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The follow-up of the Mediterranean Diet (MD) has been associated with lower mortality and morbidity from cardiovascular diseases. However, it is important to evaluate the scientific evidence provided by published articles. Therefore, in order to analyze the literature on the overall effects of MD on intermediate and final disease phenotypes, we reviewed the findings from 30 selected experimental and observational studies. We analyzed the effect of MD on all-cause mortality, cardiovascular mortality, recurrence of cardiovascular events, lipid profile, inflammatory markers, blood pressure and fasting blood glucose levels. In general, MD was found to have beneficial effects on final and intermediate disease phenotypes. However, more randomized, controlled interventional studies on the overall effects of MD offering the highest level of scientific evidence are needed before adequate dietary recommendations concerning the primary prevention of cardiovascular disease can be given., (Copyright 2008 Elsevier España, S.L. All rights reserved.)

The term conjugated linoleic acid (CLA) concerns a group of isomers of linoleic acid, which are characterized by having conjugated double bonds in several positions and conformations. CLA is found naturally in some foods, but since CLA was first held to cause beneficial effects on various health-related issues, many investigations have been conducted to elucidate the effects of dietary supplementation with CLA. The effects of CLA on lipid profiles on animals have been extensively studied, and there is sound evidence of its benefits in blood metabolic markers. However, clinical trials in humans have provided ambiguous results. The aim of this review was to gather up-to-date available data about the effects of CLA on human lipid profile. Although most studies did not show any significant effect in none of the studied variables, some trials reported both beneficial and detrimental effects on total cholesterol, LDL-c, HDL-c, atherogenic index, triglycerides and lipoprotein(a). This discrepancy could be due to differences in dosage, isomer composition, duration of the study, placebo and participating subjects, among others. However, studies with a duration of two weeks, carried out using a mix of equal amounts of the two main CLA isomers (9-cis, 11-trans and 10-trans, 12-cis) and with doses of 3 to 4 grams per day, seem to offer the most beneficial results.

Oxidative stress is related to an imbalance between the production of reactive species and the antioxidant defenses. In essence, oxidative stress has been defined as a disturbance in the pro-oxidant/antioxidant balance, leading to potential damage. It has been suggested that oxidative stress is involved in the etiology of several chronic diseases including cardiovascular disease, diabetes, cancer and neurodegenerative processes. The antioxidant defenses include nonenzymatic (especially dietary antioxidants) and antioxidant enzymes. Vitamins, minerals and phytochemicals (polyphenols and carotenoids) are among the major dietary antioxidants. The assessment of oxidative stress status though specific biomarkers has acquired great importance. The major biomarkers include the products of the attack of free radicals and reactive species to various substrates: lipids, proteins and nucleic acids. Measurement of antioxidant capacity may also involve the assessment of specific oxidative stress biomarkers. Most of the studies that have examined the association between diet and oxidative stress consider the effects of antioxidant supplements (vitamins and minerals), drinks and foods with bioactive compounds or dietary patterns on oxidative stress biomarkers. Some of these studies have demonstrated beneficial results on oxidative stress markers. However, the role of diet on oxidative stress biomarkers remains unclear and represents a potentially fruitful area for further research in the health area.

The Objective: [corrected] of this article is to review biomarkers that have been suggested in recent years as the link between inflammation, obesity and associated co-morbidities, as well as some questions that yet remain unclear. Increasing evidence indicates the important role of inflammation in the etiology of major public health problems. In the last years, several studies have proposed that obesity might be a inflammatory disorder. In addition, oxidative stress has been suggested as a potential inductor of inflammatory status and susceptibility to obesity and related disorders. Several biomarkers are being suggested as the link between obesity, insulin resistance, cardiovascular disease and metabolic syndrome, such as tumor necrosis factor alfa, interleukin-6 and -18, angiotensinogen, transforming grow factor beta, plasminogen activator inhibitor-1, leptin, resistin, C-reactive protein, serum amyloid A, sialic acid, fibrinogen, markers of endothelial dysfunction (von Willebrand factor, ICAMs, VCAMs), complement factor 3, haptoglobin, Zinc-alpha2-glycoprotein, eotaxin, visfatin, apelin, alpha1-antitrypsin, vaspin, omentin, retinol binding protein 4, ceruloplasmin, adiponectin and desnutrin. Some of this biomarkers are good predictors of cardiovascular risk (plasminogen activator inhibitor-1, sialic acid, fribrinogen, complement factor 3, C-reactive protein), adiposity (leptin, visfatin, resistin, haptoglobin) and/or insulin resistance (sialic acid, C-reactive protein, plasminogen activator inhibitor-1, von Willebrand factor). However, it is currently unclear the role of many of them concerning inflammatory processes in humans, as well as the factors involved in their regulation.