Can You Smoke the Pounds Away?

Like wearing black, smoking seems to be a requirement for entry into the glam world of high fashion. And supermodels like ultra-thin icon Kate Moss routinely are photographed with a smoldering cigarette dangling from their well-manicured fingertips.

These images create the impression that smoking and thinness go hand in hand. It’s a connection that appears to resonate with body-conscious young women. But what does science say about this suggestive relationship? Does smoking promote weight loss?

The short answer: No.

An important study by McGill University researchers tracked the weight and smoking status of 1,300 12- and 13-year-old girls for five years and found no difference in weight gain between the smokers and non-smokers. Yet, like so many weight-loss fads, the idea that smoking has a slimming effect persists. According to a study of 12- to 15-year-old female smokers published in the British Medical Journal, teens who attach the most importance to being thin are four times as likely to become established smokers later in life.

The story of smoking and weight loss is a complicated one. This, no doubt, contributes to the speculation that smoking is an effective way to stay slim. There is evidence, for example, to suggest a smoking habit will boost resting metabolism, thereby helping smokers burn more calories.

What’s more, population studies show smokers tend to weigh less than nonsmokers. However, these trends don't hold true for very heavy smokers.

For example, University of Kansas researchers found in a 2006 study that heavy smokers tend to exercise less, eat in front of the television more often and frequent restaurants that serve high-calorie food much more often than nonsmokers, suggesting heavy smoking often occurs alongside a package of unhealthy behaviors that can lead to obesity.

All of this evidence—while at times conflicting—points to the same message: Those concerned with body image should never start smoking in the first place. Smoking has devastating effects on the lungs and is a risk factor for dozens of diseases, including cancer. The vast majority of research suggests smoking does not promote weight loss and, if anything, smokers who later try to quit actually are prone to weight gain.

This is where the “link” between smoking and thinness is strongest in perception if not reality. In fact, the federal Centers for Disease Control and Prevention estimates that 80 percent of smokers gain weight when they give up cigarettes—usually between 5 and 15 pounds. For smokers, this prospect looms large and can become the primary obstacle to quitting.

So, why do smokers fatten up when they give up nicotine? Several factors likely are at play. The body’s metabolism adjusts to nicotine withdrawal by slowing down and burning fewer calories. If former smokers fail to temper their eating habits, the pounds pack on quickly.

Moreover, several studies have shown that smoking dulls your sense of taste. For long-term smokers who give up the habit, food may suddenly seem more delicious and appealing, leading to over-consumption and a bulging waistline. Some research points to smokers feeling fuller faster than non-smokers. So ex-smokers are likely to feel ravenous and need to adjust their appetites and eating habits.  

“One of the physiologic effects that probably occurs with smoking is increased satiety when you do eat,” say Dr. J. Taylor Hays, associate medical director at the Mayo Clinic Nicotine Dependence Center in Rochester, Minn. “They can be much more controlled eaters and have longer intervals between eating.”

Plus, the average smoker spends more than an hour each day puffing on cigarettes. Quitting often causes smokers to seek out a substitute behavior such as snacking more frequently and, probably, absentmindedly.

But weight gain isn’t inevitable. Some studies suggest quitters who consume an extreme low-calorie diet can stave off the extra pounds, while experts at the Mayo Clinic advise smokers concerned about the issue to try slimming down before quitting tobacco. Others recommend nicotine replacement therapy, such as a nicotine patch, which appears to lessen the amount of weight gained by smokers during the cessation process.

Dieting and exercising during withdrawal also may work, but this last bit of advice is probably easier said than done. Giving up smoking is stressful enough without the added strain of trying to lose weight. That’s why some experts recommend a different approach—don’t worry about the weight gain until you’ve vanquished your cigarette habit.

Korey Capozza is a San Francisco-based writer who contributes frequently to MSN Health & Fitness.