Cancer prevention is defined as an active measure to decrease the incidence of cancer. This can be done by avoiding alcohol, smoking, physical inactivity and being overweight. Epidemiologic evidence describes that avoiding excessive alcohol consumption may contribute to reductions in risk of certain cancers. However, compared with tobacco exposure, the magnitude of effect is modest or small and strength of evidence is often weaker.

Other lifestyle and environmental factors known to affect cancer risk include certain sexually transmitted diseases, the use of exogenous hormones, exposure to ionizing radiation and ultraviolet radiation, and certain occupational and chemical exposures. Every year, at least 200,000 people die world wide through cancer.

To reduce the risk of developing cancer, not only cancer the risk of other chronic diseases might also be prevented by low fat, healthy diet and healthy lifestyle. There is also evidence that total fat intake of greater than 30 percent of total calories can increases the risk of developing some cancers. Experts says, we can reduce their risk of developing cancer by 35 percent if they eat a healthy diet, not smoking, being active and eating complex carbohydrates, not drinking alcohol, limiting red meat, limiting salt. Prevention of cancer is always better than spending lots for its curing.