More from the article ...

... Researchers reviewed 136 publications on popular aesthetic treatments. They wanted to answer a simple question: Do these treatments just make skin look younger, or do they actually renew aging tissue?

The study, posted on Research Square, has not yet been peer-reviewed.

The publications covered common treatments including fillers, lasers, platelet-rich plasma (PRP), ultrasound, microneedling, and radiofrequency.

Rather than simply asking whether skin looked better after treatment, the researchers looked for evidence that its underlying structure and function had changed too.

They used a 22-point system designed to look beyond increases in collagen and assess whether studies investigated broader changes in the structure, function, and cells of aging skin. ...