|MadSci Network: Anatomy|
Since no actual measurements of this number are available, we must resort to estimates. The estimates I found are in the range that you reported (60,000 to 100,000 miles). One reference stated that 60,000 miles was for a child (but didn't say what age), while 100,000 miles would be more accurate for an average adult. The medical textbooks that I reviewed are silent on this subject.
I should mention that this issue was discussed on the Mad Scientist forum in 1999 as well! That question and response can be found at reference #1 below.
Thanks for your question! Sorry I couldn't be more precise.
Stephen C. Lattanzi, M.D.
1. http://www.madsci.org/posts/archives/jan99/916069852.An.r.h tml
2. http://www.medicinenet.com/script/main/art.asp? articlekey=194
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