An analysis of adolescents and young adults between 1973 and 2015 resulted in 497,452 cancer patients in the United States between 15 and 39 years old. Diagnoses increased from 57 to 74 per 100,000 young adults. For males, the most common cancers were similar to adults, with testicular, melanoma, and non-Hodgkin lymphoma while females were breast, thyroid, cervical, and uterine cancers. But earlier diagnoses led to detecting kidney, thyroid, and gastrointestinal cancers as well. While obesity and smoking are clear risk factors for cancer, we often get a muddy picture of environmental causes, with epidemiologists writing weekly papers statistically correlating to cancer to nearly any food or chemical.