Why is it so hard to quit smoking?

Humans have been ingesting nicotine for thousands of years. It preceded Camel Joe's first gallop and was used well before she came a long way, baby. Nicotine was born in the Americas, and once the United States was colonized, it was cultivated and exported to Europe and around the world. As early as the 1600s, doctors suspected that smoking was dangerous to your health. It took quite a bit longer for these suspicions to be verified and even longer before the United States government took action with warning labels. Smokers that figured out on their own that it was dangerous were faced with irritability, sleep disturbances, increased appetite, major cravings and attention deficit.

Nicotine tricks your brain by stimulating the reward pathways with a shot of dopamine, the hormone that tells us that things like food and sex are pleasurable. It also increases activity in the cholinergic pathways of the brain. These pathways are concentrated in the brain stem and are believed to be involved in cognitive functions, like memory. An increase here makes you feel sharper and more focused. As if that's not enough, nicotine also increases your endorphin levels, the proteins that give you feelings of euphoria. At night when you aren't smoking, those pathways are shut down again and you wake craving cigarettes. One-third of all smokers have their first cigarette of the day within 10 minutes of waking up [source: FDA].

Naturally occurring nicotine levels found in tobacco already make smokers want to smoke. Then the Marlboro Man came along and tipped the scales more by souping-up the nicotine with the addition of sugar. When sugar is burned, it produces a chemical called acetaldehyde. Research studies on lab rats have shown that the little rodents will repeatedly self-administer shots of acetaldehyde much like they would nicotine.

Cigarette maker Phillip Morris conducted internal studies that showed that acetaldehyde and nicotine make for pretty good bedfellows. On average, lab rats self-administered 240 doses of acetaldehyde per day, compared to 90 doses of nicotine. When the two chemicals were combined and the rats could choose to administer the cocktail over the individual ingredients, they did so in spades -- with a whopping 400 doses per day [source: Ralof]. Nicotine replacement therapies like gum and patches may help to stave of the desire for nicotine, but they don't touch the acetaldehyde. Another interesting factoid -- when the body begins to break down alcohol, it produces acetaldehyde. So if you have a harder time not reaching for a smoke when you have a beer in your hand, it's no coincidence. Once the acetaldehyde is active in your system with that drink, you'll crave more in the form of a cigarette.

Another thing that makes it tough to stop smoking is something called free-base nicotine. This is a variation of the molecular structure of nicotine in which a hydrogen ion is missing. Why is that hydrogen ion special? Without it, nicotine vaporizes more easily into a gas, putting it on the express train to your lungs and from there, a quick ride to the brain. Any drug delivered to the brain more quickly is more addictive. Free-base nicotine basically does for smokers what crack does to cocaine users.

Here's where it gets interesting. Some brands of commercial cigarettes have been found to contain 10 to 20 times the amount of free-base nicotine than previously believed [source: Medical News Today]. Not only that, but the free-base nicotine is also packed more heavily toward the front of the cigarette, so those first few puffs really pack a wallop. Is it by some miracle that nicotine transforms into the free-base variety? Hardly. It's helped along by the addition of ammonia to your smoky treat.

Besides the fact that cigarette manufacturers have done everything in their power to make it as hard as possible to quit smoking, there are some other factors that go into it as well.

We've touched on a few ways cigarette companies have gotten you hooked and aimed to stay hooked. Unfortunately, there are even more factors that make it difficult to kick the habit. One could be your gender.

A 2004 study by the University of Ohio found that hypnosis is more helpful to men than women who are trying to quit smoking. Over the course of 18 studies involving 5,600 participants, the research shows men hold a 7 percent edge over the ladies. That may not sound like much, but when cessation success rates are in the 20 to 30 percent range to begin with, it's a pretty big advantage. This doesn't mean that women are less susceptible to hypnosis -- it may have more to do with overall success rates for women. Research has shown that, if anything, women are more able to be hypnotized. They just have a harder time quitting smoking than men. One reason is that nicotine replacement therapy, like the patch, isn't as effective for women. Another theory is that women may be more concerned about weight gain associated with kicking butts.

Your genetic makeup may also play a part, so you can thank mom and dad. Research from the University of Michigan released in August 2008 indicates that if you have the nicotine receptor gene CHRNA5, you're more likely to enjoy that very first cigarette. Out of 435 smokers and nonsmokers who had tried cigarettes in their life, the ones who kept smoking reported that their first cigarette gave them a pleasurable experience. These same participants were also more likely to have the variant of the CHRNA5 gene. This means that for some people, the first smoke they ever have will make them want to come back for more. How's that for not having a fighting chance?

Another study by the Indiana University School of Medicine shows that some forms of mental illness go hand-in-hand with nicotine addiction. Like peanut butter and jelly, bipolar disorder and cigarettes make a likely pair. Depending on where you're from, the average population of smokers is about 20 to 25 percent -- people with some form of mental illness clock in at about 50 percent. Seventy-five to 90 percent of people who suffer from schizophrenia are smokers. Alcoholics aren't far behind at an average of 80 percent. Bipolar disorder comes in at 60 to 70 percent [source: Rudavsky].

Eight out of every 10 smokers say they wish they'd never started, yet only one in 10 can successfully quit. The good news is that quitting can and does happen all the time to all kinds of people. Some do it by going cold turkey. Some need the help of nicotine replacement therapy (Sharecare.com). Hypnosis works for some folks, and others need more intense prescription medication to help them kick the habit. Two million people quit smoking every year, and there's no reason you can't be one of them. No matter how many years you've smoked, your body will immediately begin to repair itself once you've put out your last butt. It's intimidating, so you might try by cutting back to begin with. A review of smoking studies in people that had no desire to quit showed that cutting down often led to complete cessation [source: Science Daily] .

For more information on smoking and health, please explore the links on the next page.