title: Dietary phytochemical index and the risk of insulin resistance and β-cell dysfunction: a prospective approach in Tehran lipid and glucose study.
abstract: BACKGROUND
  In this study, we aimed to investigate the association of dietary phytochemical index (DPI) with insulin resistance, β-cell dysfunction, and insulin sensitivity.
  
  
  METHODS
  This longitudinal study was conducted on 1141 participants of the Tehran Lipid and Glucose Study. Dietary data were collected using a validated semi-quantitative FFQ with 168 food items at baseline and DPI was calculated. Fasting serum insulin and glucose were measured at baseline and again after a 3-year of follow-up.
  
  
  RESULTS
  After 3-years of follow-up, the risk of hyperinsulinemia significantly decreased by 65 (OR = 0.35, 95% CI = 0.21-0.60) and 86% (OR = 0.14, 0.07-0.29), in the third and fourth quartile categories of DPI, respectively. The occurrence of insulin resistance and insulin insensitivity in participants with higher DPI was significantly lower than the others (OR = 0.48, 95% CI = 0.25-0.93 and OR = 0.11, 95% CI = 0.05-0.24, respectively).
  
  
  CONCLUSIONS
  Higher consumption of phytochemical-rich foods may have protective effects against development of insulin resistance.
authors.affiliation: a Nutrition and Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences , Tehran , Iran .
authors.forename: Zahra
authors.initials: Z
authors.lastname: Bahadoran
authors.affiliation: a Nutrition and Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences , Tehran , Iran .
authors.forename: Parvin
authors.initials: P
authors.lastname: Mirmiran
authors.affiliation: b Prevention of Metabolic Disorders Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences , Tehran , Iran , and.
authors.forename: Maryam
authors.initials: M
authors.lastname: Tohidi
authors.affiliation: c Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences , Tehran , Iran.
authors.forename: Fereidoun
authors.initials: F
authors.lastname: Azizi
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D004032:Diet; D002149:Energy Intake; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood / Q000178:diet therapy; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D050417:Insulin-Secreting Cells / Q000187:drug effects* / Q000473:pathology; D007492:Iran; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015596:Nutrition Assessment; D064209:Phytochemicals / Q000008:administration & dosage*; D011446:Prospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires
chemical_list: D001786:Blood Glucose; D007328:Insulin; D064209:Phytochemicals
keywords: Dietary phytochemical index; fasting serum insulin; insulin resistance; β-cell dysfunction