Cod liver oil does not soften blood vessels. Cod liver oil mainly contains vitamin A and vitamin D, which can be used to treat vitamin A and vitamin D deficiency, but it does not soften blood vessels. To soften blood vessels, we should start from the causes of atherosclerosis, such as strict cessation of smoking, including second-hand smoke, control of blood pressure, blood lipids, blood sugar and weight, and pay attention to a healthy diet in general, and it is recommended to refer to the structure and composition of the Mediterranean diet with good calorie calculation. In order to slow down the progression of atherosclerosis and keep the blood vessels in good condition, you should take active physical exercise and choose your own suitable exercise program and stick to it.