Curcumin compositions are described for administration to healthy subjects, in need thereof, for improving cardiovascular flow. Curcumin compositions described herein can be administered to a subject in an effective dose of 250 mg to 1000 mg, corresponding to about 50 mg to 200 mg curcuminoids, for improvement of endothelial function and reducing risk of cardiovascular diseases. Compositions herein include curcumin either alone or curcumin along with at least one excipient to enhance absorption. Compositions herein improve endothelial function in healthy subjects having FMD value of 5-7% or higher and who are not diagnosed with cardiovascular disease. Compositions herein also improve cardiovascular endothelial function by reducing vascular resistance and enhancing nitric oxide generation in vascular endothelium. Curcumin compositions herein are safe for consumption, possesses enhanced absorption and can be employed for improvement of endothelial function and cardiovascular flow, when administered in an effective dose to a healthy subject, in need thereof.