Cancer is a chronic disease characterised by the uncontrollable and abnormal division of cells in a part or in parts of the body. Cancerous cells can move throughout the body through the blood or the lymphatic systems and hence capable of destroying healthy tissues in a process known as invasion. It is the second most cause of deaths worldwide. We shall discuss some of the cancer causes and prevention below. There are said to be over two hundred forms of cancer; anal cancer, bladder cancer, bone cancer, breast cancer, cervical cancer, colon cancer, and colorectal cancer just to mention a few. Scientists claim and attribute the causes of cancer as prolonged and excessive alcohol intake, smoking of tobacco, unhealthy lifestyles, ultraviolet ray exposure from the sun, poor dieting and poor medical care. The risk of being diagnosed as having cancer can significantly be reduced by avoiding tobacco, restricting or limiting alcohol intake, reducing exposure to ultraviolet rays from the sun through application of sunscreens and working in shades, tanning beds, ensuring and maintaining a healthy diet, level, seeking regular medical care and ensuring fitness through exercising. In addition, far from the mentioned cancer causes and prevention, there are also environmental causes of cancer in children such as natural radioactivity from volcanic activities, radiation and genetics.