7 Signs of Old Age That Hit Most People When They're Young

7 Fresh, Dewy Skin

If you believe only krokodil enthusiasts and Nazi Grail-hunters have to worry about early-onset skin decay, you're sadly mistaken. In your mid-20s, a time when you're just realizing that eating a pizza a day and sitting on your ass for eight hours straight in an office actually has a negative effect on your health, your skin begins the process of ripping itself apart.

You can blame your deteriorating complexion on the slowed production of collagen and elastin, the two things that keep your skin from making you look like a basset hound. These main building blocks aren't the kind of proteins to stick around for long-term relationships. If you prefer to get all sciency about it, here: "Elastin, the substance that enables skin to snap back into place, has less spring and can even break" as you age.

At some point, your body figures that if you haven't landed a modeling job or a sugar daddy, you probably never will. As such, it decides to pack up all that youthful vitality and make a break for it. There's a genetics-imposed deadline for parlaying your looks into cold, hard cash, and chances are good that if you're reading this article, you've already blown past it. Especially when you also have to contend with no longer having ...

6 Hair In All The Right Places

If right now you're a totally rad male college student with a savage mane of flowing hair, well, enjoy that thicket of pure sex atop your head while you can, because 25 percent of you will start losing it before you turn 30.

Slowly eroding the one symbol of manliness you never had to work to maintain isn't the only dickish thing your body does that involves your follicles. While you're losing the hair you most cherish, hair on other parts of your body actually grows more as you age. So while your head is looking more and more like a smooth stone in a garden, your nose will look like spiders are trying to crawl out of your brain.

The science behind this isn't particularly well understood, but it seems to have something to do with the ever-changing cocktail of hormones that permeates our bodies. Testosterone, in particular, appears to be responsible for hair growth and/or loss, depending on what part of the body you're looking at. And please step away from the steroids; they're not a solution. While they do help with certain types of hair loss if prescribed and applied correctly by a physician, they're not going to return your scalp to its former lush glory.

And it's not just men approaching 30. Decreases in estrogen often lead to rogue chin and lip hair in women who still live in starter apartments adorned with stuffed-animal collections and empty wine boxes waiting for disposal "once the weather improves."

5 A Reliable Immune System

Allergy-rife weaklings are often looked down upon by those of us with iron-clad immune systems. We scoff at the peanut-free dorm dining halls and gluten warning labels, praising our hippy mothers for bathing us in mud puddles as babies and letting us lick park benches to strengthen our immune systems. But we find ourselves much less smug at the sudden appearance of adult-onset food allergies.

All the delicious things you used to enjoy -- ice cream, bread, edamame, peanut butter -- can suddenly start setting off typical allergic reactions ranging from hives to vomiting to anaphylactic shock when you're in your 20s.

And it's not just food you have to worry about. Your immune system can literally decide to start attacking itself for no good reason, too. Rheumatoid arthritis, vitiligo, and the scarily named Graves disease can show up just as you're getting ready to trade in your first car for a slightly less crappy mode of transportation.

Why on Earth would it turn on itself like this? Doctors have a great response to that question: "Who the hell knows?"

They cite everything from sunlight to drug allergies to viruses. If none of those float your boat, just go ahead and blame it all on your parents' shitty genes. Seriously, no one knows. Your guess is as good as anyone else's.

4 A Functioning Esophagus

Acid reflux is not your dad's disease, despite what the commercial rife with sleeveless, middle-aged, Middle-America icons will have you believe. Gastroesophageal reflux disease, or GERD, affects more than 40 percent of Americans, and not just the ones who complain about how their bum knees are affecting the ease of mounting their mid-life-crisis crotch rockets. It can start at any age, even childhood.

OK, so you have acid reflux. You'll have to pop a few of those pastel dollar-store sugar-chalk circles that always ended up at the bottom of your Halloween candy stash to calm the minor irritation. What's the big deal?

Oh, my sweet child, may your blissful ignorance last for all eternity. Acid reflux is not some over-hyped malady easily combated by chowing down on calcium carbonate tablets. GERD is capable of making your esophagus bleed. According to WebMD, "If the bleeding is heavy enough, blood can pass into the digestive tract and show up as dark, tarry stools."

Continued acid exposure in some people causes permanent, irreversible damage, leading to an occasionally pre-cancerous condition known as Barrett's esophagus. It can also lead to gagging and choking in your sleep, causing you to wake up feeling like you can't breathe. That's right -- your body can give you the traumatizing experience of thinking you're going to die due to major organ failure just as you're beginning to realize everyone you went to high school with is getting married and having kids.

3 Mental Stability

In the movies, mental institutions are often filled with disturbed children or aging psychopaths dealing with the long-term effects of age-related mental disorders such as Huntington's disease or Alzheimer's. Unless, of course, you can find a way to fill the scene with sunken-eyed, heroin-chic hotties.

There's a whole slew of mental illnesses that wait to pounce until just after you've realized the degree you just recently earned is more useful as a coaster than a ticket to employment utopia. Principle among these illnesses are schizophrenia and bipolar disorder. Your body is just that much of an asshole that it decides that as soon as you're finally expected to step up to the challenges of clothing yourself with something other than booty shorts, pajama pants, and mascot-emblazoned sweatshirts, the time has arrived for delusions of persecution and hallucinations (preferably of your college mascot).

Forget doing your taxes -- that will have to wait until you've figured out whether "the government" is watching you from the other side of your mirror.

2 Period Regularity

Some women never have the pleasure of bleeding whenever Great Mother Moon is in the right phase. But the rest of us baby-makers get to rejoice over the prospect of spewing forth a deluge of blood on a regular basis for a few decades at least, right? Ain't nothing going to stop this crimson train from arriving on time over ... and over ... and over again ...

You wish it could be that simple! Timely get-togethers with the Red Curse can go haywire long before your first mental debate over the pros and cons of purchasing mom jeans. It's true that hormones start to get wacky as you close in on menopause (just like your fashion sense), and ricocheting levels of estrogen and progesterone can make periods unpredictable. However, your hormones can start holding your body hostage long, long before your uterus spoils. Stress -- which often spikes as you enter the "real world" can throw your reproductive system for a loop.

Speaking of menopause, it's not unheard of for it to start in your early 30s, or even your 20s.

Better get to making those babies soon if you want them, ladies. Planning on waiting until just before your eggs shrivel up during the dreaded "35-year-old Fertility Plunge" is a disaster waiting to happen.

1 Muscles That Work

By now you might be thinking, "Well, I may be a slathering, infertile idiot with the face of a troll by the time I'm 30, but at least I'll be able to lift myself off the couch."

Don't count on it. Age-related sarcopenia (aka, your muscles falling into a deep depression and passing out on the couch in front of the TV, waiting for you to die) can start in your 30s, or even earlier. You're not likely to collapse into a fleshy bag of fat and hair on the eve of your 30th birthday, but you will have to work harder and longer to build muscle than you did in the past. Where once a couple lazy laps around your college track would get your quads and glutes all firm and ripply, eventually you'll have to start running 5Ks a couple of times a week just to avoid traumatizing the dog with your unsightly amount of jiggle as you race to open the door for the food-delivery person.

But who needs muscles, anyway? You're not making your livelihood by lifting concrete blocks or busting through brick walls, so flabby arms and less-than-firm abs aren't exactly going to be the death of you.

Not so fast. Sarcopenia doesn't discriminate when it comes to muscle -- it's the great equalizer on your body's slow march to the grave. Everything from blinking to breathing to going a whole day without crapping your pants is controlled by those useful little bundles of protein filament. In other words, better start Kegeling your heart out now, because pretty soon the dam will be ready to burst, and you're going to need all the sphincter strength you can muster.

Emma Larkins stays young by living in a magical make-believe world where people can fly. Check out her first science-fiction novel, Mechalarum, and follow her on Twitter as she attempts to keep a small segment of society moderately entertained.

For more from Emma on Cracked, check out 5 Movie Romances That Won't Last (According to Science) and 6 Reasons NYC Is the Most Overrated Vacation Destination.

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