Body change?

If our entire body is supposed to renew itself every 7 years, if all our blood renews itself every three to four months, and if even our skin renews itself every 28 days, how come I wind up with exactly the same spots, wrinkles, scars and bumps every time?
According to a book by Larry Dossey called Space, Time & Medicine, the body only takes 5 years to renew completely. He says somebody called Aebersold has concluded that 98% of the our 10 to the power of 28 atoms are renewed annually. The same source says the lining of the stomach is replaced every week (so much for cast-iron stomachs); the liver is regenerated every six weeks.
Hmmm. Does this mean that the DNA coding actually changes in accordance with the bumps and bruises we receive through life and keeps track of them? How odd.
Another source claims men take a year longer than women to completely change. I wonder why?
My suspicion is that there may be an element of truth in this body change business, but it’s hard to find a medical fact about it. Most sites that talk about it are promoting beauty products, rather than medical information. Have to keep digging on this one, I think.