Changes in Serum Antioxidant Vitamin Levels After Consumption of Korean Diet and American Diet Among Korean Adults: A Randomized Controlled Trial

Abstract Objectives This study aimed to investigate changes in serum antioxidant vitamin levels after consumption of balanced Korean diet (BKD), recommended American diet (RAD), and typical American diet (TAD) among Korean adults from a randomized controlled trial. Methods Among 54 adults aged 25–65 years with body mass index ≥23 kg/m2 and blood LDL-cholesterol ≥120 mg/dL who finished a crossover feeding study conducted between 2015–2017, 16 subjects were selected for analyses of serum β-carotene, retinol, and α-tocopherol levels at baseline and after consumption of each diet for 4 weeks. Serum antioxidant vitamin levels were measured by high-performance liquid chromatography. Results Mean levels of serum β-carotene, retinol, and α-tocopherol at baseline were 0.37, 0.34, and 7.19 mg/L, respectively. After consumption of BKD, increase in serum β-carotene and retinol levels was observed compared to the baseline, whereas α-tocopherol level was decreased. After consumption of RAD, serum β-carotene, retinol, and α-tocopherol levels were increased. However, retinol level was reduced after consumption of TAD. Conclusions This study may provide evidences about effects of diets on antioxidant vitamin levels in human body. Funding Sources This work was carried out with the support of ‘Research Program for Agricultural Science and Technology Development’, National Institute of Agricultural Science, Rural Development Administration, Republic of Korea (Project No. PJ013475022018).