Date of Award


Degree Type


Degree Name

Doctor of Philosophy (PhD)


Hospitality and Tourism Management

Committee Chair

Barbara Almanza

Committee Member 1

Carl Behnke

Committee Member 2

Chun-Hung (Hugo) Tang

Committee Member 3

Richard Ghiselli


Increased portion size of commonly consumed foods has been considered a strong environmental factor contributing to food overconsumption. Regulatory interventions to reduce portion sizes in restaurants, however, are likely to be opposed by the foodservice industry due to concerns that reduced portions may negatively affect consumers’ value perception. These interventions may also be considered as paternalistic by some consumers. Three studies were conducted to examine possible approaches to the “portion inflation” problem from different perspectives, with the intention to seek balance between public health benefits and business interests, and between corporate responsibility and consumer responsibility.

In study one, two quasi-experiments were conducted to investigate how changes in portion or plate size would affect restaurant consumers’ perceived reasonable price of the food and their willingness to pay. Results showed that the effects of portion size on the participants’ perceived value of the food largely depended on the participants’ perceived quality of the food and their purchase intention. Reduced portion size did not compromise the participants’ value perception when the food was perceived as having high quality or when the participants had high purchase intention.

Study two explored the opportunities for restaurants to create more value to consumers by providing higher quality food in moderate portions. A K-Means cluster analysis was conducted to classify a sample of 613 participants based on their preferences for seven food quality attributes (taste, texture, aroma, appearance, and the use of natural, local, and organic ingredients) relative to quantity (portion size). Five restaurant consumer segments were identified: sensory-oriented consumers, taste-oriented organic food consumers, natural and local food consumers, quantity-oriented consumers, and quality-oriented consumers. Gender (p < .001), age (p = .002), and income (p < .001) were strong predictors of segmentation outcome. Quality-oriented and quantity-oriented consumers differed in restaurant consumption patterns.

Study three examined how intuitive eating could contribute to healthier Body Mass Index (BMI) through less inflated perceptions of regular serving size and a focus on food sensory quality rather than quantity. Two variables were tested as potential mediators in the negative association between intuitive eating and BMI: (1) portion size perception; and (2) preference for food sensory quality versus quantity. Results showed that preference for food sensory quality (versus quantity) was positively associated with intuitive eating (p < .001) and negatively associated with BMI (p < .001); perception that regular serving sizes in restaurants were too small was negatively associated with intuitive eating (p < .001) and positively associated with BMI (p = .05), adjusted for gender, age, and income. Preference for food sensory quality (versus quantity) partially mediated the relationship between intuitive eating and BMI (b = −0.21, 95% CI [−0.39, −0.02], p = .03). The proposed mediation effect of portion size perception was not significant.

Findings of the current research suggested opportunities for foodservice establishments to reduce excessive portion sizes and therefore food cost and plate waste, while maintaining or creating more value for consumers through improved food quality. Findings also suggested that a focus on the sensory quality of food and an improved awareness of “portion distortion” could potentially contribute to healthier eating behaviors and lower BMI.

Available for download on Monday, July 01, 2024