According to the Centers for Disease Control and Prevention (CDC), women on average live anywhere from 5 to 7 years longer than men. There are several key factors that influence the life expectancy differences between men and women. Men and boys are more likely to be involved in risky and violent behavior than women and girls. More men die from suicide, murder, car accidents, and cardiovascular related diseases than do women. The major factor however, that influences life expectancy is genetic make-up. Women typically live longer than men because of their genes.
Scientists believe that the key to why women live longer than men is gene mutation. DNA mutations in the mitochondria of men account largely for the differences in life expectancy between men and women. Mitochondria are cell organelles that provide the energy needed for cellular function. With the exception of red blood cells, all cells have mitochondria. Mitochondria have their own DNA, ribosomes, and can make their own proteins.
Mutations in mitochondrial DNA were found to increase the rate at which males age, thus lowering their life expectancy. These same mutations in females however, do not influence aging. During sexual reproduction, the resultant offspring receive genes from both the father and mother. Mitochondrial DNA however, is only passed on via the mother. Mutations that occur in female mitochondria are monitored through genetic variation so that only favorable genes are passed from one generation to the next. Mutations that occur in male mitochondrial genes are not monitored so the mutations accumulate over time. This causes males to age faster than females.