Excess oil (fat) soluble ones can be deleterious as they tend to accumulate in the body fat.
Excess is excess, however not all fats or oils are deleterious. But polyunsaturated fats are the ones to avoid, cause they are unstable and easily oxidized. Particularly omega-6 PUFAs, oxidize into reactive aldehydes and other free radical-like substances, they contribute to the formation of oxidized LDL, which is a key factor in the development of atherosclerotic plaques that can clog arteries.
IMO supplementation with antioxidants helps to protect the arteries from atheroscletrosis. Some antioxidants, such as
vitamins C and E and beta-carotene, are also available as dietary supplements.
