Cancer Prevention: Evidence-Based Strategies to Reduce Your Risk

Tobacco Cessation

Tobacco use is the single largest preventable cause of cancer. Smoking causes approximately 80–90% of lung cancer deaths and significantly increases the risk of bladder cancer, oesophageal cancer, kidney cancer, pancreatic cancer, stomach cancer, and liver cancer, among others. Smokeless tobacco and cigars also increase cancer risk.

Quitting at any age reduces cancer risk. Within 5 years of quitting, the risk of mouth, throat, oesophageal, and bladder cancers is cut in half. After 10–15 years, a former smoker’s lung cancer risk drops to about half that of a continuing smoker. Effective cessation tools include nicotine replacement therapy, prescription medications (varenicline, bupropion), counselling, and quit lines such as 1-800-QUIT-NOW.

HPV Vaccination

Human papillomavirus (HPV) is responsible for nearly all cervical cancers, as well as many cancers of the oropharynx (throat), anus, penis, vagina, and vulva. The HPV vaccine is one of the most effective cancer prevention tools available.

• Who should get vaccinated: The CDC recommends HPV vaccination for all children at ages 11–12, with catch-up vaccination through age 26. Adults ages 27–45 may discuss vaccination with their doctor.
• Effectiveness: The vaccine prevents infection with the HPV types that cause approximately 90% of HPV-related cancers.
• Safety: The HPV vaccine has been extensively studied and has an excellent safety profile, with over 135 million doses administered in the United States since 2006.

Even vaccinated individuals should still follow cervical cancer screening guidelines, as the vaccine does not protect against all cancer-causing HPV types.

Sun Protection

Ultraviolet (UV) radiation from the sun and tanning beds is the primary cause of melanoma and other skin cancers. Skin cancer is the most common cancer in the United States, with over 5 million cases diagnosed each year.

• Sunscreen: Use broad-spectrum SPF 30 or higher on all exposed skin, and reapply every 2 hours (or after swimming or sweating)
• Protective clothing: Wear long sleeves, wide-brimmed hats, and UV-blocking sunglasses when outdoors
• Avoid peak sun: Seek shade between 10 a.m. and 4 p.m. when UV radiation is strongest
• No tanning beds: Indoor tanning increases melanoma risk by 75% when started before age 35. There is no such thing as a “safe” tan
• Check your skin: Perform monthly self-exams using the ABCDE rule (Asymmetry, Border, Colour, Diameter, Evolving) and see a dermatologist for any suspicious changes

Diet, Weight, and Cancer Risk

Excess body weight is linked to an increased risk of at least 13 types of cancer, including breast cancer (post-menopausal), colorectal cancer, uterine cancer, kidney cancer, pancreatic cancer, liver cancer, ovarian cancer, and oesophageal adenocarcinoma. Maintaining a healthy weight is one of the most impactful steps you can take to reduce cancer risk after not smoking.

Alcohol and Cancer

Alcohol is a known carcinogen. Even moderate drinking increases the risk of several cancers, including breast cancer, liver cancer, oesophageal cancer, colorectal cancer, and stomach cancer. The risk increases with the amount consumed — there is no “safe” threshold for cancer prevention.

• Women: Even one drink per day increases breast cancer risk by approximately 7–10%
• Men: Heavy drinking (3+ drinks per day) substantially increases the risk of liver, oesophageal, and colorectal cancers
• Combined risk: The combination of alcohol and tobacco multiplies the risk of mouth, throat, and oesophageal cancers far beyond either factor alone

The American Cancer Society recommends limiting alcohol to no more than 1 drink per day for women and 2 drinks per day for men — or ideally, not drinking at all.

Physical Activity

Regular physical activity reduces the risk of several cancers, including colon cancer, breast cancer, and uterine cancer. Exercise also helps maintain a healthy weight, which provides additional cancer risk reduction.

• Adults: Aim for at least 150–300 minutes of moderate-intensity activity (brisk walking, cycling) or 75–150 minutes of vigorous activity (running, swimming laps) per week
• Limit sedentary time: Prolonged sitting is associated with increased cancer risk independent of exercise levels. Take breaks to stand and move throughout the day
• Any activity counts: Even small amounts of physical activity provide health benefits. Start where you are and gradually increase

Screening as Prevention

Cancer screening is not just about early detection — for some cancers, it is genuine prevention. Colonoscopy can find and remove precancerous polyps before they develop into colon cancer. Pap tests and HPV testing can detect precancerous cervical changes that can be treated before they progress. Screening is most effective when done at the recommended intervals.

Talk to your doctor about which screenings are right for you based on your age, sex, family history, and risk factors. Our screening guidelines page provides detailed recommendations.

Environmental and Occupational Factors

Certain environmental and workplace exposures increase cancer risk. While these account for a smaller proportion of cancers than lifestyle factors, they are important to be aware of:

• Radon: A naturally occurring radioactive gas that seeps into homes from the ground. Radon is the second leading cause of lung cancer after smoking. Test your home with an inexpensive kit and install a mitigation system if levels are above 4 pCi/L.
• Asbestos: Exposure to asbestos fibres, primarily in older buildings and certain industrial settings, increases the risk of mesothelioma and lung cancer. If you work with or around asbestos, follow all safety protocols and wear proper protective equipment.
• Air pollution: Long-term exposure to outdoor air pollution, particularly fine particulate matter (PM2.5), is associated with increased lung cancer risk.
• Workplace chemicals: Certain chemicals including benzene, formaldehyde, and vinyl chloride are known carcinogens. Follow workplace safety regulations and use appropriate personal protective equipment.

Genetic Testing and Prophylactic Measures

Some people inherit genetic mutations that significantly increase their cancer risk. Identifying these mutations through genetic testing allows for proactive prevention and enhanced screening.

• BRCA1/BRCA2: Mutations in these genes dramatically increase the risk of breast cancer (up to 72% lifetime risk) and ovarian cancer (up to 44% for BRCA1). Carriers may consider enhanced screening, risk-reducing medications (chemoprevention), or prophylactic surgery.
• Lynch syndrome (HNPCC): Increases the risk of colorectal cancer, uterine cancer, ovarian cancer, and stomach cancer. Carriers should start colonoscopy screening at age 20–25 and undergo more frequent surveillance.
• Other syndromes: Li-Fraumeni syndrome, familial adenomatous polyposis (FAP), and other inherited conditions each carry elevated risk for specific cancers. Genetic counselling can help determine whether testing is appropriate for you.

Prevention Strategies by Cancer Type

The table below summarises the most impactful prevention strategies linked to specific cancer types covered on this site.

Taking Action

Cancer prevention is not about perfection — it is about reducing your overall risk through consistent, evidence-based choices. Even making one change, such as quitting smoking or increasing physical activity, can meaningfully lower your risk. Here is a practical starting point:

1. If you smoke, quit. This is the single most impactful cancer prevention step. Ask your doctor for help or call 1-800-QUIT-NOW.
2. Get screened. Follow the recommended screening guidelines for your age and risk factors.
3. Get vaccinated. Ensure you and your children are up to date on HPV and hepatitis B vaccines.
4. Move more. Aim for at least 150 minutes of moderate activity per week.
5. Eat well. Emphasise fruits, vegetables, and whole grains; limit processed and red meat.
6. Limit alcohol. The less you drink, the lower your risk.
7. Protect your skin. Use sunscreen, seek shade, and avoid tanning beds.
8. Know your family history. Discuss genetic testing with your doctor if cancer runs in your family.
9. Test your home for radon. An inexpensive test can identify a major lung cancer risk factor.

Last reviewed: March 2026. Prevention recommendations are based on guidelines from the American Cancer Society, World Health Organization, U.S. Preventive Services Task Force, and Centers for Disease Control and Prevention.