOLD) brain response to food images varied by portion size (PS) and energy density (ED) and children's intake at test-meals of high- and low-ED foods served at varying portions. Children (N?=?47; age 7-10 years) participated in a within-subjects, crossover study consisting of 4 meals of increasing PS of high- and low-ED foods and 1 fMRI to evaluate food images at 2 levels of PS (Large, Small) and 2 levels of ED (High, Low). Contrast values between PS conditions (e.g., Large PS - Small PS) were calculated from BOLD signal in brain regions implicated in cognitive control and reward and input as covariates in mixed models to determine if they moderated the PSE curve. Results showed a significant effect of PS on intake. Responses to Large relative to Small PS in brain regions implicated in salience (e.g., ventromedial prefrontal cortex and orbitofrontal cortex) were positively associated with the linear slope (i.e., increase in intake from baseline) of the PSE curve, but negatively associated with the quadratic coefficient for the total meal. Responses to Large PS High ED relative to Small PS High ED cues in regions associated with cognitive control (e.g., dorsolateral prefrontal cortex) were negatively associated with the linear slope of the PSE curve for high-ED foods. Brain responses to PS cues were associated with individual differences in children's susceptibility to overeating from large portions. Responses in food salience regions positively associated with PSE susceptibility while activation in control regions negatively associated with PSE susceptibility.
| S-EPMC5878726 | biostudies-literature
Project description:Portion control utensils and reduced size tableware amongst other tools, have the potential to guide portion size intake but their effectiveness remains controversial. This review evaluated the breadth and effectiveness of existing portion control tools on learning/awareness of appropriate portion sizes (PS), PS choice, and PS consumption. Additional outcomes were energy intake and weight loss. Published records between 2006-2020 (n = 1241) were identified from PubMed and WoS, and 36 publications comparing the impact of portion control tools on awareness (n = 7 studies), selection/choice (n = 14), intake plus related measures (n = 21) and weight status (n = 9) were analyzed. Non-tableware tools included cooking utensils, educational aids and computerized applications. Tableware included mostly reduced-size and portion control/calibrated crockery/cutlery. Overall, 55% of studies reported a significant impact of using a tool (typically smaller bowl, fork or glass; or calibrated plate). A meta-analysis of 28 articles confirmed an overall effect of tool on food intake (d = -0.22; 95%CI: -0.38, -0.06; 21 comparisons), mostly driven by combinations of reduced-size bowls and spoons decreasing serving sizes (d = -0.48; 95%CI: -0.72, -0.24; 8 comparisons) and consumed amounts/energy (d = -0.22; 95%CI: -0.39, -0.05, 9 comparisons), but not by reduced-size plates (d = -0.03; 95%CI: -0.12, 0.06, 7 comparisons). Portion control tools marginally induced weight loss (d = -0.20; 95%CI: -0.37, -0.03; 9 comparisons), especially driven by calibrated tableware. No impact was detected on PS awareness; however, few studies quantified this outcome. Specific portion control tools may be helpful as potentially effective instruments for inclusion as part of weight loss interventions. Reduced size plates per se may not be as effective as previously suggested.
| S-EPMC8229078 | biostudies-literature
Project description:It is widely assumed that people with obesity have several common eating patterns, including breakfast skipping, eating during the night and high fast-food consumption. However, differences in individual meal and dietary patterns may be crucial to optimising obesity treatment. Therefore, we investigated the inter-individual variation in eating patterns, hypothesising that individuals with obesity show different dietary and meal patterns, and that these associate with self-reported energy intake (rEI) and/or anthropometric measures. Cross-sectional data from 192 participants (aged 20-55 years) with obesity, including 6 d of weighed food records, were analysed. Meal patterns and dietary patterns were derived using exploratory hierarchical cluster analysis and k-means cluster analysis, respectively. Five clear meal patterns were found based on the time-of-day with the highest mean rEI. The daily rEI was highest among 'midnight-eaters' (10 669 (sd 2301) kJ), and significantly (P < 0·05) higher than 'dinner-eaters' (8619 (sd 2301) kJ), 'lunch-eaters' (8703 (sd 2176) kJ) and 'supper-eaters' (8786 (sd 1925) kJ), but not 'regular-eaters' (9749 (sd 2720) kJ). Despite differences of up to 2050 kJ between meal patterns, there were no significant differences in anthropometric measures or physical activity level (PAL). Four dietary patterns were also found with significant differences in intake of specific food groups, but without significant differences in anthropometry, PAL or rEI. Our data highlight meal timing as a determinant of individual energy intake in people with obesity. The study supports the importance of considering a person's specific meal pattern, with possible implications for more person-focused guidelines and targeted advice.
| S-EPMC9301523 | biostudies-literature
Project description:Context:Anemia and thyroid dysfunction often co-occur, and both increase with age. Human data on relationships between thyroid disease and anemia are scarce. Objective:To investigate the cross-sectional and longitudinal associations between clinical thyroid status and anemia. Design:Individual participant data meta-analysis. Setting:Sixteen cohorts participating in the Thyroid Studies Collaboration (n = 42,162). Main Outcome Measures:Primary outcome measure was anemia (hemoglobin <130 g/L in men and <120 g/L in women). Results:Cross-sectionally, participants with abnormal thyroid status had an increased risk of having anemia compared with euthyroid participants [overt hypothyroidism, pooled OR 1.84 (95% CI 1.35 to 2.50), subclinical hypothyroidism 1.21 (1.02 to 1.43), subclinical hyperthyroidism 1.27 (1.03 to 1.57), and overt hyperthyroidism 1.69 (1.00 to 2.87)]. Hemoglobin levels were lower in all groups compared with participants with euthyroidism. In the longitudinal analyses (n = 25,466 from 14 cohorts), the pooled hazard ratio for the risk of development of anemia was 1.38 (95% CI 0.86 to 2.20) for overt hypothyroidism, 1.18 (1.00 to 1.38) for subclinical hypothyroidism, 1.15 (0.94 to 1.42) for subclinical hyperthyroidism, and 1.47 (0.91 to 2.38) for overt hyperthyroidism. Sensitivity analyses excluding thyroid medication or high levels of C-reactive protein yielded similar results. No differences in mean annual change in hemoglobin levels were observed between the thyroid hormone status groups. Conclusion:Higher odds of having anemia were observed in participants with both hypothyroid function and hyperthyroid function. In addition, reduced thyroid function at baseline showed a trend of increased risk of developing anemia during follow-up. It remains to be assessed in a randomized controlled trial whether treatment is effective in reducing anemia.
| S-EPMC6179176 | biostudies-literature
Project description:Laboratory studies have demonstrated that experimental manipulations of oral processing can have a marked effect on energy intake. Here, we explored whether variations in oral processing across a range of unmodified everyday meals could affect post-meal fullness and meal size. In Study 1, female participants (N = 12) attended the laboratory over 20 lunchtime sessions to consume a 400-kcal portion of a different commercially available pre-packaged meal. Prior to consumption, expected satiation was assessed. During each meal, oral processing was characterised using: (i) video-recordings of the mouth and (ii) real-time measures of plate weight. Hunger and fullness ratings were elicited pre- and post-consumption, and for a further three hours. Foods that were eaten slowly had higher expected satiation and delivered more satiation and satiety. Building on these findings, in Study 2 we selected two meals (identical energy density) from Study 1 that were equally liked but maximised differences in oral processing. On separate days, male and female participants (N = 24) consumed a 400-kcal portion of either the "fast" or "slow" meal followed by an ad libitum meal (either the same food or a dessert). When continuing with the same food, participants consumed less of the slow meal. Further, differences in food intake during the ad libitum meal were not compensated at a subsequent snacking opportunity an hour later. Together, these findings suggest that variations in oral processing across a range of unmodified everyday meals can affect fullness after consuming a fixed portion and can also impact meal size. Modifying food form to encourage increased oral processing (albeit to a lesser extent than in experimental manipulations) might represent a viable target for food manufacturers to help to nudge consumers to manage their weight.
| S-EPMC4882727 | biostudies-literature