A World-Wide and Time-Honored Custom
Everywhere in the world, and through all time, women outlive men. In every country characterized by advanced social and industrial conditions or in countries of early culture, this fact is strikingly constant. It has in the past been accounted for chiefly by the difference of habits, men smoking more, drinking more, adopting additional risks, and, therefore, a higher risk of mortality, but the persistence of this condition in the countries where painting was more equalized in the matter of habits suggests that something more than habits is concerned.
The fact is now apparent that investigators are looking for the cause of longevity in a genetic respect.
The X Factor in X Chromosomes
Every woman has a double X, while the man has an X and a Y. This gives to women a distinct biological advantage in that no one can say what is the ultimate cause, with these factors in life. The X chromosomes contain hundreds of genes, some of them absolutely essential in cell rehabilitation and in immunity of disease.
The existence of an X allied chromosome makes it impossible for one X to possess a harmful genetic factor, so that autochthonous restoration to normalcy eliminates the defects, which do not exist in the members of the race. The Y chromosome is smaller, all in all, and in it there are very, very few genes which can be helpful in maintaining an organism through the processes of time and degeneration. Thus in time the genetic imbalance of men’s chromosomes to a genetically effectually remove them more susceptible to certain diseases and degeneration due to age.
Beyond Biology:
A Complex Equation Reported in the Oct. 5 New England Journal of Medicine, a study at the University of California at San Diego suggests that there is more than just that structure of the chromosome that accounts for greater female longevity. Social, environmental and hormonal influences may count, too.
For example, estrogen, the female hormone, is believed to protect the heart and improve the immune function; testosterone may induce riskier behavior and augment stress levels. The life expectancy itself is affected by changes in lifestyle, availability of health care and hazards of employment, etc. Yet the constant feminine advantages in life spans over centuries and in disparate nations show an evolutionary resiliency in their female biology.
The Mystery Continues
Not only are scientists still in the dark about what genes on the X or Y chromosome influence longevity in any way, but they are also not sure which genes these are, notwithstanding the great strides being made in genetics today. But researchers are at work trudging through molecular avenues to solve the question of what causes the difference in longevity between the sexes. Perhaps someday research will disclose new factors in the process of aging that will be beneficial to all humanity. What comes to light, however, is that the circumstances of the two X chromosomes in the female may be more than a representation of being of the female sex. It may be nature’s positive insurance policy against premature demise and adverse health conditions.
