Cancer

Cancers are primarily an environmental disease with 90-95% of cases due environmental factors such as lifestyle, and 5-10% directly due to heredity. Common environmental factors leading to cancer include: tobacco (25-30%), diet and obesity (30-35%), infections (15-20%), radiation, lack of physical activity, and environmental pollutants. These environmental factors cause or enhance abnormalities in the genetic material of cells. Cell reproduction is an extremely complex process, which is normally tightly regulated by several classes of genes including oncogenes and tumor suppressor genes. Hereditary or acquired abnormalities in these regulatory genes can lead to uncontrolled cell growth, and the development of cancer