Abstract
BACKGROUND/OBJECTIVES: This study examined whether the intake pattern of dietary and supplementary vitamin C differs according to the sufficiency of fruit and vegetable (FV) intake and assessed the risk of vitamin C insufficiency according to FV sufficiency and vitamin C supplement use. SUBJECTS/METHODS: Data from 10,464 adults aged ≥ 19 yrs from the 2019-2021 Korea National Health and Nutrition Examination Survey (KNHANES) were analyzed. The participants were categorized into an FV-sufficiency (FVS; ≥ 500 g/day) and FV-insufficiency (FVINS; < 500 g/day) groups. The vitamin C intake from diet, supplements, and major food sources was examined. RESULTS: Approximately 19.6% of young adults, 41.5% of middle-aged adults, and 39.6% of older adults met the recommended intake of FV. Most participants in the FVS group consumed more than 90 mg of dietary vitamin C (90% of the recommended nutrient intake [RNI]), whereas most in the FVINS group consumed less than 50 mg (50% of the RNI). Even among the FVS group, the proportion meeting the RNI ranged from 27% to 37%. In the FVINS group with adequate vitamin C intake, vitamin C was derived predominantly from sugar-sweetened beverages, fruit juice products, and meat. The participants who took vitamin C supplements had a lower risk of vitamin C insufficiency than non-users, regardless of the FV intake status. CONCLUSION: Although the prevalence of vitamin C insufficiency was high, regardless of FV sufficiency, supplementation allowed the FVS and FVINS groups to meet the recommended levels. Nevertheless, the quality of dietary sources remains a concern, with a reliance on less healthy options such as sugar-sweetened beverages and fruit juice products, particularly among young adults. These findings highlight the importance of promoting natural food sources like FV for better diet quality.