Although fewer US adults are smoking these days, millions are still lighting up and suffering the consequences, according to two recent reports from the Centers for Disease Control and Prevention. Both reports appear in the CDC's Morbidity and Mortality Weekly Report ( Vol. 52, No. 35: 842-844 and Vol. 52, No. 40: 953-956).

The CDC reports that more than 46 million American adults – about 23% of the population – were current smokers in 2001. That figure is about 2% lower than the number of people who reported smoking in 1993.

While any decline in the smoking rate is good news to public health officials, the report isn't all rosy: The decline is not fast enough to meet the national health goal of cutting adult smoking to 12% by 2010.

"For smoking, it's incredibly important to meet the 2010 goals because smoking is the leading cause of (preventable) death in this country, and if we can reduce smoking prevalence we can save a lot of lives," said Corinne Husten, MD, a medical officer with the CDC's Office on Smoking and Health.

Reducing the smoking rate would also cut the staggering number of Americans living with debilitating diseases caused by tobacco. Researchers from the CDC, the Roswell Park Cancer Institute in Buffalo, New York, and the Research Triangle Institute in North Carolina have come up with the first such estimate, detailed in another CDC report.

Using data from national health surveys, the researchers calculated that 8.6 million people in the United States have a serious illness caused by smoking.

"That's a little bit more than the entire population of New York City," said co-author Andrew Hyland, PhD, of Roswell Park's Division of Cancer Prevention and Population Science.

Most of those people -– about 59% -- have either chronic bronchitis or emphysema, lung conditions that make breathing difficult and can be deadly. Smoking-related cancers accounted for 13% of the serious diseases; more than 1.5 million people are affected.

Among cancer cases, lung cancer accounted for only 1% of cases (184,000 people). Yet lung cancer strikes nearly 172,000 Americans each year, and kills more people than any other cancer. Why weren't the numbers in the survey higher?

Hyland has one explanation. "The reality is, if you have lung cancer, the survival is just a few months."

Lung cancer is frequently not found until it is advanced, when it kills quickly. Many patients simply don't survive long enough to be found by surveys like the ones used to collect this data.

This is the first time researchers have tried to quantify the chronic health effects of smoking, as opposed to looking at the number of deaths it causes. But as shocking as the figure is -- 8.6 million Americans with serious illnesses -- Hyland says it probably understates the problem.

"Our estimates, I think, are very conservative," he said.

The surveys only looked at a handful of serious smoking-related illnesses, he explained, and did not include less debilitating conditions, like sinusitis, impotence or impaired wound healing. Also, only diseases related to smoking were included; if the researchers had also included diseases related to other tobacco products, like chewing tobacco or snuff, the numbers would have been higher, Hyland said.

Husten pointed out that smokers with serious, chronic illnesses can benefit from quitting.

"The good news for people living with these diseases is, if they quit they can slow the progression of the disease and perhaps prevent some of the complications," she said. "Quitting is very important to maximize length and quality of life."

According to reports from the US Surgeon General's office, some health benefits of quitting, like lower blood pressure, start to kick in within hours of the last drag on a cigarette. Within a few months, lung function improves.

Even for long-time smokers the risk of heart attack drops markedly after about a year, and by 15 years they have the same risk as non-smokers. Ten years after quitting the risk of lung cancer is half that of a current smoker. The risk of other cancers (mouth, bladder, and others) also is lower.

If the benefits of quitting are so great, why do so many Americans still smoke?

"There's no easy answer," said Hyland. "Nicotine dependence is a terrible addiction."

There are tools to help smokers fight this deadly addiction, and smokers who are serious about quitting should take advantage of them, Husten said. "Part of the reason the success rates (for quitting) are so low is that most people try to do it on their own."

In fact, only 15% of current smokers and 6.8% of former smokers report using any of the recommended therapies in their last quit attempt.

First and foremost, smokers should enlist the help of their doctor, Husten said. Physicians can help smokers find appropriate medications for controlling nicotine cravings -- and steer them away from remedies that haven't been proven to work. Doctors can also give practical advice about what to expect when trying to quit, and help smokers develop a plan for weathering rough patches.

Another valuable resource is telephone quitlines, which are available in many states. These services offer free advice and counseling to smokers trying to quit, and can provide important support that a busy doctor may not be able to give.

"The best strategy is to be on the medication and be getting some form of intensive counseling," said Husten. Of course, medication may not be appropriate for some smokers (pregnant women, adolescents, people with contraindications) so it's important to consult a doctor before taking any drugs, she added.

Enlisting the help of family and friends is also important, Husten said. Smokers can ask their friends and relatives not to smoke around them, or offer them cigarettes, and to have a little extra patience if grumpiness sets in.

"The really key point is for people to get help to quit smoking," Husten said. "People don't hesitate to get help for other medical problems, and they shouldn't hesitate to get help for this one."

Persistence also pays off, she said. "If they've tried to quit in the past and weren't successful, that doesn't mean they won't be successful this time. They need to keep trying."