Before I jumped into a writing career that opened my eyes to the consequences and causes of cancer, I lived a couple of decades of my life under the assumption that cancer was something we had little control over.

Of course, now I know that a person’s lifestyle can impact how high or low their cancer odds are stacked — even when there’s a genetic risk factor

But when assessing those risks, we’re learning more about the role bacteria play. For example:

• Most cases of stomach cancer are caused by bacteria.
• A majority of cervical cancers, as well as some genital and oral cancers, are caused by a virus.
• Certain chronic viral infections can lead to liver cancer.

4 Cancer-causing infections

According to the American Association for Cancer Research, cancer-causing infections account for about 13 percent of all cancer cases worldwide.

Here’s what you need to know about four potential cancer-causing infections — and how to beat them back…

Infection #1: Human papillomavirus (HPV)

Of the 200 or so types of HPV, a dozen significantly increase the risk of cervical, genital and oral cancers.

HPV usually goes away on its own. However about ten percent of women with HPV in the cervix will go on to develop a persistent infection. This can cause cells to replicate rapidly. At the same time, it deactivates proteins that suppress tumors.

Most sexually active people will be infected with human papillomavirus at least once in their lives. Using condoms cuts the risk, but vaccination offers the strongest protection. Some research has shown that high levels of specific antioxidants may help prevent the onset of cancer-causing HPV.

The CDC recommends two or three doses of the HPV vaccine starting around age 11 or 12 and through age 26. But older adults can benefit from being vaccinated if they weren’t when they were children.

Also, a yearly Pap smear can save your life. Your doctor can look for abnormalities caused by HPV before they turn into cancer.

Infection #2 and #3: Hepatitis B and C

These viruses lead to cancer by causing inflammation in liver cells. Chronic inflammation leads to scar tissue and cirrhosis, a strong risk factor for liver cancer.

Hepatitis B and C are both spread through contact with infected blood, semen, and other bodily fluids. In practical terms, that means it’s spread through unprotected sex and by sharing infected needles.

There is a highly effective vaccine against Hep B. Having diabetes or living with someone who has Hep B are two major risk factors. Adults with these and other risk factors should be screened and receive the vaccine if they haven’t as a child (infant vaccination for Hep B has been recommended since 1991).

There’s no vaccine for Hep C, but antiviral medications can cure it. But you can go years without even knowing you have the infection.

Infection #4: H. pylori

H. pylori is a very common infection. About three percent of people with H. pylori will develop cancer. Scientists still aren’t sure why this happens.

Bacteria are found in saliva and the plaque on our teeth. This means that the best way to prevent an H. pylori infection is to avoid sharing food utensils, drinking glasses and toothbrushes.

The bacteria is also found in feces. Washing hands well with soap and water for at least 20 seconds before preparing food or eating, as well as after using the bathroom, will kill it.

H. pylori is mainly associated with gastric (stomach) cancer. If you have stomach ulcers, stomach pain or bloody stools, ask your doctor about being tested for the bacteria.

The risk of gastric cancer in people who carry H. pylori bacterium is around 14 percent. But a breakthrough study found that in patients who had both H. pylori, plus one of five genetic variants, the risk of gastric cancer in their lifetime jumped to 45 percent.

Prevention is key, even when genetics are involved

The good news here is that we have weapons at our disposal to greatly reduce our risks for many types of cancer.

Some powerful examples are what’s known as chemopreventive foods and exercise…

A team of scientists from The University of Texas MD Anderson Cancer Center described exercise’s impact on cancer as “mind-blowing,” when pitted against a genetic cancer predisposition known as Lynch Syndrome (LS) — which impacts more than a million Americans.

They saw high-intensity interval training (HIIT) increase cancer-fighting cells, improve the immune system’s ability to detect and remove potential cancer cells and make significant changes to gene expression.

That means, no matter what potential avenue cancer could take to affect your health — take control.

Sources:

These Four Common Infections Can Cause Cancer — NY Times

About the AACR Cancer Progress Report — American Association for Cancer Research