People with sickle cell disease can suffer severe pain, bacterial infections and the death of tissue.

VOA: special.2009.12.16

Some tissue death from surgical manipulation, called necrosis, is inevitable after any procedure, though your risks increase dramatically if you're a smoker.

FORBES: Magazine Article

If accidentally swallowed or inhaled, the magnets can pinch internal tissue, causing infection or even death.

WSJ: Retailers recall potentially dangerous magnet sets

In extreme cases, statins can destroy muscle tissue in a way that poisons the body, resulting in death.

FORBES: Merck And Schering-Plough's Zetia OK'd