The impact of achieving the national vegetable intake target on cardiovascular disease and healthcare expenditures in Japanese adults: a simulation study, 2021–2031

Abstract

A diet low in vegetables is a notable risk factor for cardiovascular disease (CVD). In Japan, the average daily vegetable intake remains below the Health Japan 21 (Third term) target of 350 g. In this study, we used a simulation model to predict the impact of achieving this national target on CVD outcomes and healthcare expenditures. We developed a Markov model to simulate a closed cohort of 65,660,000 Japanese adults aged 40–79 years in 2021, tracking transitions across six health states reflecting the progression of ischemic heart disease (IHD) and stroke. Using data from existing databases, national survey reports, and previous studies, the model projected the impact of gradually increasing average vegetable intake to 350 g per day from 2021 to 2031 on the number of incident cases, deaths, and national healthcare expenditures associated with IHD and stroke. These results were compared with those of achieving the national salt intake target of 8 g per day. If the 2021 level of the average daily vegetable intake continues for 10 years, the cumulative incidence of IHD and stroke is projected to reach 1.62 million and 1.69 million cases, with 606,651 and 256,916 deaths and national healthcare costs of USD 57.1 billion and USD 101.4 billion, respectively. If the average daily vegetable intake reaches 350 g over 10 years, IHD and stroke incident cases would decrease by 11,852 and 9,945, respectively, with 4,445 fewer IHD deaths and 1,512 fewer stroke deaths. For IHD and stroke, national healthcare expenditures would fall by USD 213 million and USD 386 million, respectively. Compared to achieving the vegetable intake target, meeting the salt intake target would result in 2–3 times greater reductions in the number of incident cases, deaths, and national healthcare expenditures. Although the impact of achieving the national vegetable intake target may be smaller than that of salt reduction, it would still meaningfully contribute to CVD prevention and a reduction in national healthcare expenditures in Japan. Not applicable.