A risk factor is anything that affects a person’s chance of getting a disease such as cancer. Different cancers have different risk factors.
Lifestyle-related risk factors such as tobacco use, diet, body weight, and physical activity play a major role in many adult cancers. But these factors usually take many years to influence cancer risk, and they are not thought to play much of a role in childhood cancers, including leukemias.
There are a few known risk factors for childhood leukemia.