Abstract

Introduction: Obesity and its complications are a major health problem in Iran. The aim of this longitudinal study was to determine whether changes in food patterns were related to abdominal obesity in Tehranian adults of district 13. Material and Methods: A total of 82 men and 124 women, (≥18 years old), were studied between 1999-2001 and 2004-2007. Subjects with abdominal obesity were defined according to ATPIII and WHO guidelines. Dietary intake was assessed by a food frequency questionnaire and two 24-hour dietary recalls. Food groups were determined according to their nutrients contents and previous literature. Food patterns were derived by factor analysis at each time point. The factor scores for each pattern for each subject were calculated by the amount of the intakes of each of the food groups weighted by their factor analysis coefficient matrix the scores were then standardized (mean=0, SD=1). Changes in food pattern, waist circumference (WC) and waist to hip ratio (WHR) were defined by subtracting the factor score for each food pattern and anthropometric measurements in the two time intervals. Results: Men and women were 51±11 and 45±14 years of age at the end of study respectively. During the two periods of the study, mean WC increased from 89.5±10.4 to 97.6±9.1 in men and from 84.8±13.2 to 88.4±12.4 cm in women (p<0.05). Three dietary patterns were identified and named by factor analysis as follows: Healthy (HDP), Western (WDP) and Mix(MDP). In the WDP, salty snacks and sauces had the highest and in the HDP, vegetables had the highest and whole grain had the lowest loading factors in the two study periods. After adjusting for confounding factors better prediction of WC change was obtained in normal individuals with WDP change(β=0.49, R2=0.21, p<0.01) compared with HDP(β=-0.20, R2=0.11, p<0.05). Change in WDP and HDP were related to the WHR change in abdominally obese persons (β=0.21, R2=0.21, p<0.05), (β=-0.23, R2=0.22, p<0.01) respectively. Conclusion: Results of this study indicate that adherence to HDP and decreasing intake of WDP items prevent central adiposity.