Cancer Trends Progress Report

The prevalence of adult cigarette smoking in the U.S. has steadily declined since the first Surgeon General’s Report on the harms of smoking was published in 1964, when smoking prevalence was 42 percent. While the prevalence of daily smoking has dropped over time, nondaily smoking has remained relatively stable. Many studies show that there is no safe level of smoking. For example, individuals who smoke even a few cigarettes per month over their lifetime are at a higher risk of smoking-related death than never smokers, according to the Dose-Response Association of Low-Intensity and Nondaily Smoking With Mortality in the United States article, published in the journal JAMA Network Open.

Besides cigarettes, other tobacco products are also used by U.S. adults. In 2019, the NHIS reported that 8.7 million adults (3.7%) smoked cigars, 5.9 million adults (2.5%) used smokeless tobacco and 10.9 million (4.8%) used e-cigarettes.

A cigar is defined as a roll of tobacco wrapped in leaf tobacco or in a substance that contains tobacco (whereas a cigarette is defined as a roll of tobacco wrapped most often in paper or some other non-tobacco substance). There are three major types of cigars currently sold in the U.S. – large cigars, cigarillos, and little cigars. Little cigars are about the same size as a cigarette and often include a filter. Cigar smoking in the U.S. has recently been characterized by increasing product diversity, and marketing of these products has been targeted to specific population groups, including urban African Americans, which has contributed to an increase in prevalence of their use among adolescents and young adults.

Like cigarette smoke, cigar smoke contains toxic and carcinogenic compounds that are harmful to both smokers and nonsmokers. Cigar smoking causes oral cavity cancers (cancers of the lip, tongue, mouth, and throat) and cancers of the larynx (voice box), esophagus, and lung. Gum disease and tooth loss are also linked to cigar smoking, and heavy cigar smokers and those who inhale deeply may further be at increased risk of developing coronary heart disease. Heavy cigar smoking also increases the risk for lung diseases, such as emphysema and chronic bronchitis, which can be risk factors for lung cancer.

Smokeless tobacco is also known as chewing tobacco, spit tobacco, snuff, dip, or snus. Snuff is a finely cut or powdered tobacco that is either placed between the cheek and gum, or sniffed through the nose, respectively. Some moist snuff and all snus come in tea bag-like pouches. Chewing tobacco is used by putting a wad (loose leaves, plug, or twist) of tobacco inside the cheek.

Chewing tobacco and snuff contain at least 28 cancer-causing agents. Use of smokeless tobacco causes oral, esophageal, and pancreatic cancer. Smokeless tobacco also causes serious oral health problems, including gum disease, other non-cancerous oral lesions, and tooth loss, and increases the risk of heart disease.

E-cigarettes (also known as vapes or Electronic Nicotine Delivery Systems) are battery-powered devices that convert a liquid (“e-liquid”) into an aerosol. E-liquids typically contain nicotine, flavorings, vegetable glycerin, propylene glycol and other chemicals. Besides nicotine, e-cigarette aerosol may contain heavy metals, volatile organic compounds, and fine and ultrafine particles that can be inhaled deeply into the lungs by both users and by-standers. 

E-cigarette use among adults may potentially reduce the health risks associated with conventional cigarette smoking if users switch completely to e-cigarettes. However, a large percentage of U.S. adults who use e-cigarettes also smoke conventional cigarettes and are at continued risk for exposure to their toxic and carcinogenic compounds, and subsequent smoking-related morbidity and mortality. More concerningly, almost a quarter of those who use e-cigarettes report never having smoked, and the majority of this group is 18-24 years old. As noted above, overall, 4.8 percent of U.S. adults (10.9 million people) were current e-cigarette users in 2019. E-cigarette use was higher among men than women (5.7% vs. 3.8%), among young adults (aged 18-24) than adults overall (9.2% vs. 4.1%), and among those who identify as lesbian, gay, or bisexual vs. heterosexual/straight (11.5% vs. 4.2%).

In 2019, the U.S. experienced an outbreak of e-cigarette and vaping associated lung injury (EVALI). As of February 18, 2020, a total of 2,807 EVALI cases or deaths were reported to the Centers for Disease Control and Prevention (CDC). The U.S. Food and Drug Administration (FDA), CDC, and state health authorities have determined that tetrahydrocannabinol (THC)-containing e-cigarette, or vaping, products are linked to most EVALI cases. Vitamin E acetate is strongly linked to the EVALI outbreak; however, evidence is not sufficient to rule out the contribution on other chemicals of concern.

Cigarette smoking is the leading preventable cause of disease, disability, and death in the United States. Smoking causes cancers of the lung, esophagus, larynx, mouth, throat, kidney, bladder, liver, pancreas, stomach, cervix, colon and rectum, anus, as well as acute myeloid leukemia. Altogether it causes approximately 30 percent of all U.S. cancer deaths each year. The American Cancer Society estimates that in 2021, almost 182,571 of the estimated 608,570 cancer-related deaths will be caused by cigarette smoking.

Presently, the COVID-19 pandemic poses a major threat to public health in the U.S. and across the world. Current and former cigarette smoking can increase an individual’s risk of severe illness from COVID-19. To reduce the chance of severe illness, current smokers should quit, and former and never smokers should refrain from using cigarettes.