BACKGROUND:The increasing prevalence of allergic diseases and atopy is affected by sex, age and lifestyle factors. Obesity and excess weight are reported to be potential risk factors for atopy and specifically for asthma symptoms in children and adults.OBJECTIVE:To assess the relation between body mass index (BMI) and allergic diseases in patients of both genders, as well as association of BMI with atopy in healthy subjects.METHODS:BMI (kg/m2), skin-prick test and total serum immunoglobulin E levels were assessed in 139 subjects: 109 were patients with allergic diseases (M to F ratio was 51:58) and 30 were healthy controls (M to F ratio was 6:24).RESULTS:The study population was grouped into asthma, asthmarhinitis, rhinitis, Urticaria oreczema and controls by BMI and sex. Females with the highest BMI were in asthma and urticaria/eczema group. Males with the highest BMI were in asthmarhinitis and urticariaeczema group. High BMI was associated with atopy in both genders of healthy controls. High levels of total IgE were in male allergic patients.CONCLUSION:High BMI was associated with asthma in females, urticaria/eczema in both genders and atopy in both genders of healthy controls. Higher levels of total IgE were concluded in male patients.