evidence: Maintaining a healthy weight might lower the risk of various types of cancer, including cancer of the breast, prostate, lung, colon and kidney. Being overweight causes the body to make and circulate more estrogen and insulin, hormones that can stimulate cancer growth. One of the best ways to get an idea if you are at a healthy weight is to check your body mass index, a score based on the relationship between your height and weight. Most people are at normal weight if their BMI is below 25. Be physically active. Approximately 3% of cancer cases are attributed to physical inactivity. Being physically active might lower the risk of breast cancer and colon cancer. Exercise fights obesity and lowers levels of hormones like estrogen and insulin, which have been linked to cancer. Get immunized (HPV & Hepatitis vaccines). Certain viruses have been linked to cancer, but are preventable through vaccination. In the U.S., approximately one-third of liver cancers are linked to the hepatitis B virus and hepatitis C virus. The hepatitis B vaccine can help lower liver cancer risk. Talk to your physician about age recommendations for the human papillomavirus vaccine. The HPV vaccine helps prevent most cervical cancers and several other kinds of cancer. Get regular screenings. Getting screening tests regularly may find breast, cervical, and colon cancers early, when treatment is likely to work best. For more information on to how prevent cancer, visit USAFwellness.com or contact your local Civilian Health Promotion Services team. Comprehensive information on cancer prevention can be found at the Centers for Disease Control and Prevention website at cdc.gov.