alpha hydroxy acid question again

[KRISTA UNDERHILL]

Good morning,
If you only remove parts of the stratum corneum as you suggested would probably not disturb the dermal fibroblasts, would collagen production also not be stimulated, which is one of the benefits of aha use? Or is this related? Is it the aha or the resulting inflammation that causes fibroblast proliferation? I so much appreciate you sharing your knowledge. Thank you, Krista.

[drtodorov]

Good question. Unfortunately, I do not have a definitive answer. AHA seem to have a dual mechanism of action - via exfoliation, and directly as chemical signals. It is not quite clear how much each part contributed to increased collagen synthesis in vivo.

It is true that causing limited skin trauma is a popular and legitimate may to boost collgen synthesis (which is a part of the would-healing and resulting skin remodelling). When done occasionally and in a controlled way, the benefits often outweigh the risk. However, if you exfoliate, say, every othe day to the dergree that your skin is constantly irritating and a perpetual healing mode, you may see wrinkle improvement for a year or two, but in the long-run you are likely to end up with more aged skin.

Anyway, there are other ways to boost collagen (e.g. boost synthesis with vitamin C and its derivatives, or reduce breakdown with retinoids).

[KRISTA UNDERHILL]

Thank you doctor. Does vitamin c, it's derivatives, or retinoids cause fibroblast proliferation?

[drtodorov]

It you overuse C or retin A and cause skin irritation, yes. But if you are careful - then no.

[KRISTA UNDERHILL]

Dr., What would you consider overuse of these ingredients? Is it figured as a percentage or how often it is used? In your opinion what would be considered within safe limits?

[drtodorov]

Generally, any signs of irritation, or increase in skin dryness of sensitivity means overuse.