Why is the average lifespan of men significantly shorter than that of women? Heavy physical labor, engagement in dangerous jobs, and later retirement are the main reasons for men's shorter lifespan! By 2025, the gap in average life expectancy between Chinese men and women will reach an astonishing ten years (the actual official average life expectancy is 79.25 years, with the gender gap usually around 5-7 years, but some mortality age statistics show the median difference is even larger), whereas the global average difference is five years.