If you smoke, you already know you need to quit. It's bad for your heart, lungs, brain, and even your sex life.

But let's face it: You'd have kicked the habit yesterday if smoking's ill effects were a bit more obvious. What if each cigarette created a black pockmark（麻子） on your face, for instance?

Well, smoking does damage your looks. Read on to discover 15 ways smoking is ruining your appearance.

Bags under your eyes
Don't you hate it when you can't get a good night's sleep-and it shows on your face?

If you smoke, you're four times as likely as nonsmokers to report feeling unrested after a night's sleep, according to Johns Hopkins study.

Why the lack of shut-eye? It's possible that nightly nicotine withdrawal could be causing you to toss and turn（辗转反侧）. And unfortunately, poor sleep doesn't equal pretty.

Psoriasis
To be fair, psoriasis is an autoimmune-related skin condition that can show up even if you never touch a cigarette.

However, if you do smoke, your risk for the scaly skin condition goes up-a lot.

According to a 2007 study, if you puff a pack a day for 10 years or less, psoriasis risk goes up 20 percent; 11–20 years and your risk is 60 percent higher; and for those who pass the two-decade mark, the psoriasis risk more than doubles. (Even secondhand smoke during pregnancy or childhood is linked to a higher risk.)

Icky teeth
Wouldn't you love to have a set of dazzling white, Hollywood-like choppers? If you smoke, you can kiss that dream good-bye.

It's the nicotine in cigarettes that can stain teeth.

So in addition to the escalating costs of buying and smoking your cigs, add in the cost of tooth whitening. A professional procedure to clean your teeth costs an average of $500 to $1,000.

Premature aging and wrinkles
We can all appreciate a wizened visage-on our favorite nonagenarian that is. Wrinkles look anything but wise when they show up on a relatively young person who smokes.

And show up they will. Experts agree that smoking accelerates aging, so that smokers look 1.4 years older than nonsmokers, on average.

Why the wrinkly face? Smoking hampers the blood supply that keeps skin tissue looking supple and healthy.

Yellow fingers
The nicotine in cigarette smoke can not only make your teeth (and the walls of your home) brown, but it's also notorious for staining fingers and nails as well.

If you search the Internet, you can find a number of home remedies, including lemon juice, bleach solutions, and scrubbing with steel wool. Ouch.

Wouldn't it be easier-and less painful-to just quit?

Thinner hair
As if the wrinkly skin wasn't enough, smoking hurts your hair too. Experts think the toxic chemicals in smoke can damage the DNA in hair follicles and generate cell-damaging free radicals as well.

The end result? Smokers have thinner hair that tends to go gray sooner than nonsmokers. That is, if they have any hair at all.

Men who smoke are about twice as likely to lose their hair as nonsmokers, after taking into account factors that increase the risk of baldness, such as aging and genetics, according to a 2007 study in Taiwan.

Scarring
Nicotine causes vasoconstriction, a narrowing of the blood vessels that can limit oxygen-rich blood flow to the tiny vessels in the face or other parts of the body.

This means your wounds will take longer to heal and you'll have scars that are bigger and redder than you would in a nonsmoking parallel universe.