Steve Jobs cancer caused by overworked, radiation, diet or drugs?

It is impossible to know. It is well established, that lifestyle and environmental factors only contribute to a fraction of all cancers. A series of studies looking into this found, that only 43 % of cancers are attributable to such factors: http://www.nature.com/bjc/journal/v105/n2s/index.h...

You could say that most cancers are caused by being alive. The fraction of lifestyle/environmental related cancers is large enough to make recommendations such as not smoking, eating a healthy balanced diet, be careful with sun exposure etc. But following these recommendations will not guarantee anybody a life without cancer.

Working hard is not a risk factor for cancer. Jobs did not eat meat (he did eat fish) and he was known to eat a healthy diet. He did use drugs and smoked marijuana for years. Smoking cigarettes is a known risk factor for pancreatic cancer, but marijuana is generally not smoked as often as cigarettes. So it's hard to say whether smoking weed played a role or genetics played a role or whether something else was involved.

What precisely are "pc chemical compounds". My pc leaks no variety of chemical compounds. Do you rather understand how lots radiation it takes to deprave DNA and in turn form a neoplasm? there is extra desirable than one sort of radiation, that are you relating? that's beneficial to re-examine and then re-submit a sparkling question.

No one knows what causes cancer, but we do know weed does not.