Food allergies are a growing health concern, yet scientific understanding of how individuals’ lives are affected by food allergies is limited.The aims of this project were to explore the factors that affect the lives of adults with food allergies; to quantify the level of impact these factors have on daily functioning; to test the role of socio-demographic factors and personality on how food allergies are experienced; and to identify strategies to improve the quality of life of adults with food allergies.A mixed-methods approach was taken, starting with a qualitative method (Study 1), which was used to inform the development of the quantitative method (Study 2).Study 1 explored the experiences of adults with food allergies and the implications of their experiences in terms of consumer vulnerability and impact on health-related quality of life.Focus groups were held with four groups of adults with food allergies to gain an in-depth understanding of how their food allergies affected their lives.The participants experienced consumer vulnerability at different stages of their lives (e.g., during their journey to diagnosis, the post-diagnosis adaptation period, and their ongoing lives with food allergies).Food allergy specific factors that influenced their experience of vulnerability in different contexts included food allergy type and symptom severity (individual characteristics), stage of adaptation to food allergy and level of knowledge acquired (individual states), discrimination/stigmatization, cost and availability of allergen-free food, labelling of food, and the knowledge level of café and restaurant staff (external conditions).Key factors that influenced health-related quality of life included allergen-free eating issues, health care system issues, costs of having a food allergy, effects on well-being, external influences (e.g., others’ lack of awareness), and internal influences (personal growth and adaptation).The unmet needs of food-allergic adults led to risk-taking, increased stress, and social isolation. To extend this investigation, Study 2 quantified the frequency of food allergy issues in daily life and tested the impact of food allergy issues on daily functioning (i.e., experiences of stress, mood, and physical energy).Adults with food allergies (N = 108; 85% women; ages 18 – 87) completed an initial Internet-based survey collecting socio-demographic, personality, and food allergy information.This was followed by a 2-week Internet-based daily diary survey in which participants reported their daily experiences of stress, mood, and physical energy, followed by a 25-item checklist (based on the result of Study 1) about the occurrence of food allergy issues during that day.Analysis of the daily surveys showed several commonly experienced allergy issues.These included negative physical symptoms of food allergy, extra financial cost due to higher food prices, feeling anxious about whether food is safe to eat, trouble with maintaining a healthy diet, and feeling anxious or stressed at social occasions involving food.Multilevel modelling analyses showed that people experienced significantly higher stress and negative mood on days with more allergy issues.Older adults also experienced reduced positive mood and physical energy on days with more allergy issues.Participants living in smaller towns and rural locations experienced more issues per day compared to participants living in cities.Personality traits were found to influence the experience of food allergies in daily life.This study corroborated and extended the findings from Study 1, showing that food allergy-related issues are a common occurrence and source of stress in daily life.Taken together, both Study 1 and Study 2 show that adults with food allergies experience food allergy issues frequently, which has implications for their psychological, social, and physical functioning.Targeting the issues identified in this research will reduce stress in patients with food allergies and improve their overall health and quality of life.