While experts cannot say how many years it may take to develop mouth cancer from smoking, they do know it is a leading risk factor for the condition, with most cases occurring in people who smoke.

Organizations such as the American Cancer Society (ACS) point to smoking and tobacco use in general as leading risk factors for developing mouth cancer, which doctors may also call oral cancer.

This article reviews different types of mouth cancer, risk factors, how quitting smoking affects a person’s risk, and more.

A note about sex and gender

Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Click here to learn more.

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According to the ACS, in 2023, an estimated 54,540 people will receive a new oral cancer diagnosis, and about 11,000 people will die from the condition.

Experts do not generally note how many cigarettes a person needs to smoke per day to increase their oral cancer risk. However, the ACS notes that long-term smoking or tobacco use increases risk.

The Mouth Cancer Foundation suggests that as many as 90% of oral cancer cases occur in people who smoke. It also states that smoking increases a person’s risk of oral cancer sixfold.

Locations of cancer

The majority of mouth cancer cases are squamous cell carcinoma, regardless of where the cancer starts. Squamous cells are flat, thin cells that appear in various parts of the body, including:

  • the surface of the skin
  • the lining of the digestive and respiratory tract
  • hollow organs

Locations in the mouth

Researchers note that tobacco use is a predominant risk factor for developing squamous cell carcinoma in the mouth, regardless of the starting location.

Oral cancer can develop in several different areas of the mouth, including:

  • gums
  • lips
  • the hard palette
  • the tongue
  • the inner cheeks

Some studies have looked at the locations of oral cancer in people who smoke and people who do not. The findings of one study from 2014 suggest people who do not smoke may have a higher prevalence of cancer at the edge of the tongue compared with people who do.

Smoking tobacco products through cigarettes, pipes, or cigars is a well-established, predominant risk factor for developing oral cancer.

However, other factors can also increase a person’s risk, including:

  • the use of chewing tobacco
  • excessive alcohol use
  • being male, as males are twice as likely as females to develop cancers of the mouth
  • being over the age of 55
  • certain inherited genetic mutations
  • the presence of certain types of human papillomavirus (HPV)
  • exposure to UV light, which is a particularly strong risk factor for lip cancer
  • issues with nutrition, such as a lack of vegetables and fruits in the diet

Quitting smoking can help reduce a person’s risk of developing oral cancer. People with a diagnosis of oral cancer can also decrease their risk of developing a recurrent case by quitting smoking or chewing tobacco use.

According to the National Cancer Institute, people who quit smoking cut their risk of developing cancer of the mouth or esophagus by 50% within 5 years.

Though they may not indicate the presence of cancer, a person may want to contact a doctor if they experience one or more of the following potential signs:

  • pain in the mouth
  • mouth ulcers that do not heal
  • red or white patches in the mouth or throat
  • speech issues
  • trouble swallowing
  • unexplained weight loss
  • a lump in the neck or mouth
  • thickening of the lip
  • trouble moving the jaw
  • loss of teeth with no clear reason
  • unusual bleeding or numbness in the mouth

Read more about possible signs of mouth cancer.

Treatment for mouth cancer can vary based on a person’s overall health and the cancer stage and location.

Some common treatments include:

Some risk factors for mouth cancer are out of a person’s control, such as genetic mutations, age, and sex.

However, a person may be able to reduce their risk of developing oral cancer by making lifestyle changes that can include:

  • quitting smoking and the use of chewing tobacco, if applicable
  • avoiding secondhand smoke
  • eating a balanced diet
  • limiting alcohol consumption

Although quitting smoking can be challenging, resources are available that may help. The Centers for Disease Control and Prevention (CDC) suggest:

  • trying nicotine replacement therapy, which can include over-the-counter patches and gums or prescription medications
  • group or individual counseling
  • calling 1-800-QUIT-NOW
  • trying the quitSTART app

Please can also find resources at Smokefree.gov, where they can sign up for a texting program that may help with quitting.

Read more about how to give up smoking.

Smoking increases a person’s risk of developing mouth cancer, with the risk increasing the longer a person smokes. Quitting smoking can lead to marked decreases in risk over time.

In addition, it is best to avoid chewing tobacco and drink only moderate amounts of alcohol to help reduce the risk of developing mouth cancer.

People can find several online supports that offer help with quitting smoking. They may also benefit from counseling or medications.