Vitamin C and fibre consumption from fruits and vegetables improves oxidative stress markers in healthy young adults

The aim of the present cross-sectional study was to assess the potential relationships between fruit and vegetable (FV) consumption and some oxidative stress markers in young adults, with particular emphasis on fibre and vitamin C intake. The study enrolled 246 healthy subjects (eighty-eight men and 158 women), with a mean age of 22 (SD 3) years and a mean BMI of 21.9 (SD 2.8) kg/m(2). Dietary intake, anthropometry, blood pressure, lifestyle features and blood biochemical data were assessed with validated procedures. Those subjects in the highest tertile (T) of FV consumption (>= 705 g/d) had statistically lower oxidised LDL (ox-LDL) concentrations as well as higher plasma total antioxidant capacity (TAC) and glutathione peroxidase (GPx) activity (P for trend, < 0.05), after adjusting for sex, age, energy intake, physical activity, smoking, BMI, vitamin supplement use and other confounding factors. Moreover, plasma ox-LDL concentrations showed a decreasing trend and TAC an increasing trend across tertiles of fibre (T3: >= 14 g/d) and vitamin C (T3: >= 150 mg/d) from FV intake, while GPx activity was positively associated with vitamin C intake (P for trend, < 0.05). In conclusion, greater FV consumption was independently associated with reduced ox-LDL as well as increased TAC and GPx activity in healthy young adults, with dietary fibre and vitamin C from FV clearly being implicated in this beneficial relationship.