Food waste concerns, eating behaviour and body weight

Downsizing food: a systematic review and meta-analysis examining the effect of reducing served food portion sizes on daily energy intake and body weight

Portion sizes of many foods have increased over time. However, the size of effect that reducing food portion sizes has on daily energy intake and body weight is less clear. We used a systematic review methodology to identify eligible articles that used an experimental design to manipulate portion size served to human participants and measured energy intake for a minimum of 1 d. Searches were conducted in September 2020 and again in October 2021. Fourteen eligible studies contributing eighty-five effects were included in the primary meta-analysis. There was a moderate-to-large reduction in daily energy intake when comparing smaller v. larger portions (Standardised Mean Difference (SMD) = -0·709 (95 % CI: -0·956, -0·461), approximately 235 kcal (983·24 kJ)). Larger reductions to portion size resulted in larger decreases in daily energy intake. There was evidence of a curvilinear relationship between portion size and daily energy intake; reductions to daily energy intake were markedly smaller when reducing portion size from very large portions. In a subset of studies that measured body weight (four studies contributing five comparisons), being served smaller v. larger portions was associated with less weight gain (0·58 kg). Reducing food portion sizes may be an effective population-level strategy to prevent weight gain.

On the measurement and correlates of plate clearing: examining a German version of the Plate Clearing Tendency Scale

PURPOSE

Plate clearing-eating a meal in its entirety-is common and may be a factor contributing to obesity. For the assessment of individual differences in plate clearing tendencies, Robinson et al. (Obesity 23:301-304, 2015) developed the Plate Clearing Tendency Scale (PCTS). However, little is known about the psychometric properties of this scale and its correlates.

METHODS

In the current study, participants (N = 207, 76% female) completed a German translation of the PCTS and other questionnaires online.

RESULTS

A one-factor structure had good model fit and the PCTS had acceptable internal reliability and good test-retest reliability across an average of four and a half weeks. Higher plate clearing tendencies related to more frequent parental encouragement to clear one's plate in childhood and to stronger food waste concerns but were unrelated to sex, body weight, self-control, and eating behaviors. However, higher plate clearing tendencies related to higher body weight in unsuccessful dieters.

CONCLUSION

The current study shows that the PCTS has sound psychometric properties and that plate clearing tendencies appear to be largely driven by food waste concerns and not by automatic eating habits or low eating-related self-control. In dieters, however, high plate clearing tendencies may contribute to low dieting success and hinder weight loss.

LEVEL OF EVIDENCE

No level of evidence, basic science.

The impact of increasing the availability of lower energy foods for home delivery and socio-economic position: a randomised control trial examining effects on meal energy intake and later energy intake

Increasing the availability of lower energy food options is a promising public health approach. However, it is unclear the extent to which availability interventions may result in consumers later 'compensating' for reductions in energy intake caused by selecting lower energy food options and to what extent these effects may differ based on socio-economic position (SEP). Our objective was to examine the impact of increasing availability of lower energy meal options on immediate meal energy intake and subsequent energy intake in participants of higher v. lower SEP. In a within-subjects design, seventy-seven UK adults ordered meals from a supermarket ready meal menu with standard (30 %) and increased (70 %) availability of lower energy options. The meals were delivered to be consumed at home, with meal intake measured using the Digital Photography of Foods Method. Post-meal compensation was measured using food diaries to determine self-reported energy intake after the meal and the next day. Participants consumed significantly less energy (196 kcal (820 kJ), 95 % CI 138, 252) from the menu with increased availability of lower energy options v. the standard availability menu (P < 0·001). There was no statistically significant evidence that this reduction in energy intake was substantially compensated for (33 % compensated, P = 0·57). The effects of increasing availability of lower energy food items were similar in participants from lower and higher SEP. Increasing the availability of lower energy food options is likely to be an effective and equitable approach to reducing energy intake which may contribute to improving diet and population health.

Sociocultural Influences Contribute to Overeating and Unhealthy Eating: Creating and Maintaining an Obesogenic Social Environment in Indigenous Communities in Urban Fiji

Pacific Island countries (PICs), such as Fiji, lead the world statistics in obesity and deaths caused by non-communicable diseases. The impacts of obesity overburden the healthcare system and social services and have major impacts on the Fijian economy. This study is the first of its kind to undertake an in-depth exploration of the determinants of the obesity epidemic in PICs by exploring the sociocultural influences and situations that impact nutrient transitions, overconsumption, and unhealthy eating in an urban indigenous community. In-depth qualitative interviews were conducted with 15 indigenous Fijian women from the largest urban center in Fiji who self-identified as gatekeepers of family meal planning, preparing, and shopping for groceries, fruits, and vegetables. The women identified several cultural norms and expectations of both the individuals providing the food and the individuals consuming the food that create and maintain an obesogenic social environment. Moreover, participants also shared a misplaced value on meat, energy-dense foods, junk food, and fast foods that further contribute to unhealthy eating and overeating within this urban indigenous community. These novel findings highlight the importance of considering sociocultural influences on unhealthy eating and overeating and may be used to assist decision-makers in developing contextualized obesity prevention strategies and health messaging to target obesity in this community.

The relationship between traditional and common Japanese childhood education and adulthood towards avoiding food waste behaviors

Japanese parents and educators teach children to refrain from leaving food in their plates. Their teachings have direct (advising children to refrain from leaving food uneaten) and indirect (meal-related rituals before and after mealtimes) influence in enhancing gratitude for food in daily life. This cross-sectional study aimed to examine 1) the interaction of direct and indirect approaches to avoiding food waste behaviors and 2) the mediation of gratitude for food by preventing such behaviors. Overall, 400 Japanese adults (female: n = 200) responded to a self-administrated anonymous questionnaire survey measuring: the present food waste avoiding behaviors; current gratitude for food; direct and indirect childhood approaches for avoiding food waste behaviors. Participants' mean (standard deviation) age and body mass index were 40.0 (11.6) and 21.9 (3.9), respectively. A significant main effect of the indirect approach and the interaction of direct and indirect approaches were obtained by adjusting the participants' background. Moreover, through mediation analyses with percentile-corrected bootstrap confidence intervals, it was observed that gratitude for food mediated the association between direct and indirect childhood approaches and avoiding food waste behaviors. Despite no information on the current meal-related rituals of the respondents, this study suggests the potential of these approaches in enhancing gratitude for food as a new approach to reduce food waste worldwide.

Are the Slimmer More Wasteful? The Correlation between Body Mass Index and Food Wastage among Chinese Youth

With the economic growth and living standard improvement, food waste has become increasingly common among Chinese youth. To test whether body size affects the food waste performance of youth, we examined university students as representative of the Chinese youth and conducted a large-sample survey in 29 universities across 29 provinces. Based on 9192 questionnaires collected from Chinese college canteens, we found that body size was correlated with food waste. The smaller the body mass index (BMI) value, the higher the likelihood of plate waste, the higher the amount of waste, and the higher the ratio of food waste. Heterogeneity analyses revealed that BMI exerted a more significant impact on males than females, as well as a more substantial impact on northerners than southerners. Robust tests using other proxies to measure body size, robust regressions based on the new adjusted samples, and robust tests with an instrumental variable to overcome the endogenous issue suggested that the slimmer participants tended to be more wasteful. Hence, this study confirms that the slimmer youth tend to leave plate waste and waste more food per capita per meal. This study is the first attempt to analyze food wastage from the perspective of BMI in China to our best knowledge, and it provides a unique viewpoint for understanding young people’s food wastage.

"Stay at Home": The Effects of the COVID-19 Lockdown on Household Food Waste in Colombia

Household food waste represents one of the main challenges for sustainable development as this directly affects the economy of food consumers, the loss of natural resources and generates additional greenhouse gas emissions. The COVID-19 pandemic and its mitigation strategies caused one of the most serious economic crises in recent decades and could become the worst economic crisis that Latin America has had in its history. The objective of this study is to analyze changes in food waste behavior during the COVID-19 lockdown in Colombia in 2020, applying the Theory of Planned Behavior (TPB). For this purpose, we conducted a survey with 581 Colombian food consumers, which examined the influence of intentions to not waste food, subjective norms, some situational predictors, questions related to the COVID-19 pandemic, and the control of perceived behavior on food waste. The results suggest that the TPB can predict the intention to not waste food and, through it, the actual household food waste behavior, considering the lockdown in Colombia as an external shock. We observe that regarding the intention to not waste food, the most relevant variables are attitudes, subjective norms, control of the perceived behavior, and concerns regarding the Covid-19 pandemic. These variables increase the probability on average by a 0.8 Odds Ratio that the intention not to waste food increases, too. Regarding food waste behavior, whether it is considered ordinal or nominal, we see that the most relevant variables are intention, financial attitudes, and control of perceived behavior, doubling the probability that food waste behavior will improve. Based on the results, we provide recommendations for interested stakeholders that can help in the design of instruments for household food waste reduction.

"Waste not and stay at home" evidence of decreased food waste during the COVID-19 pandemic from the U.S. and Italy

The COVID-19 pandemic has profoundly disrupted household food purchasing and preparation, including elements identified as important drivers of household food waste. The two main aims of this study were (1) to examine changes in food waste behaviors since the start of the COVID-19 pandemic in the U.S. and Italy; and (2) to investigate potential predictors of food waste behavior, including avoidance of supermarkets, increased home cooking, and increased role of health concerns in food choices. A sample of n = 478 (79% female) individuals from the U.S., mean (SD) age = 30.51 (10.85), and n = 476 individuals from Italy, (78% female), mean (SD) age = 33.84 (12.86), completed an online survey between April 8th and April 28^th 2020. Just under half of respondents (49%) reported decreased food waste since the start of the pandemic. Rates were significantly higher among the U.S. sample (61.5%, n = 294) compared to the Italian sample (38%, n = 180). Controlling for the time since restrictions were introduced, age, gender, and perceived financial security, logistic regression revealed greater reduction in food waste since the beginning of the pandemic for U.S. individuals relative to participants from Italy (OR = 0.47, p < .001). In addition, increased importance of health concerns when making food choices (OR = 1.34, p < .005) as well as more frequent cooking (OR = 1.35, p < .001), and greater avoidance of supermarkets (OR = 1.15, p = .049) were associated with greater probability of less food waste. Scarcity and greater reliance on cooking may encourage individuals to reflect on food waste practices. Further research should explore how these factors may be targeted to reduce food waste beyond the pandemic.