Aging is a natural part of life, but that hasn't stopped people from resisting the process. Unfortunately, those efforts have been futile, according to researchers at the University of Arizona, who have shown that it is mathematically impossible to stop aging in multicellular organisms such as humans.
“Aging is mathematically inevitable—really, seriously unavoidable. There is no way out logically, theoretically, mathematically,” said the professor of ecology and evolutionary biology.
Current understanding of the evolution of aging reveals the possibility that aging could be halted if science could find a way to make the selection between organisms perfect. One way to do that could be to use competition between cells to eliminate malfunctioning "slow" cells associated with aging, while leaving other cells intact. But the solution is not that simple, say the researchers.
Two things happen to the body on a cellular level as it ages. One is that cells slow down and start losing function, like when your hair cells stop making pigment, for example. The other thing that happens is that some cells accelerate their growth rate, allowing cancer cells to form. As we age, we all tend to develop cancer cells in the body at some point, even if they don't cause symptoms, the researchers say.
The researchers found that even if natural selection was perfect, aging will still happen, because cancer cells tend to cheat when cells compete. Eventually things deteriorate over time and – according to the math – trying to fix them can make things worse.
“You can slow aging, but you can't stop it.” “We have a mathematical demonstration of why it is impossible to solve both problems. You can solve one problem, but then you're stuck with the other. Things will get worse over time, either way or both:Either all your cells will continue to slow down, or you'll get cancer. And the main reason is that things are going backwards. No matter how much you try to stop this, you can't.”
