One in three of the seven million cancer death worldwide is caused by nine potentially modifiable risk factors, according to a study from Harvard Medical School (Lancet, November 19, 2005.) Being overweight causes your full fat cells to release chemicals that cause inflammation that can lead to cancer. Lack of exercise increases inflammation that causes cancer by the same mechanism as full fat cells.

Lack of fruit and vegetables deprives you of antioxidants that prevent cancer. Phytochemicals are substances found in plants that have been identified by researchers as beneficial to humans. We have identified only a few of the thousands of phytochemicals, and we do not fully understand how they work, but many have been linked to cancer prevention, such as capsaicin in peppers, lycopene in tomatoes, sulforophe in the cabbage family, allicin in onions and garlic, and genistein in soybeans.

Smoking exposes you to nicotine that causes blood vessels to grow and nourish cancer cells. Excess alcohol dehydrates cells, which can cause cancer. Unprotected sex exposes you to cancer-causing viruses. Urban air pollution and indoor smoke from solid fuels expose you to carcinogens in the air, and contaminated injections expose you to viruses and other agents that cause cancer. Excessive sun exposure or sunburns increase skin cancer risk.

You can improve your odds against cancer by avoiding overweight, eating a wide variety of fruits and vegetables, exercising, avoiding smoking and alcohol, practicing safe sex, and avoiding indoor and outdoor air pollution whenever possible. Avoid injections unless they are necessary for health.

Gabe Mirkin, M.D.

Dr. Gabe Mirkin has been a radio talk show host for 25 years and practicing physician for more than 40 years; he is board certified in Sports Medicine and three other specialties.

Dr. Mirkin's daily features on fitness have been heard on CBS Radio News stations since the 1970's. He has written 16 books including The Sportsmedicine Book, the best-selling book on the subject that has been translated into many languages. His latest book is The Healthy Heart Miracle, published by HarperCollins.

Dr. Mirkin is a graduate of Harvard University and Baylor University College of Medicine. A Boston native, Dr. Mirkin did his residency at the Massachusetts General Hospital. He has served as a Teaching Fellow at Johns Hopkins Medical School, Assistant Professor at the University of Maryland, and Associate Clinical Professor in Pediatrics at the Georgetown University School of Medicine. He has run more than forty marathons and is now a serious tandem bicycle rider with his wife, nutritionist Diana Mirkin.