Ji Lu , Aida Faber , and Laurette Dubé
Key Points
• To better understand the superior nutritional quality of home meals vs.
away-from-home meals, two protective mechanisms are proposed and empirically explored: emotional reinforcement and attachment style.
• Beyond the biological reinforcement process, in which eating is natu- rally rewarded by sensory and hedonic experiences, emotions can be associated with eating, adding emotional reinforcing properties to food consumption.
• Home may be a place of foremost importance for emotional reinforce- ment in that, compared to away-from-home settings, more positive emotions are experienced and can be attached to food consumed in this setting. As such, emotional reinforcement processes particularly bene- fi t healthy foods, because they are generally lacking biological rein- forcing properties.
• It is highly plausible that emotional reinforcement as a protective mechanism of home eating starts from early stage of life through the parent/child attachment relationship where both primary caregivers and food are the two most central objects in a child’s life.
• By providing a secure environment to explore and learn—mainly the home environment—nurturing and caring parents establish a secure attachment with their children. Such secure attachment styles promote emotional reinforcement and become internalized, forming the base for life-long healthy eating patterns.
Introduction
It is widely observed that food consumption, in terms of its nutritional quality, is typically healthier at home than in away-from-home settings [ 1 , 2 ];
supporting evidences were extensively documented in the chapter by Woodruff and Hanning showing an important association between family meals and diet quality. This leads to the present chap- ter’s theoretical interest of taking an evidence- based approach to further explore the underlying mechanisms contributing to the protective effects of home on healthy eating. Using theoretical rationales and empirical examinations, this chap- ter proposes that emotional reinforcement and parent/child attachment style are potential protec- tive mechanisms accounting for healthier eating patterns occurring at home. Particularly, we will fi rst examine evidence revealing that positive moods experienced at home can be associated with food consumption, especially with healthy food intake, therefore increasing the emotional reinforcing value of healthy meals at home. We will then demonstrate that a trusting and caring parent/child relationship starting as early as birth and internalized as a secure attachment style may facilitate such an emotional reinforcement and lead to a life-long healthier eating habits.
Closely tied to the pleasure brought by the taste of food, eating is generally rewarded by biological signals sent by the sensory and hedonic systems. This biological reinforcing property of food is particularly salient for
unhealthy foods (high in sugar and/or fat) because of their superior palatability compared to healthy foods (low in sugar and/or fat) [ 3 ].
Beyond biological pleasure, emotional experi- ences can also be associated with eating through an emotional reinforcement process [ 4 ]. It has been shown that the home as opposed to the out- side environment (work places, schools, etc.) is a more intense source of positive emotional experiences [ 5 ]. Through an associative learn- ing process, the positive affective states experi- enced at home can become attached to food consumed in this setting, assigning home meals a superior emotional reinforcing value.
Moreover, because healthy food lacks a strong biological reinforcing property, emotional rein- forcement tends to manifest its protective effect particularly on this type of food which is low in sugar and/or fat. Interestingly, these associa- tions between positive emotions and food start as early as birth; mostly within home settings, where sensitive and caring parents provide important opportunities to infants to experience with food and eating in a calm and safe environ- ment [ 6 ]. Over time, these experiences are inter- nalized and constitute the cornerstone for individuals to interpret emotions and assign emotional value to eating experiences [ 6 ].
Therefore, the home becomes a haven where positive emotions are more likely to arise and, through powerful and early conditioning, to become associated with healthier food consump- tion which lacks the high biological reinforce- ment of unhealthy food alternatives.
• This mechanism was empirically explored in a survey about attachment style and high fat/high sugar food consumption. For children and adults, more trusting bonds (lower avoidance) and lower anxiety and worry about their relationship with their own parents (lower anxiety) were linked with lower consumption of unhealthy foods.
• Potential interventions and future studies are discussed.
Keywords
Eating behavior • Food choices • Reinforcement • Emotions • Home meals
• Attachment style • Avoidant attachments • Anxious attachment • Food consumption
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Identifying processes through which eating at home becomes associated with healthy eating habits is essential, not only because home meals still represent the bulk of food consumption worldwide, but also because food habits are formed in the fi rst 5 years of life (mostly at home) and serve as a foundation for eating throughout the life course [ 7 ]. Understanding these mechanisms will allow for the development of interventions that may impact eating and healthy lifestyles, and that can be implemented as early as birth.
Emotional Reinforcement as a Protective Mechanism of Home
Reinforcement and Food Consumption
Reinforcement is a process of associating a behav- ior with contingent positive consequences or the alleviation of negative states as rewards [ 8 ]. Food is a powerful primary reinforcer in that (1) eating is repeatedly paired with biological positive out- comes, such as pleasant taste and the decrease of hunger feelings; and (2) the learned association between food and such positive occurrences moti- vates further behaviors to obtain it, therefore, food consumption can be triggered by physiological signals of hunger and/or olfactory and visual food cues that suggest opportunities to get reward.
Furthermore, foods vary in their biological reinforcing qualities, with highly reinforcing foods being favored over less reinforcing ones [ 9 ]. The biological reinforcing quality of a specifi c food is closely related to the sensory and hedonic signals triggered by the subjective pleasure of taste which conceptually incorporates palatability, smell, and food texture. It has been shown that individuals inherently prefer unhealthy foods, which are high in sugar and/or fat (e.g., French fries, pizza, or ice cream), fi nding these foods tastier and therefore more biologically reinforcing [ 10 , 11 ], compared to healthy foods (e.g., whole grains, low fat yogurt, or vegetables). Moreover, individuals are biologi- cally programmed to avoid bitter taste as it is associated with poison. This makes some vegeta- bles such as Brussels sprouts and broccolis not
only less preferred because of their lack of biologi- cal reinforcement qualities but sometimes outright rejected regardless of their benefi cial nutritional qualities [ 12 ].
Emotions are often at the core of the reinforce- ment process infl uencing motivated behavior [ 8 ].
For eating, immediate taste evaluation along the dimension of positive–negative food acceptabil- ity activates the entire affective system, triggering not only simple hedonic experiences (like/dislike) but also more differentiated affective states such as enjoyment, accomplishment, sadness, anxiety, melancholy, or guilt [ 13 ]. Furthermore, food consumption is a complex behavior; beside the biological signals related to the appreciation of palatability, eating can be reinforced by emotional experiences and motivated by emotional regula- tion needs. As shown in our published studies, the consumption of comfort food can result in increased positive emotions or provide allevia- tion from negative moods [ 14 ]. Such associations between food and emotional comfort, carved in the mind as a schema, assigns emotional rein- forcing properties to food consumption [ 15 ]. We further showed in these studies that individual emotional experiences associated with comfort food are critically moderated by social-cultural factors, such as gender and cultural background.
This evidence points to the importance of post- natal environment (e.g., the context that individ- uals consistently experience both food and certain emotions) in the emotional reinforcement process.
Home Environment and the Emotional Reinforcement of Food Focusing on positive emotions, we propose that emotions arising from the consumption context can be associated with the food consumed, and can be integrated into the reinforcing value as a contingent consequence rewarding consumption or as an antecedent state triggering eating. It has been shown that enjoyable social interactions and pleasant environments [ 16 ], if stably paired with eating, may become associated with food con- sumption, altering its reinforcing properties and
3 An Evidence-Based Approach to the Nutritional Quality of Home Meals…
ultimately infl uencing food choices [ 13 ]. As a unique set of social-cultural and physical-environ- mental factors, the home can greatly infl uence the reinforcing quality of food through an associative learning process. Individuals typically experience more intense positive emotions and less intense negative emotions at home than in work places and other away-from-home contexts [ 5 , 17 ] and tend to associate such ambient affects with the ongoing activities they perform in this environ- ment [ 18 ]. Through repeated interactions with food at home in the presence of positive emotions, people may come to associate these positive affec- tive states with food consumed at home and attach an emotional reinforcing value to home meals.
We further suggest that one of the protective mechanisms of the home environment is that the higher emotionally reinforcing value attached to food eaten at home should be particularly salient for healthy meals rather than unhealthy ones.
As previously mentioned in this chapter, unhealthy food is biologically rewarded primarily by its desirable taste. Because of the powerful infl uence of biological signals [ 19 ], when con- suming high fat/sugar foods, individuals tend to focus their attention to the hedonic experiences brought by the food and are less likely process contextual information, including emotional sig- nals, from their surrounding environment [ 20 ].
Therefore, positive emotional states tied to the home are less likely to be actually experienced and hence are hard to attach to foods rich in sugar and fat. On the other hand, healthy meals lack an inherent biological reinforcing value effectively leaving space for the emotional reinforcing qual- ity to be attached to them. Hence, without the attention- narrowing effect derived from biologi- cal reward, the superior emotional states of home, compared to away-from-home settings, can be more saliently experienced when consuming healthy food. If stably paired with each other, the superior value of positive contextual emotions becomes associated with healthy meals consumed in the same environment, adding an emotional reinforcing value to healthy food.
As a result of such an associative learning pro- cess, which involves a set of emotions, healthy foods, and the home as a physical-psychological
context, pre-consumption positive emotions that align with the rewarding property of healthy foods may serve as triggering cues to motivate behavior to pursue healthy eating, especially at home. This proposition is consistent with studies exploring the effects of positive emotions, as antecedent states, on food intake. For example, it has been shown that positive emotions, such as happiness, calm, and joy, can increase an indi- vidual’s motivation to eat [ 21 ] particularly trig- gering healthy food consumption and healthful food preferences [ 14 ].
To empirically explore the proposed protective mechanism of home on healthy eating, we will shortly review our published empirical study [ 22 ] to illustrate how meal location (home vs. away- from-home) and emotions (positive vs. negative) interact to infl uence food choice (healthy vs.
unhealthy) and discuss some methodological issues related to home meal research.
An Empirical Examination of Food, Emotions, and Location
Baseline Meal Food Choice Pattern The primary goal of this study was to test the hypothesis that home is a central setting, where eating, especially healthy eating, is emotionally reinforced. In the midst of everyday life, contex- tual factors affect individual choice and behavior in each occasion; while across occasions (e.g., breakfast, lunch, and dinner), stable patterns of behavior can be identifi ed and individual differ- ences regarding such stable patterns can be mani- fested [ 23 ]. It has been consistently shown that food choices vary systematically across daily meals, with low-caloric foods most likely being chosen at breakfast, while the tasty, caloric- intense food more likely being chosen at dinner [ 24 ]. Such habitual eating patterns were referred as baseline habits, and individuals were found generally to exhibit these baseline habits in their food choices [ 23 ]. Such baseline habits are mainly shaped by social-cultural forces [ 25 ] and are relatively independent of emotional reinforc- ing value. Therefore, an empirical comparison of
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emotional reinforcing value across meals with healthy or unhealthy content should be based on each meal’s relative deviation from an individual’s baseline habit rather than on absolute nutritional quality of a meal.
Emotional Reinforcing Property of Meals
Our empirical study operationalizes emotional reinforcing value as an association between posi- tive mood and food consumption. First, having a home meal, if it is more emotional reinforcing than other meals, should result in a better mood as a positive emotional consequence. Therefore, a better post-meal affective state is one of the indica- tors suggesting a higher emotional reinforcing value being attached to home meals. Second, within the home setting, if healthier meals are more emotional reinforcing than unhealthy meals, then the healthier meals are expected to trigger more intensive positive and/or less negative post- meal affective states. Third, as an antecedent state, positive mood can serve as a conditioned cue to motivate a reward seeking behavior.
Hence, another way to operationalize emotional reinforcing value is to examine the premeal affec- tive states as a trigger of food choice. As a context of associative learning, the home setting activates or enhances the associative link between healthy
meals and positive affective states, while the effect of such emotional reinforcement may not be as powerful in away-from-home settings. Hence, healthier meals, especially those consumed at home, should be preceded by more positive pre- meal emotion and/or less negative emotions.
Research Paradigm and Results
We used experience sampling method [ 26 ], in which every participant (160 Caucasian adult non-obese women) was observed on a large num- ber of meals occurring over a short period of time.
This method allowed us to examine each partici- pant’s food choice at a meal level, account for the nutritional quality of each meal in terms of its devi- ance from one’s baseline eating pattern, and to map the relationship between emotional states and food choice. During 10 observation days, participants were asked to report 6 times a day on their momen- tary emotional states (see Table 3.1 for the mea- sured emotion items) and on their eating behavior.
Participants were asked to indicate the nutritional quality for each meal in a relative form compared to their usual (baseline) pattern in the same meal occasion (healthier, less healthy, vs. baseline meal). Participants indicated the location of the meal, that is whether the meal episode had been taken at home or away-from- home (see Table 3.2 for the frequencies of observed meals).
Table 3.1 Emotional factor structure
Factor components Cronbach’s alpha Emotion items
General positive emotions 0.88 Joyful Happy Elated Amused
Optimistic Hopeful Encouraged Fulfi lled Accomplished
Warmhearted Loving Sentimental
Positive emotions—calm 0.78 Serene Calm Peaceful Contended
General negative emotions 0.82 Frustrated Annoyed Angry
Miserable Sad Depressed
Negative emotions—shame 0.60 Ashamed Guilty Embarrassed
Negative emotions—anxiety 0.74 Nervous Tense Worried
Participants reported their momentary emotional states for every episode on a 28-item scale of emotions adapted from the Consumption Emotions Set. Participants were asked to indicate the degree to which they were feeling each emotion at that present moment by placing a mark on a 15-cm visual analog scale (rated from “not at all” to “very much”). Factor structure was extracted based on Chain-P factor analysis (Factor Extraction Method: Principal Component Analysis.
Rotation Method: Varimax with Kaiser Normalization)
3 An Evidence-Based Approach to the Nutritional Quality of Home Meals…
In the examination of the post-meal affective states, expectations for the higher general rein- forcing value of eating at home vs. away-from- home and for a stronger effect in the specifi c case of healthy meals were supported. Specifi cally, participants rated higher on calm feeling and less anxiety across all meals at home compared to away-from-home meals. Moreover, only at home, having healthier meals resulted in more positive emotions compared to baseline meals, and no such facilitation effect was found for meals eaten away-from-home (see Fig. 3.1 ). In fact, for away- from-home meals, consuming healthier meals
Table 3.2 The frequencies (odds ratios) of reported nutritional quality for home meals and away-from-home meals
Nutritional quality
Healthier a Baseline Less healthy b Away from home 167 (0.29) 568 174 (0.31) Home 345 (0.18) 1,903 311 (0.16)
Total 512 2,471 485
Separated for home and away-from-home settings, this table shows the number of episodes that participants reported as having baseline, healthier than usual, and less healthy than usual meals
a Odds ratios in this column are based on healthier/baseline b Odds ratios in this column are based on unhealthy/baseline
Fig. 3.1 ( a ) General positive emotions. ( b ) Positive emotions—calm. Means of post-meal positive emotions after home vs. away-from-home meals with different nutritional quality. Marginal means reported in this table are for demonstration purpose. Hypotheses were tested by hierarchical linear models, in which the day-centered
emotion scores (the deviation from day-level mean) for each meal were explained by the location (home vs. away from home), nutritional quality, and the interaction between them, controlled by social context (eat alone vs.
with others) and meal size (larger than usual, baseline, or less than usual)
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was associated with more negative emotions, compared to baseline meals (see Fig. 3.2 ). For the analyses of premeal emotional states as a trigger of healthy eating, the relative nutritional quality of a given meal (healthier, baseline, or less healthy) was predicted by meal location and the emotions reported before the meal. Particularly, the results supported the proposition that more positive emotional experiences precede healthier eating choices in a home setting. Specifi cally at home, more intense premeal positive emotions
were predictive of higher likelihood of choosing a healthier meal over baseline meal, while for away-from-home meals, premeal positive emo- tions showed no effect on the nutritional quality of meals chosen.
As a further source of evidence to paving the way to a more theoretical understanding of positive emotional reinforcing and food, we next present evidence of the importance of parent/child attachment, most of it happening in a home set- ting, which is also linked to healthier eating.
Fig. 3.2 ( a ) General negative emotions. ( b ) Negative emotions—anxiety. Means of post-meal negative emo- tions after home vs. away-from-home meals with different nutritional quality. Marginal means reported in this table are for demonstration purpose. Hypotheses were tested by hierarchical linear models, in which the day-centered
emotion scores (the deviation from day-level mean) for each meal were explained by the location (home vs. away from home), nutritional quality, and the interaction between them, controlled by social context (eat alone vs.
with others) and meal size (larger than usual, baseline, or less than usual)
3 An Evidence-Based Approach to the Nutritional Quality of Home Meals…