Validation of a questionnaire of lycopene frequency intake

Abstract

An inverse relationship between some chronic degenerative diseases and plasma lycopene levels has been demonstrated. Dietary intake questionnaires are one of the current methods most used to ascertain dietary patterns and explore their association with the disease risk. The main drawback of their use is the need for previous validation. The purpose of this study was to validate a frequency questionnaire in order to assess the intake of licopene, in the population of the Canary Islands. A food intake frequency questionnaire was designed and administered to 70 patients of the Plastic Surgery Service of the Hospital Universitario Insular de Gran Canaria. Estimated lycopene intake from the food intake frequency questionnaire was examined in relation to plasma lycopene levels, measured by HPLC. The Spearman correlation coefficient between estimated lycopene intake and plasma levels was 0,421 and the validity of the questionnaire was demonstrated. Furthermore, an association between obesity and some pathologies with plasma lycopene levels was observed, although not statistically significant. The food intake frequency questionnaire is valid and it could be useful in epidemiological studies in the population of the Canary Islands.