Hunza skin color contains melanin to protect from harmful UV.
High mountain ranges reduce long hours of direct UV sun exposure.
Hand cultivated crops with none chemical exposure increases longevity.
The life expectancy of the average Westerner is about 70 years. The life expectancy of the average Hunza falls onto a different scale altogether - these people reach both physical and intellectual maturity at the venerable age of one hundred.
According to a number of sources, it is not uncommon for 90 year old Hunza men to father children. Hunza women of 80 or more look no older than a western woman of 40