Plant seed extract compositions obtained by washing a defatted plant seed with water, and extracting the resulting washed seed product with an organic solvent and safflower seed extract compositions wherein the weight ratio of the total content of (a) p-coumaroylserotonin, feruloylserotonin, p-coumaroylserotonin glycoside, and feruloylserotonin glycoside to (b) 2-hydroxyarctiin is 1:0.01 to 0.2, are effective for reducing the risk of developing atherosclerosis and diseases caused by atherosclerosis and also exhibit a reduced tendency to cause diarrhea.