Increase of the Human Life Span If the average life span were increased to 150 years, what major changes in society would you expect? Discuss. The average life span of people in this day and age is anywhere from seventy-five to ninety-five years. If this were dramatically increased to one hundred and fifty years, there would be major changes in society as we know it. One of these changes would be overpopulation. There would be an increased awareness of personal health. Lastly, we would find that instead of the retirement age being around sixty-five, it would probably skyrocket to around one hundred and twenty. Such a dramatic change in life span would have several major reactions