Women With Fewer Children Live Longer: Study
Most women live longer than men due to birth rates, says a study conducted by Utah Population Database from Uppsala University. Using the demographic record of 140,600 individuals, the study has been recorded in the Scientific Reports.
Surprisingly, those men who had been born in the early to mid-1800s lived two years more than women. But over time, women born in the early 1900s lived longer by four years, Science Daily reported.
As the birth rates had come down by 8.5 percent in the early 1800s to 4.2 percent children per woman in the early 1900s, they showed a corresponding rise in the female lifespan even as the lifespan of men was steady.
Hence, the differential costs of reproduction showed shifting patterns of sex differences and lifespans through various populations.
The information that had been collected also showed that women who mothered 15 children or more tended to live six years less than mothers of single children. However, the lifespans of men never got affected by the number of children they fathered.
The life-history theory revealed that every person has few resources that could help to enhance reproduction or repair the body. Hence, even as women pay the higher costs of reproduction than men, their low birth rates also help the female lifespan, First Post reported.
Biological factors can also be factored while understanding the reasons behind the shift in mortality patterns. As more countries undergo a demographic transformation, the overall sex differences in lifespan may also go up.
