The Validity and Reproducibility of Dietary Non-enzymatic Antioxidant Capacity Estimated by Self-administered Food Frequency Questionnaires.

Ikuko Kashino,Mauro Serafini,Kayo Kurotani,Shamima Akter,Koutatsu Maruyama,Shoichiro Tsugane,Norie Sawada,Manami Inoue,Akiko Nanri,Tetsuya Mizoue,Ayaka Sunami,Motoki Iwasaki,Junko Ishihara

doi:10.2188/jea.je20170063

Abstract

BackgroundHigh dietary non-enzymatic antioxidant capacity (NEAC) has been inversely related to the incidence of degenerative diseases. However, few studies have investigated the validity and reproducibility of dietary NEAC estimated from a food frequency questionnaire (FFQ). We assessed the validity and reproducibility of FFQ-based dietary NEAC against a dietary record (DR).MethodsParticipants were 244 men and 253 women who completed a 28-day DR and FFQs. NEAC for each food item was estimated according to available databases of antioxidant capacity, as measured by ferric reducing-antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and total radical-trapping antioxidant parameter (TRAP). Using Spearman’s rank correlation coefficients (CCs), we assessed the validity for dietary NEACs from a 28-day DR and a FFQ, and the reproducibility for them from two FFQs administered at a 1-year interval. Additionally, joint classification and the Bland-Altman method were applied to assess agreement between the two methods.ResultsRegarding validation, deattenuated CCs for the energy-adjusted overall dietary NEACs between FFQ and DR for FRAP, ORAC, and TRAP were 0.52, 0.54, and 0.52, respectively, for all subjects. Extreme miscategorization rates by joint classification analysis were 2% for FRAP and ORAC and 1% for TRAP. Regarding reproducibility, CCs between the energy-adjusted dietary NEACs from two FFQs were 0.64 for FRAP and 0.65 for ORAC and TRAP.ConclusionThe validity and reproducibility of dietary NEAC of total food from the FFQ were moderate. Estimations of dietary NEAC using FFQ would be useful in studying disease relationships by categorizing habitual dietary NEAC.

Highlights

The human diet contains a wide array of redox-active ingredients, such as vitamins C and E, as well as non-nutrient antioxidants, such as flavonoids, which efficiently modulate cellular antioxidant status and reduce oxidative stress
The contribution of food frequency questionnaire (FFQ)-based non-enzymatic antioxidant capacity (NEAC) levels estimated using all measurement methods decreased in the order of beverages, fruits, and vegetables in energy-adjusted NEACs for men and women combined
The contribution of DRbased NEAC levels decreased in the order of beverages, vegetables, and fruits for ferric reducing-antioxidant power (FRAP) and trapping antioxidant parameter (TRAP), and vegetables, beverages, and fruits for oxygen radical absorbance capacity (ORAC), in both energy-adjusted and -unadjusted NEAC for men and women combined

Summary

Introduction

The human diet contains a wide array of redox-active ingredients, such as vitamins C and E, as well as non-nutrient antioxidants, such as flavonoids, which efficiently modulate cellular antioxidant status and reduce oxidative stress. Dietary patterns and intake of foods rich in antioxidants have demonstrated inverse associations with oxidative stress-related chronic disease risks, including type 2 diabetes[1] and cardiovascular disease (CVD).[2] antioxidants are reported to cooperatively reduce oxidative stress and risk of cancer[3] and mortality[4] through efficient cooperation between components of the redox network. Given the potential for synergistic interaction effects between various dietary and endogenous antioxidants, use of indicator to estimate the overall antioxidant effect of the diet would represent a valuable tool.[5] Non-enzymatic antioxidant capacity (NEAC). High dietary non-enzymatic antioxidant capacity (NEAC) has been inversely related to the incidence of degenerative diseases. Few studies have investigated the validity and reproducibility of dietary NEAC estimated from a food frequency questionnaire (FFQ). We assessed the validity and reproducibility of FFQ-based dietary NEAC against a dietary record (DR)

Objectives

Methods

Results

Conclusion