Thirteen-Year Trends in Dietary Patterns among Japanese Adults in the National Health and Nutrition Survey 2003–2015: Continuous Westernization of the Japanese Diet

We examined 13-year trends in dietary patterns, using data from the National Health and Nutrition Survey, Japan 2003&ndash
2015. In repeated, independent cross-sectional studies, dietary intake was assessed with a one-day weighed dietary record in 88,527 Japanese adults aged &ge
20 years. Using principal component analysis based on the daily consumption of 31 food groups, we identified three dietary patterns, the &ldquo
plant food and fish&rdquo
&ldquo
bread and dairy&rdquo
and &ldquo
animal food and oil&rdquo
patterns. In the whole sample, the &ldquo
pattern score decreased while the &ldquo
pattern scores increased. The decreasing trends in the &ldquo
pattern were observed in all subgroups considered. The increasing trends in the &ldquo
pattern were similar across sexes and by current smoking status. However, in terms of age, occupation, and weight status, the increasing trends were only evident in particular subgroups (i.e., age 50&ndash
64 and &ge
65 years
security/transportation/labor occupation and nonworker
and normal weight and overweight participants). For the &ldquo
pattern, the increasing trends were observed in all subgroups, except for the youngest age group (20&ndash
34 years old). This study suggests continuous Westernization of the Japanese diet.