It's not cellular and molecular damage that causes aging but the accumulation of misrepairs
Two main theories of aging have dominated thinking in this area. On the one hand is the argument that aging is regulated by our genes, an idea that is backed up by various studies showing that some genes can dramatically increase lifespan (if you happen to be a nematode worm, for example).
On the other is the notion that aging is the result of the accumulation of various faults on the cellular and molecular level, caused by environmental factors such as free radicals and molecular cross-linking.
In reality, most researchers think that both mechanisms play an important role.
The new idea from Michelitsch and co relates to this second mechanism. They contend that the accumulation of faults on the cellular and molecular level are certainly involved in aging but are not the mechanism of aging. These faults trigger the body's repair mechanisms, which fix everything up, most of the time.
clipped from: www.technologyreview.com 