Japanese researchers studied why women live longer than men by comparing age-related changes in their immune systems. The scientists found out that women tend to have an immune system which ages slower than men’s. The study was made by analyzing blood serum and blood cells of healthy volunteers in Japan, aged between 20 and 90 years old.
Regardless of the gender, as one person ages, its number of white blood cells decrease and the body cannot fight efficiently against infections. Antibodies, which attach to potentially harmful foreign bodies circulating in the bloodstream, marking them for other cells to attack, are produced in a smaller quantity too.
But as they age, women tend to maintain better immunological parameters than men.
“The process of aging is different for men and women for many reasons,” explained Katsuiku Hirokawa from the Tokyo Medical & Dental University Open Laboratory, according to the international press. “Women have more estrogen than men which seems to protect them from cardiovascular disease until menopause. Sex hormones also affect the immune system, especially certain types of lymphocytes.”
In Japan life expectancy for men is 79 years while women are expected to reach 86 years, the World Health Organization reports. Globally women live, on average, six to eight years longer than men.