Human Cells Divide 50 Times?

Most of your cells don't divide every day. Many of your cells will last for years. Differing cell lines will have differing limits. Check the link, the subject you're interested in is "Hayflick limit."

The Hayflick limit doesn't apply to stem cells and non-differentiated cells. In humans the Hayflick limit is 52. But certain cells are excluded. Cancer cells also do not follow this limit but mostly because the have activated telomerase enzymes that repair telomere degeneration seen as the cause of the Hayflick limit.

Well, whether or not human cells die after 50 divisions is true or not, there is a simple reason why we don't die at the end of a cell's life cycle. Each of the baby cells also starts to divide and the generations after take the place of the ones before.

Where did you get they divide 50 times and die?

After they divide the daughter cells start all over.

Not all human cells are alike, and do not divide at the same rate.

After differentiation, some can divide thousands of times and some never do.