The Effect Of Physical Activity Calorie Equivalent(PACE) Labeling On High-and Low-calorie Food Choices

Currently,our environment is full of temptations of various food cues and high-calorie foods are readily available.This obesogenic environment is the cause of the imbalance between individual energy intake and consumption.Food labeling is receiving increasing attention from researchers as a key health policy strategy to address rising obesity rates and reduce costs associated with the healthcare system.Among these,the physical activity calorie equivalence(PACE)label,as a label that combines the reductive and explanatory features of front-of-package(FOP)food labels,can provide some sort of benchmark or reference value for individuals to facilitate better judgment of the overall health status of a product and to make healthy choices.First,while many Western countries have conducted more in-depth studies on nutrition labeling processing,little research has been conducted on the processing and effects of nutrition labels in developing countries;second,there is no consensus on the research findings regarding the effects of calorie labeling and PACE labeling on individual food assessment and selection,and the utility of calorie labeling and PACE labeling still needs to be further examined and discussed;finally,the existing research on PACE labeling is still mainly at the behavioral level,and no research has been conducted to investigate the effect of this label on food choice from the neurophysiological perspective of psychogenesis,which will help to solve the question of why PACE labeling works and is important for the practical promotion of the label.Based on the above research background,this study focuses on the following three questions:(1)whether PACE labels can influence individuals’ reward value evaluation and choice intention assessment of high-and low-calorie foods(Study 1);(2)Whether PACE labels can influence individuals’ choice of high-and low-calorie foods presented in pairs and visual attention,and whether there are differences in the duration of fixation and number of fixations with respect to the food and the corresponding label;(Study 2);(3)How individuals’ brains are active during the selection of high-and low-calorie foods with PACE labels relative to calorie labels,and what are the specific neurophysiological performances(Study 3).This study included three sub-studies.One of them,Study 1(N=53)explored the effects of different labels on reward value(deliciousness,liking,emotional arousal)evaluation of high-and lowcalorie foods and choice(likelihood to choose)by using a 4(label type: no label,calorie label,PACE(distance)label,PACE(step count)label)*2(food type: high-calorie,low-calorie)within-subject design.A repeated measures ANOVA found that the PACE(distance)label was effective in reducing individuals’ reward value evaluations of high-calorie foods and that both PACE labels reduced willingness to choose high-calorie foods,validating the effectiveness of previous PACE labels in influencing food perceptions and willingness to choose.Study 2(N=46)used an eye-movement technique to objectively measure and record the duration and number of gaze movements of individuals during the selection of high-and low-calorie foods with different labels.Behavioral results found that PACE labels significantly reduced individuals’ selection of high-calorie foods compared to no label and calorie label;eye-movement data analysis revealed that,overall,individuals spent more time fixing on label areas of interest(AOIs)than at food AOIs when calorie-related labels were present compared to no label.Furthermore,under the PACE(distance)condition,there was a decreasing trend of the difference in the duration time of fixation between the AOIs of high-and low-calorie foods and the time on the label AOI of low-calorie foods was significantly higher than the label AOI of high-calorie foods.It was also found that compared to no label and calorie label,when the PACE label was presented,there were significantly more fixation counts on the label AOIs corresponding to high-and low-calorie foods than to the food AOIs corresponding to high-and low-calorie foods,in addition to significantly more fixation counts on the label AOI corresponding to low-calorie foods than on the label AOI corresponding to high-calorie foods.Study 3(N=28)used the ERP technique to measure and record the electrophysiological brain activity of individuals under calorie label and PACE label when making high-and low-calorie food choices.Behavioral results found that the two labels did not differ significantly in food choice rates;analysis of the EEG data revealed that individuals facing high-calorie foods with PACE label allocated more attention and cognitive resources and induced larger N1 wave amplitudes;automatically elicited more positive emotions and induced smaller P2 wave amplitudes compared to calorie label.The main innovation of this study is the integration of three aspects: behavioural,visual attention and neurophysiological mechanisms of the brain to explore the influence of food calorie labelling,especially PACE labelling,on food choice.The main innovations are as follows:(1)The sample group was extended to verify the validity of the PACE label in a sample of Chinese university students,further expanding the psychological research in the field of food labelling.(2)This study replicates and tests the impact of PACE label by using a larger number and different categories(high-and low-calorie)of foods in the intended consumption setting,broadening the parameters of currently known PACE messages,excluding product-specific effects,and further arguing for the broad applicability of PACE labelling.(3)This study uses the ERP paradigm to explore the psychological mechanisms underlying the role of calorie labelling on food choice,breaking the limitations of the previous reliance on subjects’ subjective self-reports,and to a certain extent leading the study of calorie labelling to the neurophysiological level,providing certain directions for future research.In summary,this study validates and advances the effectiveness of the PACE label as an effective strategy to intervene in the rising obesity rate,which provides data support and theoretical support for policy formulation.