Serum urate determines antioxidant capacity in middle-aged men - a controlled, randomized diet and exercise intervention study

Objectives. To study whether advice on diet and/or exercise, given in order to reduce cardiovascular risk factors in middle-aged men, affects the inta ke of antioxidants, urate concentration and the total antioxidant capacity in serum. Design. A 6-month randomized controlled intervention study. Setting. Primary Health Care in Sollentuna, Stockholm, and the Department o f Medicine, Karolinska Hospital, Stockholm, Sweden. Subjects. One hundred and fifty-eight healthy men (46.2 +/- 5.0 years) with moderately raised cardiovascular risk factors. Interventions. Advice on diet (D, n = 40), exercise (E, n = 39), diet and e xercise (DE, n = 39) and a control group (C, n = 39). Main outcome measures. Dietary intake, exercise habits, S-urate and the ant ioxidant capacity in serum (TAC)C). Results. After 6 months, changes in dietary and exercise habits were seen i n all three intervention groups and favourable effects were seen on BMI, wa ist circumference, blood pressure, S-cholesterol and fasting insulin. The i ntake of alpha-tocopherol was decreased in groups D and E (P < 0.01) and be ta-carotene was increased in groups D and DE (P < 0.01), In group DE, the i ntake of vitamin C was increased (P < 0.05). S-urate was reduced in group D from 345 to 325 mu mol L-1 (P < 0.05). No significant changes in TAOC were seen in any group. S-urate and TAOC were correlated (r = 0.58, P < 0.001) and S-urate was correlated to several parameters in the metabolic syndrome. Conclusion. Favourable changes in diet and exercise reduced several cardiov ascular risk factors but did not affect the total antioxidant capacity in s erum. S-urate was a strong determinant of the antioxidant capacity.