Tobacco use is the single largest preventable cause of cancer and premature death worldwide. An estimated 1.3 billion people in the world currently smoke tobacco; the vast majority of these smoke manufactured cigarettes (
4). If current trends in smoking and population growth continue, the number of current smokers is expected to reach 2 billion worldwide by 2030 (
5). As shown in , smoking prevalence is highest among men in Eastern Europe, the former Soviet Union, China and Indonesia. Cigarette smoking among women has been decreasing in most high-resource countries but is stable or increasing in several countries in Southern, Central and Eastern Europe (
4). With the decline of tobacco use in many industrialized countries, the geography of smoking has shifted from the developed to the developing world, especially for men. About 50% of men and 9% of women are current smokers in developing countries, compared with 35% of men and 22% of women in high-resource countries (
4). Over 60% of all smokers in the world live in just 10 countries (in order): China, India, Indonesia, Russian Federation, USA, Japan, Brazil, Bangladesh, Germany and Turkey (
6). The number of current smokers in China approximately equals the entire population of the USA. While most of these smokers are currently under age 40, the combination of continued smoking and aging will vastly increase the future adverse effects of tobacco use on cancer and other chronic diseases, unless effective campaigns can be mounted to promote cessation.
The International Agency for Research on Cancer designates at least 15 different types or subtypes of cancer as causally related to smoking (
7). These include cancers of the lung and bronchus (all histological subtypes), larynx, oral cavity, pharynx, lip, nasopharynx, nasal cavity and paranasal sinuses, esophagus (squamous and adenocarcinoma), bladder, kidney (parenchyma and renal pelvis), pancreas, uterine cervix, stomach, liver and acute myeloid leukemia (
7). Cancers attributed to cigarette smoking accounted for more than one-fifth of the estimated 1.42 million cancer deaths that occurred globally in the year 2000 (
8). Lung cancer is the most common cancer caused by smoking, even though it accounts for less than half of all smoking-attributable deaths (
9). Cigarette smoking accounts for ~80% of lung cancer cases in men and 50% in women worldwide (
5). Lung cancer has been the most common cancer in the world since 1985 (
10).
In many countries, temporal trends in smoking, and more recently in smoking cessation, have been so extreme that they have dominated national trends in cancer mortality (
9). For example, the downturn in death rates from smoking-related cancers in men, ages 65–69 that began in the UK in the early 1960s, in the USA in the mid-1980s and in Poland in the early 1990s, has been the major driver in the downturn in death rates from all cancers combined in these countries (
9). This has occurred despite the delay that occurs between reductions in smoking prevalence and reductions in lung cancer mortality, seen when comparing and for men in North America and Western Europe. Progress in reducing male lung cancer rates was achieved principally by smoking cessation among adult men. Unfortunately, cessation rates are much lower in large developing countries like China than in the West. In China, many millions of young cigarette smokers who began smoking in adolescence are now aging. The future risks of cancer or other diseases caused by smoking may eventually be greater among these younger generations of Chinese men who began smoking in childhood than those now seen among Chinese smokers who initiated smoking later in life (
9).
Despite this bleak picture, much progress can and is being made to reduce tobacco smoking, especially in high-resource countries. In the USA, per capita cigarette consumption has decreased to levels not seen since the start of World War II. Projections based on data from the Food and Agriculture Organization of the United Nations indicate that tobacco consumption will continue to fall in economically developed countries but will rise in most low- and medium-resource countries (
11). A number of interventions have proven to be effective in reducing the demand for tobacco products and in changing social norms about smoking. Tax policies that raise the price of tobacco products are the single most effective approach for reducing demand. Price increases are an especially powerful deterrent against the initiation of smoking in youth (
12,
13,
14) and motivation for addicted smokers to quit. Although the impact of price on cigarette demand varies widely depending on the population studied and study design, a 10% increase in cigarette prices result in a 2.5–5% reduction in cigarette demand in high-resource countries. Estimates of price responsiveness in low- and middle-income countries are at least as large (
15).
Smoke-free laws that prohibit smoking in public places substantially reduce non-smokers’ exposures to secondhand smoke, change social norms about smoking and motivate smokers to quit. Successful smoke-free interventions by Ireland and other countries have greatly broadened the protection of non-smokers. Public awareness about the harmful effects of tobacco on health can be increased by requiring prominent, graphical warnings on cigarette packaging (
16) and by educational campaigns aimed at health professionals. These are especially important in low- and medium-resource countries, where baseline levels of awareness about the extent of tobacco's deleterious effects are low and doctors still smoke. In China, 61.3% of male physicians smoke, compared with 66.9% of the general male population.
Many of the adverse health effects of smoking can be averted by cessation. Smoking cessation is the only effective way to reduce risk for the 1.3 billion smokers in the world. As mentioned above, widespread smoking cessation among men in high-income countries since the 1950s is largely responsible for the significant decrease in death rates from lung and other smoking-related cancers in these countries. Although pharmacological treatment is less affordable in economically developing than in high-resource countries, brief counseling interventions by health care personnel are feasible. Counseling about smoking cessation can be integrated into other public health and health care delivery programs, such as tuberculosis, human immunodeficiency virus (HIV)/AIDS, family planning and maternal health programs.
No single country can successfully combat the resources of the international tobacco companies. Thus, nations have united behind the Framework Convention on Tobacco Control (FCTC), the first health treaty negotiated under the auspices of the World Health Organization (WHO). The FCTC provides a framework for national legislation and enforcement of tobacco control measures. The FCTC was promulgated in May 2003 in response to the global tobacco pandemic with the objective of substantially reducing the worldwide prevalence of tobacco use and exposure to tobacco smoke. As of August 2009, 166 countries have ratified the treaty, representing ~80% of the world's population. FCTC provisions establish international standards for tobacco taxation, advertising and sponsorship, regulation, trade, etc. Effective measures against smuggling are especially important. Estimates suggest that 6–8% of cigarettes consumed globally are contraband products, shipped to avoid taxes. Smuggling can be deterred by prominent tax stamps that cannot be counterfeited easily, local language warnings on cigarette packs and aggressive enforcement of anti-smuggling measures and penalties.
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