What metaphorical means

We age because our bodies forget how to be young - David A. Sinclair
At its core, this quote means aging isn't passive decay. It's an active biological process where our cells lose the epigenetic information, the "software", that tells them how to function in a youthful, healthy state.
Aging is not the opposite of youth It Meaning Factcheck Usage

Quotes about metaphorical

Aging is not the opposite of youth. It’s the loss of information - David A. Sinclair
The core idea here is that aging isn't a separate state from youth, but rather the gradual decay of the biological information that keeps our bodies young and functioning properly.