Signalling, not irritation
Cosmetic actives tend to work on skin in one of two ways. Some signal: they present cells with a molecule from the same family the tissue already uses to coordinate itself. Others irritate, on purpose and at a low level, provoking a stress response that speeds the skin up.
Growth factors are signalling proteins by definition. That is the class they belong to.
We make no claim about what happens on your scalp. The program cites one independent study of the FGF·2 active, Note 09, and reports what it measured. In that study no serious adverse events were reported; 1 in 10 people in the active group said their hair felt slightly heavy after applying it. As with anything you put on skin, stop if you notice irritation.
What is the difference between signalling and irritation as modes of action?
A definition from the cosmetic literature: signalling presents a cell with a molecule from a family the tissue already uses; controlled irritation provokes a stress response that speeds turnover. Growth factors are, by definition, signalling proteins. OF·27 makes no claim about what its formula does in the scalp.
Were adverse events reported in the study of the active?
No serious adverse events were reported; 10% of the active arm reported hair feeling slightly heavy after application. Stop use if irritation occurs.
The notes, by email.
One note at a time, in reading order, and a message when a new one is published.
An independent hair-science program.
The protocol the notes describe: The OF·27 Protocol
OF·27 is marketed as a cosmetic and is not intended to diagnose, treat, cure or prevent any disease.