The Major Source of Antioxidants Intake From Typical Diet Among Rural Farmers in North-eastern Japan in the 1990s.

Megumi Tsubota-Utsugi,Jun Watanabe,Tomoyuki Oki,Yoshitaka Tsubono,Takayoshi Ohkubo,Jun Takebayashi

doi:10.2188/jea.je20190237

Abstract

BackgroundPrevious Japanese studies have led to the erroneous conclusion of antioxidant capacity (AOC) intakes of the overall Japanese diet due to limitations in the number and types of food measured, especially in rice and seafood intake. The aims of the study were to construct an AOC database of foods representative of the typical Japanese diet and to clarify the high contributors to AOC intake from the overall diet of the Japanese population.MethodsCommonly consumed foods were estimated using 3-day dietary records (DRs) over the four seasons among 55 men and 58 women in Japan. To generate an AOC database suitable for the typical Japanese diet, hydrophilic (H-)/lipophilic (L-) oxygen radical absorbance capacity (ORAC) values of foods in each food group were measured via validated methods using the food intake rankings. Subsequently, we estimated the AOC intake and the AOC characteristics of a typical Japanese diet.ResultsOf 989 food items consumed by the participants, 189 food items were measured, which covered 78.8% of the total food intake. The most commonly consumed types of antioxidant-containing food were tea, soybean products, coffee, and rice according to H-ORAC, and soybean products, fish and shellfish, vegetables, and algae according to L-ORAC.ConclusionsThe characteristics of high AOC intake in rice and seafood more appropriately reflected the Japanese-style diet. Further studies are expected to clarify the association between food-derived AOC and its role in preventing or ameliorating lifestyle-related diseases.

Highlights

There is increasing awareness regarding the health risks of reactive oxygen species in the body; the ability of the antioxidant capacity (AOC) to prevent or ameliorate various chronic diseases remains controversial.[1,2,3,4,5,6,7] There are several possible explanations for these discrepancies
Even though previous studies reported that AOC data was collected using the “oxygen radical absorbance capacity (ORAC) method,” which is one of the most widely used methods to evaluate AOC,[8] there was large variation in the methods employed in the measurement process
The major contributors to AOC intake according to food group were beverages (46.2%), followed by vegetables (10.7%), grain products (8.9%), beans (8.7%), and fruits (6.8%) for hydrophilic ORAC (H-ORAC); and fish and shellfish (27.2%), followed by seasoning and spices (21.6%), beans (14.7%), vegetables (11.6%), and eggs (5.8%) for L-ORAC

Summary

Introduction

There is increasing awareness regarding the health risks of reactive oxygen species in the body; the ability of the antioxidant capacity (AOC) to prevent or ameliorate various chronic diseases remains controversial.[1,2,3,4,5,6,7] There are several possible explanations for these discrepancies. High AOC intake from a certain food does not necessarily translate to a large contribution of the food to the overall diet. Even though previous studies reported that AOC data was collected using the “oxygen radical absorbance capacity (ORAC) method,” which is one of the most widely used methods to evaluate AOC,[8] there was large variation in the methods employed in the measurement process. Previous Japanese studies have led to the erroneous conclusion of antioxidant capacity (AOC) intakes of the overall Japanese diet due to limitations in the number and types of food measured, especially in rice and seafood intake. The aims of the study were to construct an AOC database of foods representative of the typical Japanese diet and to clarify the high contributors to AOC intake from the overall diet of the Japanese population

Objectives

Methods

Results

Conclusion