How does your body digest a cigarette?

What else happens when you smoke?

Smoking causes wrinkles around the eyes, called crow's feet.
Smoking causes wrinkles around the eyes, called crow's feet.
Hans Neleman/Getty Images

Another thing that happens when you smoke is that your blood pressure rises by about 10 to 15 percent. High blood pressure means you have an increased risk of heart attack and stroke. Smoking not only affects the pressure, but it also damages the blood itself. As we mentioned before, when you smoke, carbon monoxide (CO) is created and ingested -- so much that smokers have about 4 to 15 times the amount of CO in the body than non-smokers. Carbon monoxide also is the same stuff that comes out of your car's tailpipe. When you smoke, it stays in your bloodstream for about six hours. This harmful chemical compound does its best to rob every cell in your body of oxygen, something cells need to function. 

Most smokers know the damage they're causing to their lungs, heart, blood vessels, and senses of taste and smell. Something many smokers may overlook is the damage being done to their skin. While many of smoking's negative effects are reversible once you quit, there's no way to undo the skin damage. The blood vessels in the skin constrict when you light up, limiting the amount of oxygen the skin gets. The intrusion of CO puts further limits on the oxygen the skin needs. What does this mean? Wrinkles. "Smoker's face" is a condition long-term smokers suffer from. What does it look like? Deep, dark lines around the eyes and the corners of the mouth, for starters. The skin may also appear gray in color, and facial features may appear gaunt. Not a pretty sight. One study shows that nearly half of all smokers get smoker's face.

So besides wreaking havoc on your insides, cigarettes also ages you prematurely. If this isn't enough to inspire you to put down the pack, think about your sex life. Research conducted by Boston University's medical school has shown that when men smoke, it can lead to erection problems. Among the 1,011 men studied that had erectile dysfunction, 78 percent were smokers. The study found that the amount of blood flowing to the penis was directly proportional to the number of cigarettes smoked. Smoking also lowers sperm count and can even alter the shape of the little guys. So if you're looking to have kids, you may want to think about quitting. Women don't get a free pass in this department either. Ladies who smoke heavily show a 43 percent decline in fertility and reach menopause nearly two years earlier, decreasing their reproductive years.

So how does the body digest a cigarette? It really doesn't. There's the exhale, but that's simply because the body can't completely absorb every bit of smoke from the inhale. The harmful chemicals in cigarettes tear through every cell of your body like looters in a riot. The smoke affects the blood, skin, lungs, heart, your senses of taste and smell, and anything else it comes into contact with. Kicking the habit is a tough task, but it's one that's well worth the effort. You may not be able to reverse the effects of premature wrinkling, but you can help out the rest of your body. As soon as you stop, your body goes into fix-it mode. Your cilia wake up and start sweeping again, and your taste buds fight through the tar. Oxygen is again delivered in full supply to your heart and the rest of your body. The days turn into weeks and months and eventually years and before you know it, you may feel like you never lit up in the first place.

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More Great Links


  • "All about smoking." 2008.
  • "Clearing the Air on the Hard Facts of What Smoking Does to Your Body." 2008.
  • "Harmful Effects of Smoking." 2008.
  • "Smoking Cessation." American Heart Association. 2008.
  • "Smoking: Does it cause wrinkles?" Mayo Clinic. 2008.
  • "Tar Information Sheet." 2008.
  • "What happens when you smoke?" 2008.
  • "What's in a cigarette?" Signal One Smokebusters. 2008.