"The metabolic syndrome, clinically defined by the Adult Treatment Panel III (ATPIII), affects approximately 25% of western adults," Dr. Domenico Girelli, and colleagues from the University of Verona, write. "The metabolic syndrome is closely linked to insulin resistance and implies an increased cardiovascular risk," they note. "Accumulating evidence suggests a link between body iron excess and insulin metabolism."

To further investigate, the researchers examined the prevalence of iron overload in 269 metabolic syndrome patients and 210 controls. The researchers performed laboratory analyses, including high-sensitivity C-reactive protein, and defined a potentially relevant iron overload as ferritin greater than 300 mcg/L in men and greater than 200 mcg/L in women.

"Mean ferritin levels were higher in metabolic syndrome subjects than in control subjects and increased linearly with the increasing number of metabolic syndrome features" (p < 0.001), Dr. Girelli's team reports.