Dietary Modification - Mediterranean Diet

SCOPE: This study assessed plasmatic antioxidant capabilities and xanthine oxidase activity in metabolic syndrome (MetS) patients after 5 years intervention with Mediterranean Diet (MeDiet) supplemented with extra-virgin olive oil (MeDiet+EVOO) or with nuts or with low-fat diet (the PREDIMED study).

METHODS AND RESULTS: 75 participants were randomly selected. Daily energy and nutrient intake were assessed with a validated 137-item food frequency questionnaire, and adherence to the MeDiet was assessed using a 14-item questionnaire. Catalase, superoxide dismutase, myeloperoxidase, xanthine oxidase activities and protein levels, and protein carbonyl derivatives, nitrotyrosine, nitrite and nitrate levels were determined in overnight fasting venous blood samples. The plasma activity and protein levels of superoxide dismutase and catalase were significantly higher and xanthine oxidase activity lower in MeDiet+EVOO and MeDiet+nuts than in the control group. Participants in both MeDiet groups showed higher plasma nitrate levels than in the control group. Adherence to the MeDiet showed a positive correlation with superoxide dismutase and catalase plasma antioxidant activities.

CONCLUSION: A MeDiet enriched with either virgin olive oil or nuts enhances the plasma antioxidant capabilities and decreases xanthine oxidase activity in patients with the metabolic syndrome but we did not observe changes in myeloperoxidase or markers of oxidative damage. This article is protected by copyright. All rights reserved.