White coated Lamb
A person's life expectancy is an important indicator of the health status based on the average number of years a person may be expected to live at a given age in consideration with the current mortality rates.
Study shows that females live longer than males. According to the latest figures released by the CDC, the average American man lives up to age 76 while the average woman in America lives up to 81 years. Note that the woman's extra years tend to be healthy ones.
American men can look forward to 67 healthy years, while American women enjoy 70 years living a healthy life, according to the World Health Organization's HALE index, which computes how long a man or a woman can expect to live without having a major disease or injury.
This supports the results of a recent study on mammals that shows females live substantially longer than males. On average, females live up to 18.6% longer than males from the same species.
Animals vs. Humans
The study conducted by the researchers from the University of Southern Denmark and University Lyon 1 in collaboration with several international teams, came up with the results that although women live longer than men, they are still outlived by their female mammal animal counterparts.
A wild mammal lives 18.6% longer than males of the same kind, while the difference between a man and woman's life expectancy is only 7.8%. Their findings were published in the Proceedings of the National Academy of Sciences of the United States (PNAS).
Associate professor and an expert in biostatistics at Interdisciplinary Centre on Population Dynamics, University of Southern Denmark, Fernando Colchero, identified animals such as the lion, killer whale, brushtail possum, moose, greater kudu, and sheep as the best examples of non-human mammals that shows great differences on life expectancy.
Over 130 wild mammal populations were analyzed by the researchers and they were able to estimate the average longevity and rate of increase in the risk of dying because of the age for both sexes of the animal. Their analyses led to an unexpected result that a vast majority of cases exceeds the difference observed between non-human mammals to the human populations.
Why do females live longer than males?
Experts say that the male-female lifespan gap is not a new phenomenon and it is not only restricted to Americans. It is true to all societies, and even true for the great apes, according to a professor of neuropsychiatry at the University of New South Wales, Dr. Perminder Sachdev who studied human longevity.
Sachdev explained that the reason why women tend to live longer than men is because of biology and behavior.
Unlike women, men are more likely to indulge in a sedentary lifestyle like smoking, excessive drinking, and be overweight. Additionally, men are also less likely to seek medical help early once they are diagnosed with a disease, and are also more likely to be non-adherent to treatment.
To top it all off, men are more likely to engage in risky activities that are life-threatening such as brawls or gunfights making them more susceptible to dying earlier than women.
Another explanation could also be because of a man's biology. Males produce more androgens, a male hormone that modulates immune performance. When it is present at high levels, androgens can impair some of the aspects of the immune defense that results in men more likely to be infected with diseases.
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