The health problem generally known as heart disease is better termed blood vessel disease – because it is caused by blockages in blood vessels. How do these blockages occur? A lesion called atherosclerosis happens when cholesterol, a type of fat, slowly accumulates over many years inside an artery wall. These fatty deposits are not passive lumps – they are active, smoldering centers of inflammation. As these lumps age, cells in the middle die, and release the cholesterol they had absorbed. This process causes the fatty lump to develop a ‘soft center’ with a precariously thin shell. Eventually, inflammation wears the shell away, and the soft ‘porridgey’ center erupts rapidly into the vessel. This signals surrounding blood proteins to rush on to the scene to clump together to form a clot – which closes the channel, and causes a heart attack or stroke.