Since mitochondria are the energy producers of a cell, if a cell’s mitochondria are defective, any cells that have a high metabolic rate will also be affected. Metabolic poisons can affect specific parts of mitochondrial function. These include such compounds as cyanide and dinitrophenol (an ingredient of early diet drugs). If mitochondria are damaged, they begin to leak free radicals (molecules that have a single unpaired electron in their outer shell) that can alter the DNA.

In addition, because mitochondria have their own DNA, it is also possible for them to be altered by genetic mutations. In fact, mutations in mitochondrial genes are thought to play a role in degenerative neurological diseases such as Parkinson’s and Alzheimer’s.