Why Women Live Longer Than Men
It's all about the mitochondria, those cellular power plants that convert food to energy. A team of scientists in the UK found numerous mutations within mitochondrial DNA that affect how quickly males show their age and how long they eventually live. "Intriguingly, these same mutations have no effects on patterns of aging in females," lead researcher Dr. Damien Dowling said, according to a university release.
Dr. Dowling went on to say that all animals possess mitochondria and that the tendency for females to outlive males is common to many different species. "Our results therefore suggest that the mitochondrial mutations we have uncovered will generally cause faster male aging across the animal kingdom,” he concluded.
The team pointed out that these mutations can be attributed to the way the mitochondrial genes are passed down from parents to offspring. “While children receive copies of most of their genes from both their mothers and fathers, they only receive mitochondrial genes from their mothers," Dr. Dowling said. "This means that evolution’s quality control process, known as natural selection, only screens the quality of mitochondrial genes in mothers. If a mitochondrial mutation occurs that harms fathers, but has no effect on mothers, this mutation will slip through the gaze of natural selection, unnoticed. Over thousands of generations, many such mutations have accumulated that harm only males, while leaving females unscathed.