The metabolic syndrome: definition, global impact, and pathophysiology

The metabolic syndrome (MS) is a cluster of metabolic derangements that are associated with primary disturbances in adipose tissue. Abnormal visceral fat accumulates from physical inactivity and excess calories in genetically susceptible individuals. This increased adipocyte mass acts as an endocrine organ and communicates with other organ systems via increases in inflammatory cytokines. The resulting disorders define MS as increased waist circumference, decreased serum high-density lipoprotein, and increased serum triglyceride levels, hypertension, and insulin resistance. MS accounts for the majority of cardiovascular disease risk in the U.S. population. Dietary interventions, such as the Mediterranean diet, have been shown to improve these metabolic derangements. Many substances found in these diets are being investigated as specific therapies for MS, and when scientific substantiation is lacking, they may be considered as part of complementary and alternative medicine (CAM). However, as scientific evidence accumulates, these CAM treatments may become part of conventional medicine. This review will scrutinize the emerging evidence behind many, though not all, CAM treatments currently thought to target the various derangements found in MS.