Abstract
The low-grade inflammation seen with aging is noted particularly in subjects with the metabolic syndrome of aging. Insulin resistance, obesity/abdominal obesity, and risks for many age-related diseases characterize this common syndrome. It is becoming clear that this increased adipose tissue is not simply a reservoir for excess nutrients, but rather an active and dynamic organ capable of expressing several cytokines and other fat-derived peptides (FDP). Some, but not all, FDP may have a role in development of the metabolic syndrome but there is no evidence that these FDP are causing inflammation directly. We suggest that high levels of inflammatory peptides are markers for obesity/abdominal obesity seen with aging, but some may not necessarily have a causative role in the development of inflammation.