Described is a fat or oil composition which comprises at least 35 wt % of a diacylglycerol, the constituent fatty acids of said diacylglycerol satisfying the following equation: (an amount of a cis-form unsaturated fatty acid)/(an amount of a saturated fatty acid+an amount of a trans-form unsaturated fatty acid).gtoreq.6, the usual intake of which as an edible oil makes it possible to reduce arteriosclerotic factors in blood, leading to the prevention of arteriosclerosis, and furthermore, various degenerative diseases.