Does the association between patterns of fruit and vegetables and metabolic syndrome incidence vary according to lifestyle factors and socioeconomic status?

BACKGROUND AND AIMS: The aim of this study is to investigate the association between the identified patterns of fruits and vegetables and metabolic syndrome (MetS) incidence, and to investigate whether lifestyle factors and socioeconomic status modify the effect of the patterns on MetS risk. METHODS AND RESULTS: We prospectively studied 1915 participants of the Tehran Lipid and Glucose Study, who were aged 19-74 years and followed up for dietary assessment using a validated, semi-quantitative food frequency questionnaire. After adjustment for confounding factors, total vegetable intake was inversely related to the risk of MetS. Total fruit and total fruit and vegetable were not associated with MetS risk. We identified four major patterns of fruits and vegetables by factor analysis: "fresh fruit pattern", "vegetable pattern", "dried fruit and cruciferous vegetable pattern", and "potatoes and fruit juice pattern". "Vegetable pattern" was negatively associated with MetS risk, and "potatoes and fruit juice pattern" increased the risk of MetS. Among participants with weight gain <7% during follow-up, all four identified patterns reduced MetS risk. When stratified by smoking, "vegetable pattern" and "dried Fruit and cruciferous vegetable pattern" lowered MetS risk among non-smokers. Stratification based on education resulted in MetS risk reduction across tertiles of "fresh fruit pattern" and "vegetable pattern". First and second tertiles of "dried fruit and cruciferous vegetable pattern" lowered MetS risk among educated participants, compared to the reference. CONCLUSIONS: The reduction in MetS risk caused by fruits and vegetables intake depends on the modifying effect of lifestyle and socioeconomic factors.