Throat cancer has several well-established causes, with tobacco use, alcohol consumption, and human papillomavirus (HPV) infection responsible for the vast majority of cases. The specific cause often depends on where in the throat the cancer develops, whether in the voice box (larynx), the back of the throat (pharynx), or the area behind the nose (nasopharynx). Understanding these causes can help you assess your own risk and take practical steps to lower it.
Tobacco and Alcohol: The Leading Combination
Tobacco use remains the single largest driver of throat cancer worldwide. Smoking cigarettes, cigars, or pipes exposes the lining of the throat to dozens of cancer-causing chemicals with every inhale. Chewing tobacco and snuff carry similar risks because the carcinogens sit directly against the tissues of the mouth and throat. The longer and more heavily you use tobacco, the higher the risk climbs.
Alcohol is a strong risk factor on its own, but what makes the combination of tobacco and alcohol particularly dangerous is the way they amplify each other. A large pooled analysis published in Cancer Epidemiology, Biomarkers & Prevention found that using both tobacco and alcohol together more than doubled the expected cancer risk beyond what either substance would cause alone. For cancers of the oral cavity specifically, the multiplying effect was even higher, roughly tripling the additional risk. Alcohol is thought to act partly as a solvent, making it easier for tobacco’s carcinogens to penetrate the cells lining the throat.
HPV: The Fastest-Growing Cause
HPV has reshaped the profile of who gets throat cancer. About 70 percent of newly diagnosed oropharyngeal cancers in the United States are now HPV-positive, according to the National Institute of Dental and Craniofacial Research. This type of throat cancer is most common among non-smoking younger adults, a group that historically had very low rates.
HPV type 16 is the strain responsible for most of these cases. The virus produces two proteins that essentially disable the body’s built-in cancer defenses. One protein breaks down p53, a molecule that normally detects DNA damage and triggers cell death before a damaged cell can multiply. The other disables a second checkpoint protein that controls when cells are allowed to divide. With both brakes removed, infected throat cells can accumulate mutations and grow unchecked. The virus also appears to stabilize the protective caps on chromosomes (telomeres), letting infected cells divide indefinitely rather than aging and dying off as healthy cells would.
HPV is transmitted through oral sexual contact. The infection is extremely common, and in most people the immune system clears it without any problems. Only a small fraction of persistent infections eventually lead to cancer, typically over a period of years or decades.
HPV Vaccination
The FDA has approved the 9-valent HPV vaccine (Gardasil 9) for prevention of oropharyngeal and other head and neck cancers caused by several high-risk HPV types, including type 16. This approval was granted under an accelerated pathway based on the vaccine’s proven ability to prevent HPV infections in other parts of the body, with a confirmatory study currently underway for throat-specific protection. Vaccination is most effective when given before any exposure to the virus, which is why it’s recommended for preteens and young adults.
Epstein-Barr Virus and Nasopharyngeal Cancer
A different virus drives cancer in the nasopharynx, the area where the back of the nose meets the throat. The Epstein-Barr virus (EBV), best known for causing mono, is found in more than 95 percent of undifferentiated nasopharyngeal cancers regardless of where in the world they occur. The virus persists in a dormant state inside throat cells, producing a protein called LMP1 that functions as a powerful growth signal. LMP1 activates multiple pathways that block cell death, promote cell division, and may help cancer cells spread. Other viral proteins help infected cells evade the immune system.
Nasopharyngeal cancer is most common in southern China, Southeast Asia, and parts of North Africa, suggesting that genetic susceptibility and regional environmental or dietary factors interact with EBV to trigger the disease. Most people carry EBV (it infects roughly 90 percent of adults worldwide), so the virus alone is not sufficient to cause cancer.
Workplace Exposures
Certain occupational hazards carry a measurable risk, particularly for laryngeal cancer. Asbestos and strong inorganic acid mists are confirmed carcinogens for the larynx, according to the International Agency for Research on Cancer. Workers in industries that involve cement, polycyclic aromatic hydrocarbons (from combustion and petroleum processing), and wood dust also face probable increased risk.
The picture differs somewhat for pharyngeal cancers. Coal dust exposure has been linked to a more than twofold increased risk of cancer in the lower part of the throat (hypopharynx), though the same link hasn’t been established for the larynx. Other suspected carcinogens include formaldehyde, organic solvents, leather dust, silica dust, and cotton dust. Workers exposed to these substances over long periods, especially without adequate respiratory protection, accumulate the highest risk.
Chronic Acid Reflux
Gastroesophageal reflux disease (GERD) exposes the larynx and lower throat to repeated acid contact, and that chronic irritation appears to promote cancer. Researchers at the National Cancer Institute, using data from the large NIH-AARP Diet and Health Study, found that acid reflux disease was associated with a twofold increased risk of laryngeal squamous cell carcinoma. This connection is separate from tobacco and alcohol use, meaning GERD adds risk even in people who don’t smoke or drink heavily. Managing reflux effectively, whether through dietary changes, weight management, or medication, reduces the ongoing damage to throat tissue.
Poor Oral Health
The state of your mouth matters more than you might expect. Periodontal (gum) disease is strongly associated with increased risk of head and neck cancers. The connection works through several pathways: chronic gum inflammation generates a steady stream of inflammatory signals known to promote cancer development, while the overgrowth of certain harmful bacteria produces compounds that can directly damage DNA. Two bacterial species in particular, Porphyromonas gingivalis and Treponema denticola, have been linked to oral squamous cell carcinoma and can interact with oral fungi to worsen disease progression.
The mouth hosts up to 1,000 microbial species, and when this community falls out of balance, it can affect inflammation, immune responses, and gene expression in surrounding tissues. Research from USC’s Ostrow School of Dentistry indicates that improving oral hygiene reduces overall cancer risk and improves survival in people who already have oral cancer.
Diet and Nutritional Gaps
A diet low in fruits and vegetables is consistently linked to higher throat cancer risk. Researchers at Maastricht University found that higher intake of vitamin C from food sources significantly reduced the risk of oral cavity cancer and other head and neck cancers. Vitamin E from dietary sources may also play a protective role. The key appears to be the whole-food source rather than supplements, since fruits and vegetables deliver a combination of antioxidants, fiber, and other compounds that work together to protect cells from damage.
Scientists estimate that most cases of mouth, throat, and larynx cancer in Western countries could be prevented through three straightforward measures: not smoking, limiting alcohol, and eating a diet rich in fruits and vegetables. Despite this, most people in many developed countries fall short of the recommended daily intake of produce.
Genetic Conditions
A small number of inherited conditions raise throat cancer risk substantially. Fanconi anemia, a rare genetic disorder that impairs the body’s ability to repair damaged DNA, carries an especially high risk. People with Fanconi anemia develop cancers at young ages, and the most common type is squamous cell carcinoma of the head and neck, particularly affecting the tongue and the lining of the mouth, followed by the esophagus. Because their DNA repair mechanisms are compromised, cells in the throat and mouth are more vulnerable to the mutations that lead to cancer.
Other inherited immune deficiencies and conditions that suppress the immune system (including organ transplant medications) can also raise susceptibility, since the immune system plays a critical role in detecting and eliminating abnormal cells before they become cancerous.