Cultural Moderation of Unconscious Hedonic Responses to Food

Psychosocial Experiences Related to Dietary Behavior of Japanese Lactating Women: A Qualitative Study

Adequate dietary intake during the lactation period is important for breast milk components, postpartum recovery, and physical and mental health. This study aimed to clarify the psychosocial experiences related to dietary behavior around one month postpartum among Japanese lactating women. Semi-structured interviews were conducted with 18 women between February and June 2022 in Osaka, Japan. The data were analyzed using qualitative descriptive approaches. Four core categories were identified. All participants had a [desire to have healthy meals for themselves or their families] to improve their postpartum health, regain their pre-pregnancy body shape, produce sufficient and good-quality breast milk, and keep their families healthy. Some participants, who had [subjective difficulties in getting information on diet and preparing meals] due to insufficient or complicated information and viewing meal preparation as a burden, used [services and support regarding their postpartum diet] to alleviate these difficulties. They had [postpartum-specific appetite and dietary views], including an increased appetite triggered by breastfeeding and postpartum stress and the effects of the dietary changes during pregnancy. Some of these psychosocial experiences were influenced by Japanese traditional customs in the postpartum period and familiar food preferences in the Japanese. Healthcare professionals should consider these experiences when providing tailored dietary guidance.

Chili pepper preference development and its impact on dietary intake: A narrative review

A preference for chili pepper can be an acquired taste. The contrast between a chili lover and a hater illustrates the complexities involved in forming an appreciation for food that evokes a fiery pain sensation. This narrative review aims to understand the factors behind chili pepper preference formation across the life course and how individual chili pepper preferences can impact eating behaviors and dietary intake. This review was conducted using three databases, yielding 38 included articles. Results suggest five determinants of chili pepper preferences: culture, exposure, gender, genetics, and personality. Collective findings indicate that the strongest influences on preference acquisition include the individual environment from childhood to adulthood and repeated exposure to spicy flavors. With frequent exposure to spicy food, the perceived burn becomes less intense. Culture also influences exposure to chili peppers, with the highest consumption patterns seen within Mexico and some Asia countries. Additionally, males reported having a stronger preference for spicy foods than females. Twin studies illustrated that genetics influenced spicy taste preferences, underscoring the complexity of developing individual taste preferences. As for the impact of capsaicin-containing food on individual eating behaviors and dietary behaviors, appetite effects depend on the dose of capsaicin consumed, but three studies found a change in sensory desires for sweet and fatty foods after finishing a capsaicin-containing dish. Inconsistent results were reported for chili pepper's effects on hunger and satiety after consumption, but changes in specific food desires were observed. The impact of chili pepper on appetite and calories consumed was inconsistent, but the greater amount of capsaicin ingested, the greater the effect. Capsaicin's potential to be used for weight control needs to be further reviewed. In conclusion, evidence suggests that chili pepper preferences may be linked to innate and environmental aspects such as an individual's culture, gender, and genetics. Extrinsic factors like repeated exposure may increase the liking for spicy foods.

Evaluation of energy density and macronutrients after extremely brief time exposure

Many food decisions are made rapidly and without reflective processing. The ability to determine nutritional information accurately is a precursor of food decisions and is important for a healthy diet and weight management. However, little is known about the cognitive evaluation of food attributes based on visual information in relation to assessing nutritional content. We investigated the accuracy of visual encoding of nutritional information after brief and extended time exposures to food images. The following questions were addressed: (1) how accurately do people estimate energy and macronutrients after brief exposure to food images, and (2) how does estimation accuracy change with time exposure and the type of nutritional information? Participants were first asked to rate the energy density (calories) and macronutrient content (carbohydrates/fat/protein) of different sets of food images under three time conditions (97, 500 or 1000 ms) and then asked to perform the task with no time constraints. We calculated estimation accuracy by computing the correlations between estimated and actual nutritional information for each time exposure and compared estimation accuracy with respect to the type of nutritional information and the exposure time. The estimated and actual energy densities and individual macronutrient content were significantly correlated, even after a brief exposure time (97 ms). The degree of accuracy of the estimations did not differ with additional time exposure, suggesting that <100 ms was sufficient to predict the energy and macronutrients from food images. Additionally, carbohydrate estimates were less accurate than the estimates of other nutritional variables (proteins, fat and calories), regardless of the exposure time. These results revealed rapid and accurate assessment of food attributes based on visual information and the accuracy of visual encoding of nutritional information after brief and extended time exposure to food imagery.

Facial EMG Activity Is Associated with Hedonic Experiences but not Nutritional Values While Viewing Food Images

The physiological correlates of hedonic/emotional experiences to visual food stimuli are of theoretical and practical interest. Previous psychophysiological studies have shown that facial electromyography (EMG) signals were related to subjective hedonic ratings in response to food images. However, because other data showed positive correlations between hedonic ratings and objective nutritional values of food, whether the facial EMG reactions to food images could reflect the hedonic evaluation or nutritional assessment of food remains unknown. To address this issue, we measured subjective hedonic ratings (liking, wanting, valence, and arousal) and physiological signals (facial EMG of the corrugator supercilii, zygomatic major, masseter, and suprahyoid muscles, skin potential responses, and heart rates) while participants observed food images that had objective nutritional information (caloric, carbohydrate, fat, and protein contents). The results revealed that zygomatic major EMG activity was positively correlated with ratings of liking, wanting, and valence, but not with any objective nutritional value. These data indicate that facial EMG signals in response to food images reflect subjective hedonic experiences, but not objective nutritional values, associated with the food item.

Cultural differences in food detection

The ability to detect food plays an indispensable role in our survival and wellbeing. Previous psychological studies have revealed that food is detected more rapidly than non-food items. However, whether the detection of food could be modulated by cultural factors remains unknown. We investigated this issue in the present study using a visual search paradigm with Polish and Japanese participants. Photographs of international fast food, domestic Japanese food, or kitchen tools were presented alongside images of non-food distractors (cars). Participants were asked to judge whether the stimuli were all identical or not. The reaction time data showed that participants from both cultures detected food more rapidly than kitchen tools. Japanese participants detected fast food more rapidly than Japanese food, whereas Polish participants did not display such differences between food types. These results suggest that rapid detection of food is universal, but is modulated by cultural experiences.

Image database of Japanese food samples with nutrition information

Background

Visual processing of food plays an important role in controlling eating behaviors. Several studies have developed image databases of food to investigate visual food processing. However, few databases include non-Western foods and objective nutrition information on the foods.

Methods

We developed an image database of Japanese food samples that has detailed nutrition information, including calorie, carbohydrate, fat and protein contents. To validate the database, we presented the images, together with Western food images selected from an existing database and had Japanese participants rate their affective (valence, arousal, liking and wanting) and cognitive (naturalness, recognizability and familiarity) appraisals and estimates of nutrition.

Results

The results showed that all affective and cognitive appraisals (except arousal) of the Japanese food images were higher than those of Western food. Correlational analyses found positive associations between the objective nutrition information and subjective estimates of the nutrition information, and between the objective calorie/fat content and affective appraisals.

Conclusions

These data suggest that by using our image database, researchers can investigate the visual processing of Japanese food and the relationships between objective nutrition information and the psychological/neural processing of food.

Facial EMG Correlates of Subjective Hedonic Responses During Food Consumption

An exploration of physiological correlates of subjective hedonic responses while eating food has practical and theoretical significance. Previous psychophysiological studies have suggested that some physiological measures, including facial electromyography (EMG), may correspond to hedonic responses while viewing food images or drinking liquids. However, whether consuming solid food could produce such subjective–physiological concordance remains untested. To investigate this issue, we assessed participants’ subjective ratings of liking, wanting, valence, and arousal while they consumed gel-type food stimuli of various flavors and textures. We additionally measured their physiological signals, including facial EMG from the corrugator supercilii. The results showed that liking, wanting, and valence ratings were negatively correlated with corrugator supercilii EMG activity. Only the liking rating maintained a negative association with corrugator supercilii activity when the other ratings were partialed out. These data suggest that the subjective hedonic experience, specifically the liking state, during food consumption can be objectively assessed using facial EMG signals and may be influenced by such somatic signals.

Body Dissatisfaction, Restrictive, and Bulimic Behaviours Among Young Women: A Polish-Japanese Comparison

The growing number of women, who are characterized by restrictive and bulimic behaviours towards their own body is observed especially in countries influenced by Westernalization. However, there is a lack of cross-cultural studies in this area. The main aim of the present study was to examine the psychological and socio-cultural risk factors for eating disorders in Polish and Japanese women. A cross-sectional research study was conducted among 18- to 29-year old Polish (n = 89) and Japanese (n = 97) women. The variables were measured using the Sociocultural Attitudes Towards Appearance Scale SATAQ-3, and the Eating Disorders Inventory EDI-3. The descriptive and comparative statistics, Spearman's rho, and the stepwise regression analysis were used. The global internalization of socio-cultural standards of body image proved to be a significant predictor of Body Dissatisfaction among Polish and Japanese women. The main analysis showed a significant relation between the Drive for Thinness and Interoceptive Deficits in the group of Japanese women, as well as a correlation between Drive for Thinness and Asceticism in the group of Polish women. The obtained results could improve the prevention aimed the dysfunctional eating behaviours. However, the cultural nuances need to be considered in understanding the risk factors for eating disorders.