A lot of people think that creaky joints, craggy nails, and cranky bowels are simply part of the deal. You get to live to eighty-something; then, in exchange, you're going to have your fair share of misery along the rest of the way. Horrible being old, eh? Hold on. Yes, there is a trade-off, but it's not that one. If you take a look at every biological process that happens in your body, there's an evolutionary reason why it works that way, and that reason, without fail, is to ensure the survival of the species. That is, evolution has deemed the perpetuation of your genes to be much more important than the perpetuation of your individual life. Your biological processes are designed to protect you only long enough to reproduce and to raise your young. In fact, it wasn't until the mid?twentieth century?at least in developed countries?that human beings could expect to live much beyond their reproductive years.
Those processes that make perfect sense for reproduction may not work in your favor as you get older. That's aging. The systems designed to protect you until you finish reproducing (whether you're actually reproducing is unimportant) can be maladaptive as you age. When you look at aging through the lens of the gene, rather than the lens of the individual, it all makes much more sense. These trade-offs are what we'll occasionally refer to as the YOU-nified theory of aging?the fact that aging isn't some master plan for life but, rather, an offshoot.
2. Aging Isn't About Breaking Down as Much as It Is About Repair
Stuff breaks. Cars, computers, and relationships all have their own breaking points. And to suggest that stuff will not break either through acute injury (a five-alarm fire or a torn knee ligament) or from wear and tear over time (a fifty-year-old roadway or an overused back) would be misleading. While it's obviously important to keep your biological systems from breaking down, the real secret to longevity isn't whether or not you break; it's how well you recover and repair when you do. Our bodies, in fact, weren't designed not to break down (legs as thick as redwoods may not break, but they wouldn't be very nimble). They were designed with a great efficiency and ability to repair themselves.
As with a car, you'll get a lot more mileage out of your body if you perform routine maintenance. Aging is essentially a process in which your cells lose their resilience; they lose their ability to repair damage because the things you might never have heard of (until now), like mitochondria and telomeres, aren't working the way they should. But it's within your power to boost that resilience and keep your vehicle going an extra couple hundred thousand miles.