Obesity and diabetes mellitus are major health problems worldwide. These pathogenetic conditions greatly increase the chance an individual will suffer cardiovascular disease (CVD). Ingestion of vegetable protein instead of animal protein is thought to be associated with decreased risk of CVD. CVD is the leading cause of mortality worldwide. Many epidemiological and experimental studies have revealed that hypercholesterolemia and elevated low-density lipoprotein (LDL) level are the strongest risk factor for CVD and the pathogenetic role of oxidized LDL in the development of atherosclerotic vascular change. Ingestion of vegetable protein instead of animal protein is thought to be associated with lower risk of CVD. Soy protein contains low methionine and has an amino acid pattern containing a high level of sulfur. The molecular mechanisms of the soy protein diet–enhanced expression of adiponectin remain unclear. One possible mechanism is that the soy protein diet promotes the conversion of large adipocytes to smaller ones exhibiting appropriate adipocytokine-producing activities.