What is cancer caused by?

The primary cause of cancer is mutations in genes that control the growth and division of cells. Cancer can be caused by a number of factors, including:

- Genetic mutations: These can be inherited or acquired during a person's lifetime. Some genetic mutations are linked to specific types of cancer, while others can increase a person's risk of developing any type of cancer.

- Environmental factors: These include exposure to certain chemicals, radiation, and infectious agents. Some examples of environmental factors that can contribute to cancer include tobacco smoke, asbestos, benzene, and certain viruses.

- Lifestyle factors: These include factors such as diet, physical activity, and alcohol consumption. For example, a diet high in processed meats, red meats, and sugary drinks has been linked to an increased risk of certain types of cancer, while regular physical activity has been linked to a decreased risk of cancer.

- Immune system dysfunction: In some cases, cancer can develop due to a weakened or malfunctioning immune system. For example, people with HIV/AIDS or those who have undergone organ transplantation are at an increased risk of developing certain types of cancer.

In most cases, cancer is caused by a combination of factors, rather than a single cause.