Federal taxes on cigarettes went up months ago and now President Obama has signed legislation letting the FDA regulate tobacco. You'd think that smoking rates would fall. But there's a hitch: When times are tough, smokers tend to smoke more and put off their quit dates.
 
We spoke to NBC News Medical Editor Nancy Snyderman, MD, to learn how to fight the urge to light up.

Q: Why do people smoke more when times are tough?

Dr. Nancy Snyderman: When money is short, you'd think that people would stop wasting money on cigarettes. But under stress people smoke more. They eat more high-fat foods too. Part of it is the "What the heck?" phenomenon when you're under stress.

I've always felt impatient with people who constantly struggle to quit smoking and repeatedly fail. But now genetic research on this phenomenon is awakening new sympathies in me. As a medical journalist I recently attended the annual meeting of the Society of Behavioral Medicine where I learned that not all nicotine dependence is equal. While kicking the habit may be an uphill struggle for some people, it's more like climbing Mount Everest for others.

Research by Caryn Lerman, Ph.D. and colleagues, from the Transdisciplinary Tobacco Use Research Center at the University of Pennsylvania, has shown that - willpower and inner strength aside - part of your battle to butt out has already been lost or won at the genetic level. Dr. Lerman's group has found that genes determine how quickly or slowly smokers metabolize nicotine, and thus how quickly they are driven to light their next cigarette. Genes also determine just how good smoking makes you feel, and on the flipside, how painful it is to quit. We know that nicotine is a feel-good drug which stimulates the release of opiates in the brain. That's why quitting is so hard. But for smokers with a particular genetic make-up, quitting actually reduces activity in a part of their brain - the dorsolateral prefontal cortex - which impairs their cognitive function, says Dr. Lerman. "This brain connection may explain why they are at such high risk for relapse," she said, adding that, for these smokers, simply lighting up again reverses their brain fog.