Fascinating new information about how and why we age casts fresh light on the long lifespans of pre-Flood people. In the book of Genesis, the Bible routinely records human lifespans which seem outrageously different from our experience today. Notice the pronounced drop in lifetimes following the Flood. This is evidence for something very dramatic happening in world history. These great ages are not presented in the Bible as if they are in any way extraordinary for their times, let alone miraculous.
Many people are quick to scoff at such ages, claiming they are 'biologically impossible'.
Today, even if they avoid all fatal diseases, humans will generally die of old age before they reach much past 100. Even the very exceptional cases don't make it much past 120 years. However, a look at the evidence related to aging suggests that the apparent upper limit on today's average lifespans is not something that is 'biologically inevitable' as such for humans or other multi-celled creatures. Disease, diet, 'wear and tear' and other environmental factors undoubtedly play a part in how long we live. However, it now appears that underlying all these are factors somehow written into our genetic code, which determine what our 'upper limit' is.