Stomach Cancer: Risk Factors

What is a risk factor?

A risk factor is anything that may increase your chance of having a disease. Risk factors for a certain type of cancer might include smoking, diet, family history, or many other things. The exact cause of someone’s cancer may not be known. But risk factors can make it more likely for a person to have cancer.

Things you should know about risk factors for cancer:

• Risk factors can increase a person's risk, but they do not necessarily cause the disease.

• Some people with 1 or more risk factors never develop cancer. Other people can develop cancer and have no risk factors.

• Some risk factors are very well known. But there is ongoing research about risk factors for many types of cancer.

Some risk factors, such as family history, may not be in your control. But others may be things you can change. Knowing the risk factors can help you make choices that might lower your risk. For example, if an unhealthy diet is a risk factor, you may choose to eat healthy foods. If excess weight is a risk factor, your healthcare provider may check your weight or help you lose weight.

Who is at risk for stomach cancer?

Risk factors for stomach cancer include:

• Age. Most people with stomach cancer are in their late 60s or older.

• Sex. Stomach cancer is more common in men.

• Race. In the United States, stomach cancer is more common in Hispanics, African Americans, Asians, and Pacific Islanders.

• Blood type. For unknown reasons, people with the blood type A have a higher risk.

• Diet. People who eat a lot of smoked, salted, pickled, and cured foods are at higher risk.

• Smoking. Smoking increases the risk for stomach cancer.

• Alcohol. Heavy alcohol use may increase your risk.

• Overweight and obesity. Being overweight or obese may increase the risk for stomach cancer in men.

• Helicobacter pylori (H. pylori) infection. H. pylori is a bacterium that causes many cases of stomach ulcers. Long-term infection with H. pylori is also a major risk factor for stomach cancer.

• Previous stomach surgery. Having part of your stomach removed for reasons other than cancer increases the risk for stomach cancer. Problems with reflux after surgery may also add to the risk.

• Pernicious anemia. People with this condition are not able to absorb vitamin B12. This causes them to have low red blood cell levels (anemia) and other problems. This type of anemia also puts a person at an increased risk for stomach cancer.

• Stomach polyps. A polyp (adenoma) is a type of growth that can occur in the stomach. Having these raises your risk for stomach cancer.

• Long-term inflammation. People with chronic or long-term inflammation of the stomach lining (gastritis) are at higher risk for stomach cancer.

• Common variable immune deficiency (CVID). People with CVID have frequent infections. This is because their immune system doesn’t work the way it should to fight germs. They also tend to have other problems. These include gastritis and pernicious anemia. This puts them at an increased risk for stomach cancer.

• A toxic workplace. People who work in the coal, metal, and rubber industries are at increased risk. This may be because of toxic dust and fumes that are inhaled.

• Having family members with certain conditions. Some of the issues include:

  • Stomach cancer in parents, brothers, sisters, or children

  • Hereditary nonpolyposis colorectal cancer or Lynch syndrome

  • Familial adenomatous polyposis

  • Breast cancer gene mutations BRCA1 and BRCA2

  • Li-Fraumeni syndrome

  • Peutz-Jeghers syndrome

What are your risk factors?

Talk with your healthcare provider about your risk factors for stomach cancer and what you can do about them.