Obesity adversely affects a large array of health outcomes, including coronary heart disease (CHD), other cardiovascular disease (CVD), and diabetes mellitus.1 It is also associated with established cardiovascular risk factors, particularly diabetes and elevated levels of blood pressure and serum cholesterol.1 However, controversies persist as to whether excess weight has additional impact on CVD outcomes beyond its effects on established risk factors.2,3 Direct evidence on this issue is scant. Although obesity has been upgraded from a contributing risk factor to a major modifiable risk factor for CHD,4 risk assessment tools such as the Framingham Risk Score do not include any measure of obesity.5 In clinical settings, patients sometimes ask if they still need to control their weight if their blood pressure and cholesterol levels are not high. Therefore, in light of the worsening obesity epidemic,6 further research is warranted to examine whether obesity carries additional risks in the absence or presence of other major risk factors.