Influence of Dietary and Non-Dietary Factors on Urticaria

Abstract

Urticaria is a significant public health concern and common dermatological disease characterized by recurrent episodes of itching, redness, and wheals, which can be triggered by dietary and non-dietary factors, including food intake, psychological stress, vitamin D deficiency, and heat exposure, and have been implicated in triggering or exacerbating symptoms. A cross-sectional, self-reported survey was conducted in Zawia City, Libya, between November 2025 and February 2026 among patients attending multiple centers, including Alshorouk Clinic and Al Mutrad Hospital, as well as students from the Faculty of Medical Technology. The study aimed to identify the most commonly reported food allergens associated with urticaria and to evaluate the influence of non-dietary factors, including psychological stress, heat exposure, and vitamin D deficiency. Of 200 respondents with urticarial disease who completed the questionnaire, 92% were female. Nearly half of the participants had daily wheals, with half of the participants reporting three or more episodes per week; more than half of the participants reported a duration of wheals was 1- 12 h. Regarding associated symptoms, itching was reported by the majority of participants, followed by Redness and Angioedema. A significantly higher association between vitamin D deficiency and monthly episodes compared to those with normal levels (median: 4 vs 2 episodes, Mann-Whitney U test, p <0.001). Furthermore, severe itching was significantly associated with both spicy food consumption and psychological stress p <0.001. Environmental exposure was identified as a contributing factor, with 112 of the participants (56%) reporting heat exposure. In conclusion, urticaria is impacted by multiple dietary and non-dietary factors. Vitamin D deficiency, heat exposure, spicy food, and psychological stress were associated with more frequent urticaria episodes, while Food additives, Heavy meals, Tomatoes, and dairy were identified as important symptom triggers. Identifying these factors may help improve symptom control, and further studies are recommended to evaluate lifestyle.