Hair cells can be damaged by exposure to loud noise, which could lead to tinnitus. This can occur gradually as a result of exposure to noises over prolonged periods or may be caused by exposure to louder noises over a shorter period of time. If you are exposed to loud noises, you should always wear ear protection. Find out more about the subject on our How Loud Is Loud article and see if your job or lifestyle could be putting your ears at risk,
Atherosclerosis. With age and buildup of cholesterol and other deposits, major blood vessels close to your middle and inner ear lose some of their elasticity — the ability to flex or expand slightly with each heartbeat. That causes blood flow to become more forceful, making it easier for your ear to detect the beats. You can generally hear this type of tinnitus in both ears.