(Nature) – Research is revealing the cellular mechanisms that link mental well-being and longevity.

There might be a paradox in the biology of ageing. As humans grow older, their metabolisms tend to slow, they lose muscle mass and they burn many fewer calories. But certain cells in older people appear to do the exact opposite — they consume more energy than when they were young.

These potential energy hogs are senescent cells, older cells that have stopped dividing and no longer perform the essential functions that they used to. Because they seem idle, biologists had assumed that zombie-like senescent cells use less energy than their younger, actively replicating counterparts, says Martin Picard, a psychobiologist at Columbia University in New York City. (Read More)