Effect: Cancer, Wrinkles, Vision Problems
You'd really have to be living in the dark not to know the value of the largest object in our solar system. Yet we also know that that bright little bugger can be a real sun of a gun. How do the sun's UV rays cause damage? One way is through connective-tissue breakdown. UV radiation causes the structural protein of our skin, collagen, to break down and disables our ability to repair damage. Another way sun ages our skin is through the formation of free radicals—those aggressive charged compounds that damage cells and break down collagen as well. Free radicals can cause cancer by changing our DNA and preventing our body from repairing it.
But the flip side is that we also really need UV rays. Natural sunlight creates active vitamin D, which we need for bone health, since it helps regulate calcium. It also helps ensure the proper function of the heart and nervous systems. This good-and-bad argument is really another example of being balanced. As is the case with many things we've covered, finding the perfect equilibrium is one of the real secrets to slowing the aging process.
Major Ager 12: Disuse Atrophy
Effect: Weakening Limbs and Bones
We've all heard the "use it or lose it" mantra before. The principle? If you let your body parts shrivel up and die, they'll be happy to take you up on your offer. The reason? Your body is too efficient to waste energy feeding limbs and organs that aren't being used. So if you ain't using it, then your body says you're losing it. And the nerves that help control those limbs and organs will wilt away too. This mechanism of aging—disuse atrophy—is a classic example of resource allocation. If your body knows that you're using crutches instead of quadriceps, then it figures, forget this, I'll put energy elsewhere—and so your leg muscles atrophy when you don't use them for long periods. We need to put our bodies to work in our lives: We need to work our muscles, our brains, and virtually every other organ and system in our bodies to make them stronger for longer.
Major Ager 13: Wear and Tear
Effect: Age-Related Conditions like Hearing Loss
When you grind down your body simply by the act of living—whether it be your joints or your ears—your body is going to experience some kind of damage. It's the slow churning away at the efficiency and productivity of our body's systems that causes many of the ailments we associate with aging. But our own behavior and choices play a part too! Constantly listening to your iPod at full blast? Then expect hearing loss later in life! What we have to be careful about is falling into the trap of thinking that deterioration is normal when it comes to aging. Just because it's common to creak like a haunted house as we get older doesn't mean it's inevitable; our bodies ought to be able to make those necessary repairs. It's when we are unable to make those repairs—be it due to chronic disease or damaged DNA—that we slip into what most of us think of as, simply, old age.
Major Ager 14: Unforced Errors
Much of aging certainly is about preventing the decrease in quality of life from chronic disease and long-term wear and tear. But the ultimate form of aging is the kind of that bypasses all the details and kills us off immediately: a car crash, a fall from a cliff, or a freak encounter with a rabid antelope. Most of us like to write off accidents as unfortunate circumstances of fate, but many accidents are very preventable and not really the end result of some cosmic master plan of evil. When it comes to accidents and unforced errors, the big picture is this: It's all about leverage points—tipping life into your favor by doing the things that make your body better equipped to handle the unexpected things that will be hurled your way.
It means making sound decisions in life (non-slip mat in the shower, helmet when you’re riding a bike) to stack the odds in your favor. It means knowing where the trouble spots may be, so you can plan to avoid them—and cope with them if you can't.
Still looking for answers? 10 more sneaky aging culprits