Effects of the Distribution of Not-for Sale Crops on the Japanese Diet: A Natural Experiment Using Government Statistical Data

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K13037
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 08030:Family and consumer sciences, and culture and living-related
• Research Institution: Gunma University (2021); Takasaki University of Health and Welfare (2018-2020)
• Principal Investigator: Machida Daisuke 群馬大学, 共同教育学部, 准教授 (10622251)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 市場を介さない食物の流通 / 野菜・果物摂取量 / 自然実験

Outline of Final Research Achievements

In order to clarify the impact of the distribution of not-for-sale crops on the dietary habits of the Japanese people, we conducted an analysis using government statistical data. First, we examined the relationship between the amount of non-for-sale fruits and vegetables harvested by prefecture and average prefectural and individual-level vegetable and fruit intakes. Results showed that the amount of vegetables and fruits harvested that were not-for-sale per prefecture was positively associated with prefecture-level and individual-level vegetable and fruit intakes. In addition, a natural experiment was conducted to verify the causal relationship of this association. We examined the case of increased non-for-sale harvest of Chinese cabbage in Nagano Prefecture in 2012. The results confirmed that there may be an effect, but that the effect is very weak.

Free Research Field

食生活学

Academic Significance and Societal Importance of the Research Achievements

本研究の結果、非出荷用の野菜・果物の流通は特定の地域の住民の野菜・果物摂取量に貢献していると推察される。その影響は大きなものではない。しかし、特定の地域の住民では、非出荷用の野菜・果物の流通が野菜・果物摂取量にわずかではあるが確実に貢献していることが見込まれる。したがって、特定の地域ではのような非出荷用食物の流通を緩やかに維持していくことで、その地域の住民の健康的な食生活に良い影響を与えると思われる。