Inflammation, oxidative stress and metabolic syndrome: dietary modulation

The metabolic syndrome (MetS) is a cluster of risk factors for the development of cardiovascular disease and type 2 diabetes mellitus. These risk factors include raised blood pressure, dyslipidemia (raised triglycerides and lowered high-density lipoprotein cholesterol), raised fasting glucose, and central obesity. MetS has become a serious public health and clinical problem whose prevalence and incidence are increasing along with the worldwide rise in rates of obesity and sedentary lifestyles. A number of studies have shown that MetS is associated with a state of low-grade inflammation, characterized by abnormal pro-inflammatory cytokine production, increased acute-phase reactants, and activation of a network of inflammatory signalling pathways. Moreover, MetS has also been linked to oxidative stress, a consequence of a reduction in the antioxidant systems and an increase in the production of reactive oxygen species. Nevertheless, agreement exists that dietary intervention may modulate the pro-inflammatory state and lessen oxidative stress related to MetS, thereby decreasing the cardiovascular risk. In this review we address the current available evidence regarding dietary modulation of inflammation and oxidative stress associated with MetS.