In developed societies, chronic diseases such as diabetes, obesity, atheros
clerosis and cancer are responsible for most deaths. These ailments have co
mplex causes involving genetic, environmental and nutritional factors. Ther
e is evidence that a group of closely related nuclear receptors, called per
oxisome proliferator-activated receptors (PPARs), may be involved in these
diseases. This, together with the fact that PPAR activity can be modulated
by drugs such as thiazolidinediones and fibrates, has instigated a huge res
earch effort into PPARs(1). Here we present the latest developments in the
PPAR field, with particular emphasis on the physiological function of PPARs
during various nutritional states, and the possible role of PPARs in sever
al chronic diseases.