People fasted all the time in days of yore. Some for religious reasons and some had little choice.
Average lifespan: 40-45.
Very weak point. High infant and child mortality lowered the past’s average lifespan dramatically.
Today about 13% of pregnancies end in abortion. That’s about 1 out of 7. If you included the deaths of those people, today’s average life expectancy would be reduced around 13%.