Nutrient adequacy of Japanese schoolchildren on days with and without a school lunch by household income

Chika Horikawa; Nobuko Murayama; Hiromi Ishida; Taeko Yamamoto; Sayaka Hazano; Akemi Nakanishi; Yumi Arai; Miho Nozue; Yukiko Yoshioka; Saori Saito; Aya Abe

doi:10.29219/fnr.v64.5377

Nutrient adequacy of Japanese schoolchildren on days with and without a school lunch by household income

Food Nutr Res. 2020 Dec 11:64. doi: 10.29219/fnr.v64.5377. eCollection 2020.

Authors

Affiliations

¹ Department of Health and Nutrition, University of Niigata Prefecture, Niigata, Japan.
² Department of Applied Nutrition, Kagawa Nutrition University, Saitama, Japan.
³ Department of Nutrition, Kanagawa University of Human Services, Kanagawa, Japan.
⁴ Department of Health and Nutrition, Matsumoto University, Nagano, Japan.
⁵ Department of Health and Nutritional Sciences, Tokoha University, Shizuoka, Japan.
⁶ Department of Nutritional Management, Sagami Women's University, Kanagawa, Japan.
⁷ Department of Health and Dietetics, Teikyo Heisei University, Tokyo, Japan.
⁸ Graduate School of Humanities, Tokyo Metropolitan University, Tokyo, Japan.

Abstract

Background: Evidence for whether the nutrient intakes of Japanese schoolchildren differ according to household income is sparse.

Objective: We investigated the role of school lunches for nutrient adequacy among Japanese primary school children using dietary reference intakes in a cross-sectional survey.

Design: Participants were 10- to 11-year-old (5th grade) children from 19 public primary schools in four prefectures of East Japan, and 836 children were analyzed. The participants completed 24-h dietary records with photographs of their meals for 4 consecutive days, composed of 2 days with and 2 days without a school lunch. -Children's household income was obtained from questionnaires that were completed by the participants' guardians and divided into the following three categories: low (0.2236-2.2361 million yen; n = 319), middle (2.3333-2.8868 million yen; n = 194), and high (3.1305-6.3640 million yen; n = 323). Logistic regression analyses were used to estimate the odds ratios for whether participants had poor nutrient intakes, with adjustment for confounders.

Results: On days without a school lunch, the prevalence of nutrient shortages was significantly higher compared with those on days with a school lunch for most macro- and micronutrients among all three levels of household income. Children from low-income households had higher rates of nutrient shortages for vitamin B₆, pantothenic acid, K, Mg, P, Fe, and Zn than those from middle-income households on days without a school lunch (P = 0.004, 0.001, 0.001, 0.006, 0.037, <0.001, and 0.015, respectively), but those differences were not significant on days with a school lunch.

Conclusion: The findings suggest that school lunches are important for achieving adequate nutrient intakes in schoolchildren and reduce disparities of adequate nutrient intake by household income levels.

Keywords: Japan; dietary reference intakes; household income; nutrient adequacy; schoolchildren.