Association of the Healthy Eating Index with Metabolic Abnormalities among Middle-Aged Adults Living in Single-Person Households in Korea

This study aimed to analyze the association between the dietary lifestyles and health outcomes among middle-aged (40–64 years old) and elderly (65 years old and older) individuals living alone using the Korean Healthy Eating Index (KHEI). The study was conducted with 1442 participants (475 men and 967 women) aged 40 years and older living in single-person households using the Korea National Health and Nutrition Examination Survey from 2016 to 2018. The KHEI scores were calculated based on the 24-h recall data of dietary intake. Among women living alone, the total KHEI score of the participants aged 40–64 years was 65.92, which was significantly lower than the 70.66 of those aged 65 years and older (p = 0.0152). In addition, the total score in the adequacy domain was significantly lower among the 40~64-year-old group than those aged 65 years and older (p = 0.0011). Among the elderly in single-person households, the odds of diabetes in the T1 group were 2.08 times higher than those in the T3 group according to the KHEI (95% confidence interval: 1.36–3.17). The results of this study are expected to be used as baseline data to establish nutrition, home meal replacement utilization, and health policies for the elderly living alone.