I'm convinced that our bodies were built to last a lot longer, but we currently have very limited communication with our bodies' intelligence (which is sometimes called the "innate"). Currently, muscle testing is probably the most common and reliable way people communicate with this intelligence, but this is changing.
Our bodies are not currently operating at their full potentials when it comes to health and immunity. When we access this potential, diseases that used to outsmart our immune systems no longer pose a challenge, and aging slows or stops.
This is related to something I posted last night about why humans must relearn basic survival with every life.
And this Q&A touches on many relevant aspects:
YEP.