Homocysteine is one of the most important clinical indicators to detect atherosclerosis. If homocysteine is elevated, it indicates that atherosclerosis is present or there is a potential risk of atherosclerosis. In biochemical tests, if homocysteine is elevated, folic acid tablets should be taken to lower homocysteine and slow down the onset of atherosclerosis. Once atherosclerosis occurs in the blood vessels of the heart, it may manifest as coronary atherosclerosis, and in severe cases, it may manifest as coronary atherosclerotic heart disease, also known as coronary heart disease, which may result in angina pectoris or myocardial infarction. If atherosclerosis occurs in the cerebral arteries, it can manifest as cerebral infarction, hypertension or ischemia and hypoxia in the brain, and atherosclerosis can also occur in other tissues including the renal arteries.