Why isnt stomach or colon cancer chances high in.my 20s? explain.in detail please

It is a good thing: It's good that the risk to develop colon, stomach or other type of cancer in our 20's , in general , is not high. Unless if you have a strong family history of colon ca such as in familial adenomatous polyposis or stomach cancer, then the risk would be much higher. That is because when we are younger, the gene repair mechanism is still functioning well and exposure to carcinogenic is still limited.

Takes time to develo: Colon cancer in your 20's can happen and does, but it is very unusual. It takes time to develop unless there is a genetic predisposition or your lifestyle contributes to earlier than usual development of either cancer. If in doubt see you doctor.