“Because each organ has its own pool of stem cells to replenish aged tissue, scientists have long thought that the body has multiple “aging clocks” running concurrently.

As it turns out, that’s not quite right.

This week, a study published in Nature threw a wrench into the classical theory of aging. In a technical tour-de-force, a team led by Dr. Dongsheng Cai from the Albert Einstein College of Medicine pinpointed a critical source of aging to a small group of stem cells within the hypothalamus—an “ancient” brain region that controls bodily functions such as temperature and appetite."