As cells age, damaged proteins and lipids accumulate within them. Impaired cell parts can send free radicals into the body, and dysfunctional proteins and lipids may break down DNA within cells, causing them to become toxic. Cells usually clean up their own damage through a "housekeeping" process called autophagy. But as the body ages and in people with certain diseases, cells' ability to do this housekeeping becomes less efficient. That means it may be harder for people to recover from cardiac events such as heart attack or other illnesses. Continued at MedicalNewsToday>>